Ainz Ooal Gown

:"I will announce the goal for everyone to turn Ainz Ooal Gown into an eternal legend. If there are many heroes, then we will replace them all. Let the entire world know that Ainz Ooal Gown is the true hero!"
::— Ainz announcing his goals, setting all of Nazarick into motion.
Ainz Ooal Gown (アインズ・ウール・ゴウン), formerly known as Momonga (モモンガ), is the main protagonist of the Overlord series. He is the guildmaster of Ainz Ooal Gown, Overlord of the Great Tomb of Nazarick, and the creator of Pandora's Actor. He is regarded as the highest of the Almighty Forty-One Supreme Beings by the NPCs of Nazarick.
In the New World, he is the Sorcerer King of the Sorcerer Kingdom and the most powerful magic caster in the world. His other identity is famously known as "Momon," a dark warrior and leader of Darkness, an adamantite ranked adventurer group of that nation. He is an adamantite class adventurer and the strongest adventurer known in E-Rantel.
== Appearance ==
Ainz Ooal Gown has the appearance of an Overlord, an undead skeleton creature who is devoid of skin and flesh. He tends to mainly wear an elaborate, jet-black academic gown adorned with golden
and violet edges. When he has no clothes on, his whole body alone is purely made up of just his bones. He also has a dark red orb floating under his ribs that emanates a feeling of dread.
Furthermore, he has a type of tiny dark red glow radiating from inside his empty eye sockets. Sometimes, however, that glow can become largely intensified, leading it to elicit faint reddish flames flickering about in both his two eyes. Additionally, Ainz has a dark halo-like object glimmering right behind his head.
In his dark warrior persona as Momon, Ainz wears a fully jet-black body armor adorned with purple and golden markings. Not only that, but he also wears a red cape out of admiration for his friend Touch Me. He is even equipped with two large swords on his back while carrying them both behind him.
=== Audience Hall Attire ===
In the presence of the Holy Kingdom envoys, the Sorcerer King Ainz Ooal Gown wore a different vestment attire than his usual getup. The hem and sleeves were made of spotless white fabric, and they were lightly decorated with gold and purple. It was bound up at the waist with a sash. He wore gloves that were colored the same as his garments, fitted with metal plates that sparkled in all the colors of the rainbow.
== Personality ==
While Ainz is a cautious and stingy person, he will always try to plan ahead and control details beforehand in order to avoid any haphazard actions that can endanger Nazarick's existence. This means going so
far as lying to the inhabitants in the New World that he can't use one of his Super-tier spells for years to come after using it once. Since being transferred to the New World and becoming an actual undead
being, Ainz has felt himself becoming very cold and calculating while his emotions are repressed. He was not the least bit afraid of lying to or provoking his combatants, using each and every trick he can think
of to overcome the odds. He takes satisfaction from experimenting with his powers by measuring the extent of it to the point where he heartlessly brainwashes and kills people. Everything Ainz aims to do was to
better himself, rack up accomplishments, and master new ways to use his magic and stats in the New World.
Being the collector and hoarder that he is, Ainz spent his time and money in YGGDRASIL amassing a formidable amount of items regardless of its actual value. One-Time Event items share space with easily obtained
common drops in his inventory, as nothing is ever thrown away. These include items which he cannot personally use, such as swords, armors, and scrolls. While most of them are stored in his Item Box, some
are left in his private room in Nazarick and E-Rantel. Also, Ainz's arrival in the New World has since further expanded his interest in other things that now include plants, animals, and even sentient races
that are later "stored" on the 6th Floor of the Great Tomb of Nazarick. He is ambitious and open enough to look for ways outside the tomb to bolster Nazarick as a whole. As the guildmaster of Ainz Ooal Gown, he
loves to reminisce about the wise words from his fellow guildmates as they may hold some meaning now in the New World, which the NPCs wholeheartedly agree to.
Since he is loyal to his friends and the NPCs created by them, he acts with a certain degree of nobility, when leading his devoted followers properly. It was so they can faithfully have a Supreme Being to look
up to and depend on since he is the ruler of the Great Tomb of Nazarick and the last Supreme Being to have stayed with them even after their creators left them behind. It was to this extent that he follows the
whims of his followers' plans hatched up by them, particularly Demiurge and Albedo. To maintain the facade of a glorious and intellectual ruler with tremendous wisdom, he deceptively lets the two greatest minds of Nazarick reach the conclusion that everything they did were part of his long-term grand schemes all along. Ainz would bluff his way out of certain situations like it without the latter noticing his ignorance and incompetence. Ainz allows his two advisors to do the explaining to the rest of the NPCs for him, as he himself had no clear clues or ideas about what they are planning.
However, playing the role of a dignified person is very tiring and stressing for an average salaryman like Ainz, making him feel as though sometimes he would wishfully develop the desire to run away from his
duty while making up excuses to make that situation possible. Despite everything he did for the sake of Nazarick, Ainz has done so to show the NPCs that he does happen to care for them. He considers himself
like a father figure to Pandora's Actor and his friends' NPCs, tending to their well-being and needs first before everyone else. At the same time, he goes as far as to offer them rewards for their diligence.
Due to the harsh work environment, Ainz and his guild members were raised in from the real world, he shows signs of concern for the workaholic nature of Nazarick's residents, worrying that his subordinates are
overworking and pushing themselves too hard without rest. He is willing to make some adjustments to the NPCs' work schedule by including rest breaks into it for as long as need be until they have a full
recovery.
When he was crowned king of his newly-formed country, the Sorcerer Kingdom, this trait also plays a certain key role in earning loyalties among his countrymen. For instance, the Guildmaster Ainzach describes Ainz as being a rational person who makes wise decisions carefully, commending him for being an intellectual, but merciful ruler. Additionally, Ainz is open-minded to others'
opinions of the actions he has partaken, appreciating their criticisms and learning from his mistakes, in which the Floor Guardians can't do to help him. There are also times where he is
nicely playful and other instances when he appears as a bit lonely,Syosetsu Blog Post: March 30th 2013 reflecting on the fact that he has no close companions from his guild to confide his
troubles to or talk with like in the past. Once you have gained his favor and Ainz opens up his heart to someone as a friend, he is surprisingly gentle.
Furthermore, Ainz is not only looked upon as a thoughtful and generous person but also by outsiders of Nazarick who work for him while kindly rewarding them with YGGDRASIL items due to their hard work. In a way, Ainz is true to his word and oath, when he honorably accepted certain conditions made by individuals in the form of promises held to a high degree without betraying them. He has a benevolent nature of ruling over his nation peacefully without bloodshed, figuring there is still always room for reasonable negotiation. Yet at times, however, Ainz would feel paranoid and pessimistic that his Floor Guardians or other NPCs that follow after them may someday abandon him if he doesn't live up to their expectations.
Nonetheless, he only does things that will benefit Nazarick or himself above all else, whether it's information or prestige. Although he does have a sense of justice and doesn't hate humans as much as his followers, Ainz holds no deep attachment to them, and he feels nothing toward their deaths. Ainz does not view humanity as an enemy, but he will kill humans with no hesitation for the sake of advancing his goals. Even so, he wants to avoid conflict with other players, especially the ones who are human and are willing to protect their kind. After killing Shalltear with his own hands, he became a lot more vigilant and hostile against players or other foes with World Items that could possibly harm Nazarick in the near future. 
Aside from the NPCs of Nazarick, the only players Ainz will show the most concern for are his past companions. With that said, he can still come off as ruthless and heartless to those outside Nazarick like the invaders who attempted to rob the home of his guild members and lied to him about getting permission from them. In an act of aggression, it came a point where Ainz would loudly unleash his voice of rage while admitting that he has no attention of letting any of them escape alive and get away with the invasion.
On the other hand, Ainz has a competitive side to him, regarding the actions of players within the New World as what motivated him to not fall behind in terms of technological development. Likewise, everything
he does is all for the sake of Ainz Ooal Gown, the Great Tomb of Nazarick, and the Sorcerer Kingdom altogether. For that reason, Ainz is secretive about the information he may have gained, refusing to disclose anything in case it serves Nazarick's interest. Since Ainz prioritizes knowledge as utmost importance to him, he also likes to participate in doing random experiments with the sole purpose of obtaining valuable information on the New World's inhabitants, martial arts, magic, items, or even their way of life, such as religion.
In his dark warrior persona as Momon, he is viewed by people to be very dignified as a worthy adamantite adventurer, yet not willing to make others uncomfortable around him. True to his nature, Momon is also
very faithful and honorable, when he refused Nfirea's request for the Swords of Darkness, prioritizing them first as it was something he accepted before anything else. While he holds
great trust with his comrades, he refuses outside aid if they happen to slow him down during his job. Let alone that, he would use some of his spare time to exchange greetings with every single adventurer's
group in the Re-Estize Kingdom. Out of respect for his fellow adventurers, he doesn't like to reap the rewards for himself and wants those who took part in stopping the disturbance within Re-Estize to be
paid equally, as well. 
In and outside of the tomb, he is quite mindful of Nazarick denizens' negative behavior towards foreign lifeforms beyond their home territory, feeling that he needs to be very considerate and wise on who to
bring with him on his exploration journey and when traveling to other places like the Dwarf Kingdom. Taking advantage of his authority over Nazarick denizens while in the highest position of power, he will
enforce and impart his words onto them so that they do not act out of conduct in front of him. In the face of his guests at a meeting, this means going so far as to scold and admonish his subordinates if they
speak out of line or turn, correcting their disrespectful behaviors while offering a sincere apology at the same time. 
After staying in the New World for some while now, he starts to realize that his friends may not have transferred with him, accepting the fact that they will never come back. Realizing he is losing interest
over time in bothering to find them, Ainz turns his focus and objective to ensuring the NPCs' happiness over anyone else, while the citizens of the Sorcerer Kingdom come second to it. He even feels motivated to
learn and grow stronger in his own way by accumulating knowledge about what's in the New World that distinguish itself from YGGDRASIL like their unique magics, talents, martial art skills and items. In other
words, he wants to self-improve himself not only as a magic caster, but as both a warrior and a ruler of a nation too, seeking guidance from people who have experience on the job, be it through physical
training under Cocytus face-to-face in a duel or or observing Emperor Jircniv from a distance.
== Background ==
=== In the Real World ===
In the year of 2138 before taking on the name of Ainz Ooal Gown in the New World, Momonga was his original name as a player in YGGDRASIL. But in reality, he was a human being by the name
of Suzuki Satoru, his true identity. Whenever Suzuki left home while heading to his workplace, he wore an air filtering mask and goggles to prevent himself from being affected by the toxic air outside. He used
to be the sort of person who wasn’t bothered by seeing the corpses of orphans since he encountered them so often on the streets that it was hardly a rare occurrence for him anymore.
Early in his life, Suzuki lost his mother when she overworked herself to death. Her death occurred in the kitchen of Suzuki's home, where she collapsed on the floor while trying to make his favorite dish. He
vividly remembered seeing it happen with his own eyes in the morning upon waking up. In terms of receiving fatherly love from his father, he claimed to have never experienced something like that before in his life.
On the other hand, Suzuki Satoru was an elementary school graduate and salaryman who lived alone in a broken-down apartment. Because Momonga did not have any real family or friends to support him, he dedicated his whole life instead to the DMMO-RPG, YGGDRASIL, and just his guild. His life was an endless cycle of going to the office to work. He had often seen kids who had just graduated elementary school working alongside him on the job.Overlord Bonus Volume Chapter 2: The Two Set Off As a salaryman, he recalled how his bosses announced to their employees that they would only begin work once everyone including himself had arrived on time. Thus, all he could do was suppress the urge to go home, because he truly understood how they felt. The kind of people Suzuki hated by far were those who rejected other's opinions without offering solutions of their own as well as crappy customers who knew nothing. For the most part, catering to the clients was paramount to the point where Suzuki even watched soccer games in order to create topics to talk about.Overlord: The Undead Oh! Chapter 82 
Sadly, fun memories of the times he spent with his friends as members of Ainz Ooal Gown were all he had in the game compared to the real world. Momonga's daily livelihood to the game had even gone so far to the
extent where he used up most of the money financially obtained by him from working to have it purely used for YGGDRASIL. His salary earnings were meager, but he still lived above the poverty line. Momonga had
an ample balance in his bank accounts, yet he had no idea how to spend that money. In the end, it was apparent that Momonga had already spent almost one-third of his monthly salary on cash purchases for the game.
=== Nine's Own Goal ===
When Momonga first began playing YGGDRASIL, the idea of killing heteromorphic races was a common practice in YGGDRASIL. At that time, he was one of the targets who was hunted down and killed by PKers multiple
times. Having enough of the harsh treatment, he was very close to quitting the game until Touch Me's words had saved him.
In the anime, he was shown to be surrounded by a group of PKers in their attempt to finish him off while mocking his character avatar. However, as they were about to carry out the PK on Momonga, Touch Me suddenly came to his rescue and defeated them simultaneously. Since then, both Momonga and Touch Me made friends with seven others like them together to form the First Nine, which started out
as a PvP/PKer clan, known as the Nine's Own Goal.
At some point in time, during a meeting with his clansmen, Touch Me thought of disbanding the Nine's Own Goal and wanted to form a guild and recommended Momonga to be their leader. Once the clan was
dissolved and the members present agreed to accept Momonga as the guildmaster, he and friends created an official guild called Ainz Ooal Gown. Carrying out the role as the Guildmaster of Ainz Ooal Gown, Momonga was now tasked with miscellaneous work, such as contacting people in the guild from this moment forward.Overlord Blu-ray 04 Special Prologue (1st Half)
=== Guildmaster of Ainz Ooal Gown ===
Right after the guild was created, Momonga would lead Ainz Ooal Gown and its members to an unknown dungeon called the Great Tomb of Nazarick thanks to the efforts of his friend, Nishikienrai, for locating
it. Due to Momonga's leadership and cooperation with his guild members, it led to the guild being able to conquer the Great Tomb of Nazarick and shortly afterward, also acquiring a World Item called the
Throne of Kings the same moment they cleared the dungeon.Overlord Blu-ray 04 Special Prologue (2nd Half) The dungeon would later serve as Ainz Ooal Gown's future guild base while
dealing with the invasion of players intruding on their location.
On the other hand, there were other players who started to perceive the guild of heteromorphic races as evil beings that must be defeated at all costs. Hence, the guild members of Ainz Ooal Gown, including Momonga, thought that it was only proper for them to become real monsters. It was indicated during the players' invasion of their guild base that Ulbert suggested they should also act as final bosses unless the enemies were able to reach them.
During those years, Momonga and his guildmates spent most of their work and effort focused on building their guild weapon, the Staff of Ainz Ooal Gown. In addition to that, Momonga and his guildmates
created their own customized NPCs, which for him was Pandora's Actor. He made Pandora's Actor to not only preserve the identity of Ainz Ooal Gown, but to serve in protecting the guild's Treasury for
starters. At some point in time, however, nearly 37 out of his 41 guildmates quit the game altogether, leaving the guild and giving away their player's equipment to Momonga. Not only did they quit the game, but
they also deleted their character's avatar completely. This was due to the real-world issues that they had to deal with. He would later store most of his guild members' equipment in the Treasury for
safekeeping. Momonga also made all of the Avataras in the image of his guildmates who quit the game.
Prior to them leaving the guild and YGGDRASIL, Momonga would return straight home after work every day and log onto the DMMO-RPG ahead of everyone else. It was something he did during the era when the guild was
still actively thriving with plenty of members online. There, he would also begin making preparations in Nazarick before his comrades came online. He would summon numerous undead to protect himself as well
as hire NPC mercenaries to hunt down monsters with the guild's goal in funding Nazarick. Extremely dedicated to the game, he was used to playing on his own most of the time when everyone else was offline or
inactive in YGGDRASIL.
Since most of his guild members had already quit the DMMO-RPG, Momonga continued to stay behind and kept their guild base running. He had begun solo hunting areas and farming for things by himself to a nearly
ridiculous degree to earn the gold needed to maintain the Great Tomb of Nazarick. The dungeon seemed to be in top-notch shape according to Herohero, as he apparently had taken notice of Momonga's efforts to
manage it as their guildmaster. Herohero believed that Momonga's devotion to maintaining the dungeon for this long was in hopes that they would one day return to the game and play with him again. Because of
that, he did not bother to build new friendships with other players and avoided them, as well as the high-difficulty areas he used to visit when his guild members were still around. Then, he would deposit his
earnings in the Treasury before logging out. This had been his routine almost daily. As such, he did not have much contact with some of the NPCs and hardly knew a thing about them until now.
Nonetheless, the tedious labor Momonga had spent while maintaining their guild base financially had managed to paid off, as no players were able to conquer the Great Tomb of Nazarick even after the
game's shutdown. This also applied to the number of times and efforts he put forward into the game to prevent the guild's rank being formerly 9th from dropping any further than 29th as its current ranking. Strength-wise, Momonga did it all on his own as he was the only manpower who happen to be active daily within the guild.
== Chronology ==
=== The Undead King Arc ===
Momonga, the guildmaster of Ainz Ooal Gown, is first seen conversing together with Herohero during the last moments of YGGDRASIL before shutdown. Herohero bids farewell to Momonga and logs out for the last time, as he has already quit the game. Mentally, Momonga is enraged about his friends leaving the game, but cools down after noting that they didn't abandon the guild - it was that they had real-life issues to deal with. Still engrossed in the memories of the past, he takes the Staff of Ainz Ooal Gown before heading to the throne room.
Once there, Momonga encounters Sebas Tian and Pleiades in the Royal Suite and calls for them to accompany him. At the throne room, he discovers Albedo holding a World Item. While he
is initially irritated that her creator Tabula Smaragdina broke the guild rules, he quickly forgives him since Albedo was one of his treasured creations. Momonga looks through her settings and reprograms
her to be in love with him. With little time left, he sits on the throne and points at the banners, calling out the names of his guild members while waiting for the server to shut down. Unexpectedly, the server
does not shut down and Momonga quickly realizes that something is wrong when the NPCs begin talking. Staying calm, he orders Sebas to survey the surrounding area on the surface and orders Albedo to assemble the
Floor Guardians on the 6th Floor. Brooding to himself, he concludes that all of the NPCs have gained sentience and agonizes over Albedo's modified settings.Overlord Volume 01 Chapter 1: The End and
the Beginning''
Later on, Momonga goes to the Amphitheater on the 6th Floor and meets with Aura and Mare. He tells the two that he wishes to test out his tier spells, the Staff of
Ainz Ooal Gown, and the radius of Aura's skills. During one of such experiments, he summons the Primal Fire Elemental and asks Aura if she wants to fight it, to which Aura agrees, dragging Mare along. When
they finish the fight, the Floor Guardians start gathering one by one until everyone is fully assembled together and pledge their absolute loyalty to Momonga. Upon confirming their loyalty, Momonga goes back to
the throne room.Overlord Volume 01 Chapter 2: Floor Guardians
Meanwhile, Demiurge, who spots Momonga trying to leave the area, requests that he be allowed to be Momonga's escort outside of Nazarick to see the New World. After seeing the New World, he goes to Mare and
rewards him the Ring of Ainz Ooal Gown for doing a splendid job. He also gives a ring to Albedo and then teleports back to Nazarick. Momonga, using Mirror of Remote Viewing, discovers a village being
attacked by knights. At first, Ainz doesn't want to get involved in the conflict, but when reminiscing about Touch Me, who had once saved his life, however, he decides save
the village. He then teleports to the outskirt of the village and saves Enri Emmot and Nemu Emmot, who are being chased by the knights.Overlord Volume 01 Chapter 3: Battle of Carne
Village'' After saving them, he summons a Death Knight and orders it to kill the knights attacking the village. He saves Carne Village and gathers information about the New World from the 
village chief. He decides to withdraw, but is soon confronted by Gazef Stronoff and his Warrior Troop's arrival at the village. He introduces himself as Ainz Ooal Gown, the
one who saved the village from the knights. After he is thanked by Gazef, his subordinate informs him that the village is surrounded by unknown figures.
Hence, Ainz also comes across these unknown figures who have Archangel Flame with them, similar to that of YGGDRASIL monsters. He realizes that Gazef is their target, and he gives him a 
sculpture for good luck in his battle.Overlord Volume 01 Chapter 4: Conflict All of a sudden, he magically switches places with Gazef due to that item's power and faces
the Sunlight Scripture led by Nigun Grid Luin in his stead. Ainz offers them the chance to surrender or face death. He uses Negative Burst on the Archangel Flame, then uses Hell Flame on
thePrincipality Observation, and finally uses his Black Hole to finish off the Dominion Authority. He easily defeats the Sunlight Scripture and goes back to Carne Village to check on Gazef's condition
before leaving the village. After returning to Nazarick, he announces to his NPCs that he will no longer go by the name of Momonga, but will go by Ainz Ooal Gown from now on, ordering them to make his new name
an eternal legend in the New World.Overlord Volume 01 Chapter 5: Ruler of Death
=== The Emissary of the King Arc ===
Ainz Ooal Gown returns to his personal chamber using the Ring of Ainz Ooal Gown. After much convincing, he dismisses the Eight-Edge Assassins and his hidden insect guards from his room under the
pretense of conducting a secret ritual. Instead, he takes out a set of books he retrieved from Ashurbanipal, all topics in improving his leadership skills. Despite browsing through the contents of the
books, Ainz is insecure in his position as Overlord of the Great Tomb of Nazarick and strives to be the ideal leader. However, he knows his limits as he did not receive a proper education and decides the best
way to gauge his subjects is to have a heart-to-heart talk.
Ainz summons Sebas and inquires him on the Homunculus Maids and their happiness. Sebas Tian answers that the maids are dutifully serving him, and he should not trouble himself with such minor issues, but
the answer does not satisfy Ainz. Ainz wishes to give the maids breaks, much to the surprise of the butler, who feels it's unnecessary, but decides to accept it anyway after seeing Ainz's logic in giving the
subordinates time to reflect and see how they can improve. Ainz feels that his talk with Sebas went poorly and believes the problem is that he is poor at direct conversation. He then has the idea to create a
Death Knight through his summoning magic and have it bring his questions to his subordinates to answer. The Death Knight does its master's wishes, visiting each Floor Guardian and reporting on their responses.
Upon receiving their answers, especially Demiurge's response that he needs nothing to strengthen Nazarick, Ainz realizes that he has been pushing himself too hard in earning their love and loyalty as the NPCs already have gifts from their creators and thus anything he could give him is useless. Ainz decides to follow through with the last person on his survey, that being Albedo. He messages her and asks how she is
and inquires where her room is. To his shock, he learns that Tabula never created a room for her and that she has been living in the throne room since her creation. Guilty at this oversight, Ainz takes it upon
himself to personally give Albedo her own quarters.Overlord Blu-ray 01 Special: The Emissary of the King
=== The Guardians' Vacation Arc ===
Ainz had been tirelessly working for ten hours on end without rest from evening to morning, managing workload and gathering information like the stock of Nazarick's scroll parchment. He orders Albedo to
restrict the creation of new magic scrolls in Nazarick as well as minimize their uses. He also gives Albedo the order of finding materials from the outside to substitute those from YGGDRASIL, understanding that
he needs to rely on using the currency of the New World instead of ones in-game. Realizing how long he had been working until now, Ainz suggested both Albedo and Sebas who were by his side to take some time off
and rest while he continues working. Seeing that this matter cannot be address without the other Guardians present, Ainz decided to summon everyone else for the meeting about it. As a result, Ainz orders the
Guardians to take a break from their heavy work schedule which they accepted, much to their reluctance. Ainz considers the idea of using a fixed time for rest every day, implementing a rotation format, where
they will take turns to rest for a full day each. To set an example for them, Ainz told the Guardians that the way he spends his days off from work is to enjoy playing and traveling with his guild members.
Through giving the NPCs a break, Ainz is hoping to provide them enough rest and nutrition while eating food and sleeping so that they can properly grow up. Before ending this meeting, he had Sebas regulate
changes to the Homunculus Maids' schedule as well.
While the Guardians are on break together in secret, Ainz decided to use this chance to silently spy and eavesdrop on their conversation via [Rabbit's Ear]. Ainz shows concern whether they are plotting to
overthrow him behind the scene without the former noticing. Initially, he thinks to himself that this meeting between the Guardians is happening because his position as the ruler of Nazarick is put into
question. However, over the course of listening to their discussion, he came to an understanding that they were not planning to betray him much to his relief. At the same time, he realizes that now is the time
for him to resume his duty and continue working as their ruler, no longer wishing to listen further from their conversation.Overlord Blu-ray 02 Special: The Guardians' Vacation Arc
=== The Dark Warrior Arc ===
Ainz Ooal Gown, alongside Narberal Gamma, goes undercover as adventurers under the aliases of Momon and Nabe. They infiltrate the fortress city of E-Rantel and register as copper class adventurers.
Along the way, they cause a commotion at the inn, which leads Momon to give Brita a potion for compensation. He discusses his plan to Nabe about their objective in this city. He
plans on becoming a famous adventurer and gather information about this world. They then go to the Adventurer's Guild to search for a job and end up meeting Swords of Darkness, who offer them a job.
After the discussion, the female receptionist informs Momon that someone else had requested him for a specific job. As a result, he meets Nfirea Bareare, who requested Momon to be his escort to Carne
Village while gathering herbs along the way. Nevertheless, Momon accepts both of their requests and their journey begins.Overlord Volume 02 Chapter 1: The Two Adventurers
As they travel to Carne Village, the party is attacked by a large group of goblins and ogres. A battle plan is formulated quickly, whereas the Swords of Darkness are in-charge of fighting
the goblins while Momon and Nabe deal with eliminating the ogres. As the fight proceeds, Momon kills the ogres while Nabe finishes off the rest. The journey proceeds smoothly after the encounter, but things are
amiss as Carne Village is more fortified than usual. Sensing that something is wrong, the party advances cautiously, but are ambushed by the Goblin Troop. Momon realizes that the goblins are in fact Enri's summons through the use of the Horn of the Goblin General for the sake of protecting the village.Overlord Volume 02 Chapter 2: Journey 
Later on, Momon's true identity as Ainz Ooal Gown is eventually discovered by Nfirea. This is due to the clues Ainz left behind in E-Rantel, which Nfirea was able to somehow piece together to help him realize
who Ainz really is behind the adventurer persona. Thus, he apologizes to Ainz for deceiving him and wants to thank him for saving Enri and Carne Village. Nfirea also tells Ainz that the request was just his
attempt to learn more about Ainz's rare potion. After convincing Nfirea not to reveal his identity any further, they head to the forest to gather some herbs. Ainz orders Aura to lure out the 
Wise King of the Forest to him, so he can challenge him in battle. Upon fighting it, however, he is disappointed that the Wise King of the Forest is actually a giant hamster all along and tames it easily.
Momon then shows it to the Swords of Darkness that he has the Wise King of the Forest under his control.Overlord Volume 02 Chapter 3: Wise King of the Forest
They return to E-Rantel, where Momon goes to the Adventurer's Guild, so he can register Hamsuke as his mount and pet. Once Momon finishes Hamsuke's registration, he meets up with Lizzie Bareare,
Nfirea's grandmother, who leads them to her workshop. He discovers that the Swords of Darkness have been killed and turned into zombies. As a result, Momon is immediately left with no other choice
but to kill them, and begins investigating what had transpired while he was away. Momon finds out that Nfirea was kidnapped and tells Lizzie to hire him so that he can save Nfirea. They head to the cemetery and
break through the mob of undead and confront the two instigators. He then has a one on one duel with Clementine and wins successfully, finishing her off with a bear hug that kills her. After resolving the
incident, he leaves behind the enemies' corpses to the authorities as proof that they were the instigators. With the mess settled, Momon and Nabe are quickly promoted to Mithril class adventurers.
Overlord Volume 02 Chapter 4: Twin Swords of Death They return to the inn and discuss what to do with Nfirea and Lizzie. Suddenly, Ainz is informed by Albedo that Shalltear Bloodfallen
has rebelled.Overlord Volume 02 Epilogue
=== The Bloody Valkyrie Arc ===
After being informed by Albedo that Shalltear Bloodfallen has rebelled, Ainz returns to Nazarick and tries to figure out why the vampire has gone rogue. He and Albedo head to the 5th Floor to visit Nigredo
and uses her to find Shalltear. They discover that Shalltear is now fully equipped in her Bloody Valkyrie form. However, Ainz is informed by Narberal that the Adventurer's Guild at E-Rantel is looking for him.
He then goes to the Adventurer's Guild meeting and discusses a powerful vampire. Momon convinces and insists to the Guild leaders, E-Rantel's authorities, and his fellow Mithril adventurers, that he will
exterminate the vampire on sight. When the meeting is over, he goes to the forest and orders Albedo and Mare to dispose of Kralgra, who ignored his advice and chose to follow.
Later, he finds Shalltear and uses Wish Upon a Star, a super-tier spell, which fails to get rid of her mind-control. As a result, he assumes the worst from this experience and learns that Shalltear is under the influence of a World Item unknown to him. Ainz decides to retreat back to Nazarick and begins preparations for his fight against Shalltear.Overlord Volume 03 Chapter 3: Confusion and Understanding Ainz has no choice but to get a World Item from the Treasury. He meets up with Pandora's Actor, his creation and the one who is in charge of the guild's treasury. After talking to Pandora's Actor, he gives the Ring of Ainz Ooal Gown to him before entering the vault with Albedo. Ainz eventually decides not to use the World Item, since he didn't want to put it to waste and that he will face Shalltear alone without outside interference or help. Moreover, he hands some of those World Items to the Floor Guardians instead to protect them from the effect of their enemy's World Item. He then faces off against Shalltear in an intense battle, using many of his spells against her.Overlord Volume 03 Chapter 4: Before the Death Match Finally, Ainz finishes her off with the super-tier spell, Fallen Down, and thus, he emerges victories against Shalltear.
Returning to Nazarick, Ainz resurrects Shalltear and hopes that her death will cure her mind control, which it does. He then starts a discussion with the Floor Guardians about strengthening the Great Tomb of Nazarick's defenses. While doing so, Albedo advises Ainz that the lizardmen might have potentially stronger bodies for him to create more, but powerful undead. At E-Rantel, Momon and Nabe are promoted to adamantite class adventurers after reporting on Shalltear's defeat.Overlord Volume 03 Chapter 5: Player Vs Non Player Character 
=== The Show Must Go On! Arc ===
When Aura begins building a duplicate of the Great Tomb of Nazarick, Mare believes she is going to secede from Nazarick. After Ainz arrives, he explains its purpose to serve as a fake base to fool outsiders in case of an attack. Upon learning of Mare's worry of a possible new rebellion amongst the Floor Guardians, Ainz tries to reward Aura to maintain her loyalty. Despite her reluctance, Aura accepts only if all the other Guardians are similarly rewarded. Later, Ainz calls a meeting with the Floor Guardians on his plan to implement fringe benefit services. The discussion is productive until feedback from Albedo and Shalltear devolves into a duel of words, forcing Ainz to close the meeting early.
Later, during a walk on the 1st Floor, he is greeted by Demiurge, who congratulates him in his scheme of offering rewards, as the demon believes it to be a method to weed out traitors amongst the ranks. Rather than deny it to be not the case, Ainz confirms it to be part of his plan. When he retires to his chambers, he muses to himself on how he can keep his image as a dignified ruler intact and comments that maybe he should try practicing acting. When he returns to work, he is approached by Albedo to include a theatre in the fringe benefit services to provide entertainment for the NPCs. Already receiving the approved signatures from a majority of the Floor Guardians, she proposes that the play Romeo and Juliet be its first production. She insists that Ainz play the part of Romeo, though he is hesitant to accept her request until she mentions it would help his acting skills. However, Shalltear barges into his office, revealing that the play is a scheme concocted by Albedo to steal a kiss from Ainz while she stares as Juliet. Shalltear demands that a fair voting process is instituted to select the main female lead. So, under Demiurge's judgment, a competition is held for the role of Juliet in all of Nazarick.
Three days before the auditions, Ainz watches Albedo practice her lines. Ainz is amazed at her concentration and when she discovers him watching, Albedo asks if he would help her practice. She manipulates him into playing out the scene of Romeo's death, where Juliet kisses his lips. Just before the Overseer Guardian could perform the act, Shalltear throws an attack at the succubus, which results in another argument between the Guardians. Ainz, so disgusted with their immaturity, angrily departs. At the auditions, he witnesses their acts, leading the votes to a tie. The two are ultimately disqualified for bribing one of the judges, Aura. Ainz is about to close the competition until he learns that Mare has decided to participate in the auditions.Overlord Manga Volume 06 Special: The Show Must Go On! Arc
=== The Sealed Evil Tree Arc ===
Ainz Ooal Gown, once again using his adventurer alias Momon, takes on a personal request from the Adventurer Guildmaster of E-Rantel. His mission is to retrieve a rare herb in the northern
region of the Great Forest of Tob. He is assisted by Hamsuke and Aura Bella Fiora, who guides him to the location of the northern forest. The trio encounters a dryad, Pinison Pol Perlia. Through
her, Ainz learns of the awakening evil treant, Zy'tl Q'ae.
Interested, he decides to go and investigate it despite the dryad's warning. Upon the group's entrance into Zy'tl Q'ae's lair, it has fully awakened and on its head is the herb they are looking for. Seeing an
opportunity for an experiment, Ainz summons the Floor Guardians to do battle with the evil treant. Before the battle comes to an end, Ainz delivers the final blow against it and later returns
to E-Rantel with the herb in hand.Overlord Volume 04 Special Drama CD: The Sealed Evil Tree Arc
=== The Lizard Man Heroes Arc ===
Heeding Albedo's suggestion from before, Ainz decides that his next target will be the Great Lake. He orders Cocytus to annihilate the lizardmen and use their corpses to create stronger
undead, so they would be able to strengthen Nazarick. While Cocytus fails to annihilate the lizardmen, Ainz has planned his failure all along so that it could help the warrior grow individually. Through an
NPC Experiment Ainz had committed on testing with Cocytus, and it yielded great results to him, confirming to the former that potential growth and learning is indeed possible for NPCs. On the other hand, the Lizardmen War is also just an experiment to him and Nazarick in order to use that weak army of theirs for observing how the lizardmen tribes fight against low-tier undead forces.Overlord Volume 04 Chapter 3: Army of Death He then changes his order from annihilation to occupation and, as punishment, Cocytus is to be given control and responsibility for the lizardmen
once they have submitted to Nazarick. Ainz and his forces confront the lizardmen and start a talk of negotiation with them. He gives a condition to Shasuryu Shasha and Zaryusu Shasha, that they must
face Cocytus in a battle. If they win, he will no longer attempt to bother the two and their people. However, if they were to lose or decide not to fight, they must readily submit to him under Nazarick's rule.Overlord Volume 04 Chapter 4: The Dawn of Despair 
In the end, Cocytus emerges victorious in his battle against the lizardman heroes. Ainz orders Cocytus to summon Crusch Lulu to his presence. He suggests that Crusch Lulu be his spy within the Lizardman Tribes in exchange for the resurrection of Zaryusu's life.Overlord Volume 04 Chapter 5: The Freezing God After Zaryusu is revived by Ainz, the lizardmen now view him as
their new God who not only has the power of death, but life too.Overlord Volume 04 Epilogue
=== The Search for Hamsuke Arc ===
Ainz, who is working in his study back in the Great Tomb of Nazarick, is informed by Albedo that Narberal Gamma wishes to see him. Narberal asks if Hamsuke has come into contact with Ainz, but unfortunately, he reports that he has not seen the hamster not since she took her to the surface for some fresh air.
Learning that Hamsuke was in-charge of delivering research materials to 6th Floor, although the monsters there have yet to report her arrival, Ainz analytically deduces on the fact that the hamster may have
gotten lost along the way. Ainz agrees with Albedo that they should begin conducting a search for Hamsuke and her whereabouts.
Later, Shalltear reports back to Ainz in regard to how her minions were able to confront his pet on that floor and where she ran off to. When the female Guardians begin to bicker, Ainz decides to have Shalltear and Albedo work together to improve their relationship. Ainz and Narberal then journeys to the 6th Floor to recruit Mare and Aura in their search.
Eventually, Ainz and Narberal end up getting reunited with Hamsuke who manages to find her master while they were looking for her. Ainz orders Narberal to feed Kyouhukou's servant before sending him back to his master. After finding her, Ainz figures that this is also a good way of building a relationship between Hamsuke and NPCs like Kyoukukou, who came to her aid as she was a new resident inducted into Nazarick.Overlord Blu-ray 03 Special: The Search for Hamsuke Arc
=== The Two Leaders Arc ===
Ainz takes a bath by using the slime to wash and clean his bones. At the same time, he decides to invite all male Floor Guardians to enjoy the spa in the 9th Floor together. In his
bedroom, Ainz is seen practicing various different poses and speaking phrases. Ainz sees Mare and asks why he is here. Mare responds that he's handing back the invitation that Ainz wrote. The two exchange words
and Ainz ends up expressing his love for the NPCs. Hearing what Ainz said, Albedo becomes unable to control her emotions and attempts to rape Ainz. Fortunately, he orders Mare and several Eight-Edge Assassin nearby to get Albedo off while punishing her with three days of solitary confinement.
Later that day, Ainz rides Hamsuke to the Adventurer's Guild headquarters in E-Rantel. He spots Enri Emmot, who is about to be detained by the authorities. He comes and guarantees her release from custody.
Curious to the reasons, Ainz asks the Guild leader for the content of Enri's request, and finds out that it is relating to the lords of the Great Forest of Tob. Back at Nazarick, Ainz scolds Lupusregina Beta for not reporting to him and reminds her to ensure the safety of Enri, Nfirea, and Lizzie Bareare.
Ainz, along with Aura, decides to meet the Giant of the East and Demon Snake of the West. He tries to negotiate with Guu, but it ends in failure. As a result, he activates
his Desperation Aura V and instantly kills Guu and his followers. Meanwhile, Aura captures Ryuraryus, who pleads for his life and swears his loyalty to Ainz. He then begins turning the corpses of Guu and his
followers into an undead army and uses them to attack Carne Village. Back in Nazarick, Ainz consults Demiurge about the upcoming dinner that he will treat Nfirea, Enri, and Nemu Emmot to. After
that, Ainz and the male Floor Guardians begin taking a bath together. While Ainz states that he has a good time in the bath, the Lion Golem attack the female Floor Guardians to restrain their ignorant
behavior. So Ainz and the male Floor Guardians prepare to help them, wishing for a peaceful bath next time if they were to have another one.
Nfirea, Enri, and Nemu are invited to Nazarick to celebrate the success of developing the new potion. Ainz requests that Nfirea not to announce the existence of the purple potion after hearing about the attack on Carne Village. Thereafter, they enjoy the luxurious dinner of Nazarick as a reward from Ainz for their hard-work with making the potion.Overlord Volume 08 Side Story 2: A day of Nazarick 
=== The Dark Hero's Story Arc ===
Under his alias as Momon, Ainz is seen counting his savings and allocating the necessary funds to his various projects. He later sensa Narberal Gamma on an errand to collect ore samples for testing the Exchange Box.
Later, he accepts a commission to guide a young noble named Torkel Karan Dale Völkchenheim and his servant, Andre to complete the former's coming of age ceremony. Ainz is initially suspicious of the human's enthusiasm and hostility. He believes that Torkel is an enemy luring them into a trap, but along the way, he realizes he is just another of Narberal's persistent suitors. On their way to the goblin village, the party encounters a Gigant Basilisk. Seeing the beast, Ainz orders the group to run while he disposes of the creature. The battle is witnessed by Torkel, who would pass on the tale to his future descendants.Overlord Volume 06 Special Drama CD: The Dark Hero's Story Arc
=== Ainz Raises Money Arc ===
Ainz gathers the Floor Guardians together in a meeting to announce that he has finally reached a decision concerning the feedback he had received from a survey of all their desires. Since all the requests made
by the Guardians were vouchers involving spending time with him, Ainz tries a different tactic and gives each of them three gold coins. He orders the Guardians to use them at their leisure. They
are allowed to use the money in any way they want, bar one rule: They must not use it to purchase a living being. He also tells them that should the Guardians need assistance in buying items from the human city
E-Rantel, Sebas Tian and Narberal Gamma are available to make the transaction in their stead. After dismissing the Floor Guardians, Ainz, worried about what the Guardian may buy, decides to scout out the
markets in E-Rantel.
In E-Rantel, Ainz dons his Momon persona, alongside Narberal as Nabe. Listening to the praise from some people on his and Nabe's reputation, he is pleased by the status of Darkness, but sighs at the lack of adamantite work. While walking through the streets, he notices a vendor hocking a series of Blue Rose merchandise.
Returning to Nazarick, Ainz is shocked at the idea of the sale of fan goods based on an adventurer team and is impressed that it's profitable. Albedo, seeing him deep in thought, asks him what is wrong, 
but he tells her it's nothing before dismissing the group present. Later, Ainz is reviewing some documents that Albedo has given him, and asks on the status of the coins he gave them, which Albedo happily reports thatthe Guar dians had used them just as the Supreme Being ordered. Pleased, Ainz calls for another meeting, eager to hear how they spent the coins.Overlord II Blu-ray 01 Special: Ainz Raises Money
=== Table Game to Understand Humans Arc ===
Ainz Ooal Gown, wishing for the Floor Guardians to tone down on looking downs on humans, discovers a copy of Hack And Slash Adventure. Finding inspiration and wishing to play a game, he calls some of the
Floor Guardians to play a table game as humans on an adventure. Another point of the game is to give the Floor Guardians a better understanding of humanity. Ainz plays as the Game Master and directs the story. The guardians manage to complete the game by killing the goblin king that was plaguing the human village. However, Demiurge overthinks the exercise, believing that the humans that sent the guardians were in cohorts with the goblins. Ainz, not willing to disappoint Demiurge, allows the story to continue, creating a new plot in which the guardians return to the village and slaughter them and the demon that orchestrated the events.Overlord Manga Volume 10: Table Game to Understand Humans Arc
=== The Men in the Kingdom Arc ===
 and The Men in the Kingdom II Arc
At E-Rantel, Ainz is planning on giving the Floor Guardians a reward for their work and loyalty. Ainz then orders Narberal Gamma to buy and collect iron ore from different locations, so that he can toss it into the Exchange Box.Overlord Volume 05 Intermission Meanwhile, he receives a message from Solution Epsilon that Sebas Tian has betrayed them.Overlord Volume 05 Chapter 5: Extinguished, soared sparks of fire When Ainz is informed about Sebas's betrayal, he orders Pandora's Actor to transform as him and test the butler's loyalty whether or not he really betrayed them.
Once Sebas's loyalty has finally been settled, Ainz teleports to the mansion, and he recognizes that Tuare is the older sister of Ninya and decides to accept her into Nazarick as a
maid, and under the protection in the name of Ainz Ooal Gown. Returning to Nazarick, he's informed by Sebas that Tuare has been kidnapped, which upsets him greatly after swearing his name to protect her. He
orders his subordinate to bring Tuare back unharmed and destroy Eight Fingers.Overlord Volume 06 Chapter 6: Introduction of Royal Capital's Disturbance 
To cover up the rescue of Tuare and Sebas's identity, he takes on the persona of Momon while Demiurge masquerades a demon invasion on Re-Estize so that it can help him increase his fame if the operation is
successful. He also uses Marquis Raeven's request as a way to visit the Royal Capital without garnering suspicions from the populace of that area on why he's here. He sees and saves Evileye from
Jaldabaoth, a powerful demon lord, who besieges the Royal Capital with an army of demons. Jaldabaoth tells Momon that he came here to find an important item in the Royal
Capital. Momon exchanges a few rapid blows with Jaldabaoth while protecting Evileye from one of his attacks, but the demon later makes a temporary retreat.Overlord Volume 06 Chapter 10: The Most Strongest Trump Card 
Outside of the Adventurer's Guild, Blue Roses and Princess Renner gather all of the adventurers that are present within the city to mobilize. Under their
leadership, the adventurers are ordered to counter-attack and defeat the demon army led by Jaldabaoth. In their battle plan, the adventurer is the bow while Momon is the arrow, as nobody except him can fight against Jaldabaoth. When the operation commences, Momon, Nabe, and Evileye find him waiting for them and suspect it is a trap. Momon tells Nabe and Evileye to handle Jaldabaoth's maids while he faces off
against him. During their fight, Momon and Jaldabaoth crash into a building and walk into a secured room, where Mare is waiting for them. There, Ainz hears Demiurge's explanation about the plan to make
Jaldabath the "Demon Lord", due to one of Ainz's previous orders.
Following the plan, Momon confronts Jaldabaoth in a fierce battle and defeats him. Jaldabaoth proposes to Momon that he'll cease the fighting on the condition of allowing himself and his demon army to withdraw.
Overlord Volume 06 Chapter 11: The Final Battle of the Disturbance After the withdrawal of Jaldabaoth and his army of demons, Momon is recognized by the king for his efforts
in repelling the powerful demon. Not only is Momon viewed as the national hero of the Re-Estize Kingdom, but he is even awarded a special sword after he turned down previous offers from the king.Overlord Volume 06 Epilogue
=== The Invaders of the Large Tomb Arc ===
Ainz returns to Nazarick and gathers all the custom NPCs in the Throne Hall, so he can grant honors to the NPCs for the successful operation in Re-Estize. After hearing Demiurge's plan, Ainz finally realizes that the Floor Guardians are trying to take over the world without his knowledge. He has no choice, but to go along with their plan of world domination.Overlord Volume 07 Prologue
Following Demiurge's suggestion, he must find a country to recognize his new nation. Ainz and Narberal Gamma visit Arwintar, the capital of the Baharuth Empire, to meet Fluder Paradyne, the
strongest wizard of the empire. He meets with Fluder in secret and shows his true power to him. Witnessing his power firsthand, Fluder immediately swears allegiance to Ainz. Ainz then orders Fluder to send
sacrificial pawns to the Tomb.Overlord Volume 07 Chapter 2: Butterfly entangled in a spider web 
As Momon, he escorts the workers to the Tomb and prepares to monitor the massacre. In addition, it is his intention to test out the Tomb's defense system to see if it is properly working or not. He chooses the worker group Foresight as his sparring partners and sends them to the 6th Floor, where he fights them in the Colosseum. Hekkeran Termite tries to deceive Ainz, but he sees through his lie and becomes really upset about it.Overlord Volume 07 Chapter 3: The Large Tomb 
After fighting with Foresight as a warrior, Ainz decides to stop playing around and reveals his true power, and instantly defeats three of the members one by one. Although the members of Foresight manage to let
Arche go ahead of them, her attempt to escape ends in failure as Ainz orders Shalltear to chase the magic caster down and give her a swift, painless death. Ainz is also convinced by
Albedo to form a secret unit to search for any possible guild member found in the New World, allowing the Overseer permission to take charge of it without the other Floor Guardians
noticing.Overlord Volume 07 Chapter 4: A handful of hope Afterwards, he orders Aura and Mare to visit the imperial palace with a dragon and tells the emperor if he does not apologize for the
invasion, they will destroy the Empire.Overlord Volume 07 Epilogue
=== The Magic Caster of Destroy Arc ===
In Nazarick, Ainz meets with Emperor Jircniv and his delegation, who officially apologize to Ainz Ooal Gown. After Ainz accepts their apology, Ainz then turns Femel's corpse into a Death Knight right in front of them, which causes the imperial delegation to feel terrified as he just created a Legendary Undead being with apparent ease. He agrees with Jircniv's
proposal to form an alliance with him and Nazarick, and he also accepts the idea of making his new nation known to the surface world.
After the talks are concluded, Ainz gathers the Floor Guardians in his room. Ainz explains to them it is only to require a just cause and in order to avoid creating many enemies against them. He also explains
to the Guardians that turning countries into graveyards will only damage the name of Ainz Ooal Gown. After hearing Demiurge's explanation to the others, he realizes that Jircniv's intention is to form an
alliance with the other countries to defeat him. Ainz then takes Cocytus's suggestion into consideration by crowning himself as the Sorcerer King of the newly-formed nation. While doing so, Ainz tells the Floor
Guardians that he will demonstrate the military might of Nazarick in the battle between the Kingdom and the Empire at the Katze Plains.Overlord Volume 09 Chapter 1: A War of Words 
Alongside Mare, Ainz heads to the Empire's Fortress at Katze Plains. They are welcomed by Nimble Arc Dale Anoch and General Carvain in the fortress to honor
the alliance between the Empire and Ainz Ooal Gown. Ainz is requested by the Emperor to cast one of his most powerful spells to destroy the enemy. Ainz tells General Carvain that his army will be arriving
anytime. While this is happening, Ainz learns from Lupusregina Beta that part of the Kingdom's army, led by Crown Prince Barbro Andrean Ield Ryle Vaiself, has begun attacking Carne Village. Ainz orders her
to monitor the village and report everything. Shortly after, Ainz is completely surprised when one of the Goblin Horns that he gave to Enri ends up summoning an entire goblin army. Afterwards, Ainz's army of
undead are teleported via Gate, and he introduces his troops to them, which makes everyone realize that the small army of five hundred is not to be underestimated.Overlord Volume 09 Chapter 2: Preparations for the Battle 
In the Katze Plains, the Imperial Army starts to separate into two flanks, effectively opening a path for the army of Ainz Ooal Gown. Ainz appears at the front of their army with Mare and Anoch standing at
his sides and starts casting a single bright spell. He surveys the area and concludes that there is no player in the Kingdom and no one who is willing to stop him from casting his super-tier spell. With the
course clear, Ainz successfully casts the spell known as Iä Shub-Niggurath, consuming the left-wing of the Royal Army as a sacrifice to summoned five Dark Youngs. Ainz is overjoyed that he
has broken a new record by summoning this many Dark Youngs and orders them to massacre the Kingdom's Army.
Ainz then takes off his mask and calls upon the Imperial Army to cheer for his supreme power. One of the Dark Youngs returns to Ainz and heads toward the Imperial Army's direction, which causes
every single one of the imperial soldiers to run for their lives, trampling over their own allies. The Dark Young places Ainz on top of its head, and he thinks that after casting his most powerful spell, the
Imperial Army would charge in. However, seeing the carnage inflicted on the battlefield, it is understandable that the Dark Youngs did all the work. Still, Ainz decides to continue his assault while Mare is
left in charge of his army.
In the battlefield, Ainz, sitting on top of the Dark Young, appears to greet Gazef Stronoff with Climb and Brain Unglaus arriving there too. Ainz then asks Gazef to be his vassal in exchange for
stopping this war. However, Gazef politely declines his offer, and instead challenges Ainz to a single duel. Ainz accepts his challenge and asks the other two to be the witnesses of their match. Immediately
after the battle starts, Ainz stops time around them except him and begins using other spells like Delay Magic and True Death altogether to kill Gazef instantly. With his victory over Gazef, Ainz tells Climb
and Brain that he will stop the attack, but demands that they cede E-Rantel and its surrounding area to him. He then returns to the Empire's fortress with all of his monsters.Overlord Volume 09 Chapter 4: Massacre 
Later, in the spring, E-Rantel and its surrounding area become part of the Sorcerer Kingdom. Ainz, Albedo, and his army of Death Knights and Death Warriors enter E-Rantel. Albedo then decides to kill a young
boy who is disturbing their arrival march, but is stopped by Momon. Ainz stops Albedo and tells her that Momon will serve him as the sword of the Sorcerer King, with Albedo accepting his
offer. Afterwards, E-Rantel becomes a peaceful city without bloodshed under the rule of Ainz Ooal Gown.Overlord Volume 09 Epilogue
=== The Ruler of Conspiracy Arc ===
Once the war is over and E-Rantel comes under the rule of the Sorcerer Kingdom, Ainz establishes the city as the new capital of his nation. Under his rule, he has to decide on how to proceed from there in
ruling his nation by implementing new laws, setting up defenses, and establishing a new governing body, all of which are a lot more than he can handle. In addition, he moves to the former Mayor's residence and sets it up as his base of operations.
Also, it is around this time he takes notice of the severe anxiety of the people coming under the rule of an undead and with all the monstrous beasts that are coming into the city. He notices the severe
absenteeism of adventurers having new quests or anything to do as his minions have mostly taken care of all the problems that the adventurers used to take. For the Sorcerer Kingdom, Ainz comes up with the idea
to remodel the Adventurer's Guild, hoping to change the organization's main goal from being a mainly monster hunting group into real adventurers who would explore the unknown. He meets with the city's guild
leader to discuss it, intriguing him with this new proposition. Ainz makes suggestions, such as providing support and training through Mare's new underground training labyrinth constructed to train new
recruits.
However, he has to make his goals known to all adventurers who would come to his kingdom. In order to attract potential new recruits, he decides to head to the Baharuth Empire to spread the word and to obtain
some new supplies for his newly-formed organization. Just before he leaves, he sends Albedo on a mission to act as an official delegate to the Re-Estize Kingdom to start official ties between the two nations.Overlord Volume 10 Chapter 1: Sorcerer Kingdom of Ainz Ooal Gown 
He asks Guildmaster Ainzach to accompany him to act as both a guide and adviser, recommending Ainz to see Osk, who is known as the best weapons merchant in the empire. Along the way, Ainz becomes interested
in a dwarven sword that Osk has in his collection and is particularly curious about the rune inscriptions on it, which bear a striking similarity to his own world. When he sets up the meeting, the two talk a
little about each other and start an official trade relationship. It is at this point where Ainz even allows Osk to see his undead face and is one of the few humans who does not bear any ill will towards his
undead appearance. They also talk about the Martial Lord of the Empire's Gladiator Arena, with Ainz wanting to participate in a battle against him. Since Osk is the current champion's main
sponsor and is a fan of strong warriors, he thinks it will be interesting to see the fight happen, so he sets up a match between the two.
At the Arena, he meets face to face with Go Gin and at that moment, the two compliment each other out of mutual respect. Before the fight begins, Ainz turns off his High tier physical damage nullification
effect to fight on more equal grounds against the Martial Lord. They also make a deal that if Ainz were to win, Go Gin will become a part of his nation to help train his new adventurers, while if Go Gin were to
win, he will eat him, believing he can become more powerful by doing so. After sparring with each other, Ainz finishes the warrior off by striking him with one of the stilettos charged with
Fluder's magic and kills him. Afterward, he begins to revive the Martial Lord, proclaiming his intentions to the people in the arena for all to hear publicly.
He returns to E-Rantel, satisfied with his accomplishments and, at the same time, is confused with Emperor Jircniv's sudden declaration of wanting his empire to become his vassal state.Overlord Volume 10 Chapter 3: Baharuth Empire On the other hand, Ainz is more interested in the rune-mark weapon he saw, inviting him to make plans to visit the dwarves and their nation first while leaving the details of the vassalization to Albedo and Demiurge.Overlord Volume 10 Epilogue
=== The Pleiades Day Arc ===
Ainz summons Yuri Alpha to his quarters to resolve a situation between him and Solution Epsilon. It is revealed that Solution has stolen Ainz's pet, the sapphire slime Miyoshi, and will not tell him
where she has hidden the slime until Yuri compels her to give him up. After learning that Solution's actions were spurned by jealousy, Ainz tasks Yuri to find out if any of the other Pleiades are dissatisfied
in any way and see if the maids have any desires that they wish to be fulfilled. While Yuri searches for Shizu and Entoma, Ainz promises to seek out Lupusregina and Narberal. When
Yuri reports back to him with her results, he is pleased and decides to put forth a proposal that she proposed, to build an orphanage in E-Rantel.Overlord Compilation Movie 01 Bonus: The Pleiades Day
=== The Craftsman of Dwarf Arc ===
Not long after he comes back from his business back in the Empire, Ainz decides to visit and befriend the Dwarf Kingdom. It is his intention to try and establish official diplomatic relations with the
dwarves in the Dwarf Kingdom through trade. More specifically, Ainz's objective is to understand the runes they crafted into their items and whether if there is a possibility that another player has
something to do with them. Fearing that he may encounter possible players along during the journey to the Dwarf Kingdom, Ainz decides to enlist the help of both Aura and Shalltear into his expedition forces
while being accompanied by their familiars. Ainz hopes to give Shalltear a chance to redeem herself from her previous failure and, at the same time, allow her to take in as much experience she can during their
travel together while following his orders.
On the other hand, Ainz enumerates the things he has to do after meeting the dwarves: verify the presence or absence of players, investigate the runes and their origins, and obtain information and samples of
their metallurgy, smithing, and ores.
Also, it is around this time that Cocytus has sent one of the lizardmen to hand his report in. He takes the opportunity to ask the lizardman about the information on the Dwarves, only to be told that he does
not know much other than there was someone from their tribe who had been to their nation before. The lizardman thinks Zenberu Gugu will be the best candidate to ask any information on them for that matter
regarding the dwarves. After the talk, he contacts both Fluder and Ainzach for any more information available. Unfortunately, they happen to know very little about it, so Ainz decides he should head to the
lizardman village himself to ask for the information directly.
Thus, he later goes to the Lizardman Village to speak with Zenberu about the Dwarf Kingdom.Overlord Volume 11 Chapter 1: Preparing for the Unknown Land During his visit, he happens to offer
his blessing for Zaryusu Shasha and Crusch Lulu's newborn child, presenting a gift to the lizardman chief as a reward for his loyalty. He makes arrangement in bringing Zenberu with him to readily act as a guide
during his journey to the Kingdom via Azerlisia Mountain range. Also accompanying him along the way are a few of Ainz's personal picked guards, including Shalltear, Aura, and their
respective minions.Overlord Volume 11 Chapter 2: In Pursuit of The Land of Dwarves 
While visiting the Dwarf Kingdom, he holds a political meeting with the Regency Council and diplomatically negotiates several trade deals between their nations. After talks of negotiations between them end,
he sets off to reclaim the Feo Berkana, looking to drive the invaders, namely the United Quagoa Clans and nests of Frost Dragons led by Olasird'arc Haylilyal, away from the city. Through the use of violence, Ainz forces the two races to swear eternal loyalty to him, which they do out of deep fear due to his terrifying allies and power. After fulfilling his end of the trade deals with
the Dwarf Kingdom, he successfully puts an end to the Quagoa's invasion, as well as the Frost Dragons' rule over Feo Berkana.Overlord Volume 11 Chapter 3: The Impending Crisis Overlord Volume 11 Chapter 4: A Craftsman and Negotiation Overlord Volume 11 Chapter 5: Frost Dragon Lord 
===Shalltear's Travel Diary Arc===
During the night when Ainz's entourage, while heading to the Dwarf Kingdom, camps out in a fortress he created, Shalltear and Aura exchange stories of who they imagine being useful to their master. For Shalltear he envisions herself saving Ainz when Albedo is defeated by a powerful enemy and rewarding her by tell her never to leave his side, while Aura is her saving Ainz from a siege of monsters and earning a day of personal time with him.
The next morning, Ainz greets the two, and asks how their night was. They misunderstand thinking he knew about their fantasies, and began apologizing and begging to be punished. This confuses Ainz who thinks they were having girl talk on their creators which he feels is fine and is part of their right privacy, and is glad they are getting along on the trip. Afterwards he ushers them to head to the Dwarf Kingdom.Overlord IV Blu-ray 01 Special: Shalltear's Travel Diary 
=== Ainz’s Ambition Arc ===
Ainz Ooal Gown becomes uneasy at the continuous surveillance by his followers and, despite his best efforts, has failed to convince the maids in Nazarick to accept his time-off proposal. Ainz ponders how he can improve the maids' situation and comes up with an idea to create a holiday schedule in which the maids will have to accept the breaks and vacation days.
Ainz decides to create a precedent by declaring that he will be taking three days of vacation, hoping that his subjects will follow by example. Unfortunately, after he leaves the details of his 'vacation' to Albedo, she immediately summons the entire Homunculus Maids staff, Manservants of Nazarick, and even the Pleiades to Ainz's quarters. Since Albedo does not know how many maids he will need to help him out during his vacation, she feels it prudent to have everyone take part.
Angst at how his orders have been twisted, Ainz still vows to make Nazarick into an ethical workplace for his children.Overlord: The Undead Oh! Special: Ainz's Ambition
=== Nazarick Mythology Arc ===
Ainz Ooal Gown meets with Demiurge, who proposes an idea concerning world domination. From him, Demiurge suggests that they use faith as a tool to manipulate the human masses to worship Ainz. Ainz finds the
idea to be plausible, though he notes that it might be difficult to incorporate new mythology given the faiths of the Four Great Gods and Six Great Gods. The other Floor
Guardians and Sebas Tian agree that the previous faiths have six hundred years worth of history, but state that they have an advantage, as Ainz still exists and will be able to encourage a following faster.
They convince Ainz that he needs mythology that is worthy of him, and he agrees to their input. The stories Ainz is told reflects each of his subjects' perception of him and their own versions of the ideal god.
Ainz is unable to decide and doesn't have the heart to reject them until he decides to have the Guardians combine the best part of their myths into a single one. Unfortunately, this results in a more outrageous
story and, to the shock of the people in the room, he decides to cancel the myth idea.
=== The Phantom Ship of Katze Plains Arc ===
 and The Phantom Ship of Katze Plains II Arc
=== The Paladin of the Holy Kingdom Arc ===
 and The Paladin of the Holy Kingdom II Arc
In E-Rantel, a meeting takes place between the Holy Kingdom and the Sorcerer Kingdom, during which Ainz is requested by Remedios to bring Momon into their nation to fight against Jaldabaoth, but Ainz humbly refuses in doing so because of political reasons involving the ongoing situation in E-Rantel. He enlightens them that those among his country's citizens who have little contact with the undead armies he has made have not come to fully accept them yet. Ainz also tells the envoys that he will need more time for the undead to be completely welcome by their human inhabitants and needs Momon to listen to their concerns. Ainz states that if he sends Momon out right now, then there is no telling how the discontent of the people of E-Rantel might erupt into uprisings afterward.
Furthermore, Ainz asks the envoys if the Holy Kingdom has anything to offer to him in case he does aid them in their fight against Jaldabaoth. Gustav speaks up, saying they have nothing
right now, and it will take time for them to recover and prepare a reward in return. He also makes it clear to Ainz that Jaldabaoth is a present threat to their nations, as he is leading an army of demi-humans. Ainz still refuses, stating that he needs more time for everything to sort out. Albedo tells him that it will take at least five years minimum for the relations between humans
and demi-humans in their nation to be solved by then. Due to Ainz's generosity, he responds to the envoys' request by shortening it to three years instead until they're able to come to their aid on time. As a
result, Neia thinks of having a chance to talk it out with Ainz and voices her opinion publicly, which he questions later who she was.
Right after Neia introduces herself to Ainz, she urges him to let their nation borrow Momon as soon as possible, since they can't afford to wait that long. Before Remedios attempts to reprimand her, Ainz stops
her from doing so, and he then asks Neia when it will the best time to bring him along during the liberation of the Northern Holy Kingdom. Neia replies to Ainz, saying that he should send out Momon as quickly
as a possible or one-day minimum is the very least he can do. When Ainz inquires her if it will end up hurting his nation in the process, Neia says that as long as it is for the safety of her nation, then she
is willing to accept it.Overlord Volume 12 Chapter 2: Seeking Salvation
After the meeting, Ainz casts an invisibility spell on himself and waits for Neia outside the inn. He surprisingly spooks her out of nowhere, guiding her to a certain location with no pedestrians passing by.
Ainz tells Neia that he wants to speak with her superior in private, convincing Neia to let him climb through the window. Upon entering through the window opened by Neia, Ainz again confronts Remedios and
Gustav twice now during their second meeting in regards to their request from last time.
After introducing himself again during a meeting with the Holy Kingdom's envoys, Remedios later obliges to Ainz's request and begins moving to a new area for a place to talk privately. He also asks Neia to take
part in their political discussion, which Gustav too heeds to another one of the Sorcerer King's demands as she accepts it. Arriving at their destination, the meeting begins right away when Gustav is the first
to start the conversation, inquiring the Sorcerer King for why he has come here in the first place.
Thus, Ainz briefs them with his main attention from their last meeting, reiterating the fact that he will employ an entity equal to Momon's caliber. Ainz then replies in regard to the resistance group, which
shocked the envoys. In a way, Ainz is already aware of the Holy Kingdom Liberation Army's predicament in the front-lines of war to their utter surprise. Ainz begins to explain their circumstance in full
detail, he states that the South's military strength remains untouched, but yet they do not seek to cooperate with the north and conduct joint operations on their own. Ainz believes that it is like this because
there is a rift between their people and the southern nobles. Ainz even calls the envoys out for their own failure in protecting the Holy Queen, as it is going to be the reason for why the South plans to take
ownership of whom the new Holy King will be after their Queen dies in battle. Aware of the southern nobles' nature, Ainz retorts to the envoys that they don't have much of a say in all this
when the group cannot hold onto their positions for long without the Holy Queen to support them. Ainz concludes to the envoys that they have nothing left to offer him, be it land, titles, trade concessions, or
other such privileges. He also warns them that if the Northern Holy Kingdom actually keeps their words on this matter, the possibility of war with his nation exists, depending on what conclusions the next Holy
King reaches.
Additionally, Ainz enlightens the envoys of not using their nation's treasures as a bargaining chip, with the holy sword belonging to Remedios to be an example. He states that if they do such a thing by trading
something like that of national value, then the most they could do is treat it as having been plundered by Jaldabaoth and later turning the country's treasures over to him after defeating the demon. However,
Ainz calls it dangerous as there will be an informant briefing the next Holy King that said wealth was actually obtained from one of them, which will create a seed of distrust in the group.
Ainz began stating his own conditions and wants something else in return for assisting them, such as having control over Jaldabaoth's demon maids. He believes that Jaldabaoth's underlings may be under the
influence of either his skill or magic item used on them. Ainz tells Remedios that he needs strong individuals to be incorporated into his nation anyway to increase their military strength. Remedios tells him
even if that was the case, she doubts those conditions made by him will be enough for her people to forgive the maids if they're involved in Jaldabaoth's plan. Ainz then tells the envoys that it's the Holy
Kingdom's problem to deal with in swaying the citizens to let go of their hatred or else. He then tells Remedios that he dominated the maids with his magic.
Henceforth, Gustav agrees to all of the conditions listed by Ainz. While doing so, Gustav brings up the question of who is on the same level as Momon. Ainz answers his question by stating that it is he himself,
meaning he will be the one participating in their war efforts. To their bewilderment, Ainz tells Gustav and his fellow envoys that he is going to take care of Jaldabaoth, declaring to them that he is just as
powerful as Momon, if not stronger than him. Furthermore, Ainz tells them that unlike Momon, he can actually use magic like teleportation. To keep the envoys at ease, Ainz states that as long as he can find
their base, he can safely return to the Sorcerer Kingdom at any time. Although Gustav is reluctant to bring a king from a foreign nation to fight their country's enemy, Ainz tells him that he wants to go there
and defeat Jaldabaoth while taking control of his servants through his magic. Ainz declares to them that he will not bring an army with him and that nobody other than him alone can defeat Jaldabaoth.
While helping the Roble Holy Kingdom, Ainz has chosen to temporarily give away some of his items like Ultimate Shooting Star Super to Neia as an aid. After defeating Buser, the Sorcerer King loots the
Bafolk's items for himself and, among them, he hands over its magic armor to the girl for additional protection.Overlord Volume 12 Chapter 3: Beginning the Counterattack
When the battle unfolds between the paladins and the three demi-human generals, Ainz stands by and watches their match while using the [Perfect Unknowable] spell to hide his presence. At some point, he cancels
his spell and decides to assist Remedios, but she leaves him alone to settle her incomplete match with the demi-humans. Frustrated by Remedios's ingratitude after saving her life, Ainz decides to take his anger out on Nasrene, Vijar, and Halisha, killing all three of them fairly quickly. Afterward, he goes around killing the demi-humans that invaded
Loyts, as well as summoning multiple Soul Eaters to aid him. Along the way, he later revives Neia, who died valiantly fighting against the demi-human army.
Ainz returns to his room, where he contacts Demiurge for a meeting in Nazarick with him and Albedo. Neia enters the room to express her gratitude towards Ainz. Ainz informs Neia that he will return to his
country for a while and asks Neia if anyone saw the power of the bow that he lent to her. He is disappointed to learn that those that did see the power of the bow were slain, which is unfortunate, as he failed
to promote the rune weapons. Though Neia informs Ainz that the people whom he saved wish to express their gratitude towards him, Ainz tells Neia to inform them that he's glad to receive their gratitude. Neia
then leaves to convey his message to them while Ainz returns to Nazarick.Overlord Volume 13 Chapter 4: The Siege
While in Nazarick, Ainz is greeted by Demiurge, Albedo, and Lupusregina Beta. Ainz discusses the course of their activities in the Holy Kingdom. Ainz decides to change part of the plan to spread the news of his
death, which causes Albedo to protest the idea while Demiurge calmly accepts the idea. The two begin to argue, only for Ainz to calm the two down and asks what would they do if he died. The two have conflicting
plans and argue about priorities. Ainz then begins them back to focus on who reasons their very argument was the basis of his rationale. Ainz states he wishes to use this exercise to see how the rest of
Nazarick will react in the event of his death. He assigns them to prepare the rest of the Guardians and NPCs for disaster drills. In addition, he asks Demiurge to order his summoned Evil Lord to fight a serious
battle with him the next time they meet.
Back in Loyts, Ainz meets up with Neia again and they continue discussing when a wall of flame appears, signalling that Jaldabaoth has arrived. Both Neia and Ainz fly to the prince's meeting room on how to
proceed, but before they can finish their talks, Jaldabaoth bursts in through the wall and greets everyone along with the demon maids. Jaldaboath meets the Sorcerer King and challenges him to a duel, which the
latter accepts. Many are worried, especially Neia, as he claims to have already used much of his mana. Ainz proceeds to the main city square, where he meets up with Wrath and the Maids. They fight as
instructed, giving Neia and the rest of the Holy Kingdom's residents who are watching afar a comprehensible battle. Shortly after, Ainz seemingly falls in the distance and the Demon Emperor descends in front of
the crowd, badly beaten, but still alive. The demon then declares that the Sorcerer King was a worthy opponent, but using his power to save the people was his folly and his demise.
Many in the Liberation Army despair at their ally having been killed, though Neia refuses to admit that Ainz was killed. Jaldaboath retreats after Neia threatens him with her bow.Overlord Volume 13 Chapter 5: Ainz Dies Despite the loss of Ainz, he supposedly uses the last of his magic to free one of the Demon Maids, CZ2128_Delta, who changes her allegiance and aids the Liberation Army. Ainz's disappearance, however, is the catalyst that causes Neia to seek him. In doing so, she becomes pivotal in rescuing the Zern price Beebeezee, gaining a needed ally in freeing the city of KalinshaOverlord Volume 13 Chapter 6: Gunner and Archer and making her a famed hero. Her fame leads her to create a movement close to a cult of worship of the Sorcerer King.
Ainz does eventually return as a pivotal battle between Jaldabaoth and the Liberation Army. During his disappearance, he claims to have fallen in the Abelion Hills. While there, he slowly liberated it and
formed a new alliance with the freed demi-humans. With an army at his back, he returns to the battle and fights Jaladabaoth once more, this time defeating Jaldabaoth, and the remaining demi-human alliance
quickly scatter.Overlord Volume 13 Chapter 7: Savior of the Nation
The Sorcerer King and Shizu then prepare to return to their Kingdom, while Neia, along with her followers, bids them farewell. Ainz is grateful for Neia's services and offers her to join him. He even offers her the chance to revive her parents as a reward for all she has done. But Neia refuses, as it is too much to give to a mere squire and that her duty now is to restore her kingdom back to its full glory.
In the carriage, Ainz contemplates all the events that have transpired. He asks how Shizu is doing and is delighted that she has made a friend and promises that in the future, she can spend more time with Neia.Overlord Volume 13 Epilogue
=== The Witch of the Falling Kingdom Arc ===
While strolling the main streets of E-Rantel alongside Momon and Nabe, Ainz makes his intention clear to the public that he is still working together with the adamantite adventurers of
Darkness. This is to validate his mutual cooperation with the group, as well as to clear up any misunderstandings or false rumors about him and these two adventurers. It is also revealed that Ainz has lent
out the Hanzos to Tira for the sake of giving her partners to help her train and grow stronger as an assassin. Ainz is even willing to silently consult with Pandora's Actor on the future
advancements and policies of the Sorcerer Kingdom along with how far current progress is being made for their nation at the moment. Along the way, Ainz receives an urgent call from Entoma to return to Nazarick. Ainz obliges to her request and instructs Narberal to bring the rest of the maids back with him too.
Once in the Audience Room with the Floor Guardians, he learns from Albedo about what has transpired with the Sorcerer Kingdom's trade caravan of grains during its transport from the Re-Estize Kingdom to the Holy Kingdom. Ainz is given a witness by the name of Hilma Cygnaeus, who he then casts the [Dominate] spell on to interrogate about the situation. After answering his questions, he declares to the Floor Guardians that she has no part whatsoever in this incident and that it was beyond her control. Rather than giving Hilma a severe punishment, he decides to punish the woman by having her prepare a set of all the plans she can think of within two days to make up for the mistake, submit them to Albedo, and wait for approval.
When that matter is concluded, Ainz commands Shalltear to escort Hilma out of the meeting before shortly returning to the Audience Room, where the discussion resumes. Ainz states that he believes Philip did
what he did without thinking his actions through first. Although Albedo has doubts about seeing such stupidity from the nobleman, Demiurge supports his master's opinion, considering that the noble being an
idiot could explain his irrational action. Ainz then asks for the opinions of the other Floor Guardians besides to voice their thoughts on this matter. The meeting ends with everyone agreeing to follow through
with Ainz's plan regarding the Candy and Whip policy, along with the decision to punish both Philip and the Re-Estize Kingdom.Overlord Volume 14 Chapter 1: An Unexpected Move
Later on, Albedo, who represents the Sorcerer Kingdom as its country's prime minister, visits the Re-Estize Kingdom to relay Ainz's message to King Ramposa III and his courtiers. Ainz's message is retold in
Albedo's words, informing them that he has no clear intention of ever using his grand magic again in this all-out war between their two countries like last time with the Massacre at Katze Plains.
After a month passes since their declaration of war against the Re-Estize Kingdom, Ainz arranges another meeting with those involved in the campaign effort, notably Demiurge, Albedo, Cocytus, and Shalltear. He
looks over the details and discusses how successful the Sorcerer Kingdom's war with the Re-Estize Kingdom is turning out to be without any problem occurring. He praises and acknowledges the success of the operation and the various kinds of maneuvers that were thought out by all the Floor Guardians who participated in it. He orders the Floor Guardians to continue making as many unique strategies as they can against the Re-Estize Kingdom.
While overseeing the war taking place in different places throughout the Re-Estize Kingdom, what stands out to Ainz is the fact that he senses his mental bond with one of the Death Knights and Death Warriors disappearing from the battlefield. He immediately discovers that it is being caused by an armor-clad unknown foe using a YGGDRASIL item known as a Powered Suit to easily dispose of his two undead soldiers. Although he thinks it was the work of a player, Ainz learns from Albedo that it was the deed of someone from the adventurer team Red Drop. Ainz decides to carry on the act that everything went according to his plan, making the Floor Guardians who are present with him realize that it is the former's ploy all along to ensnare the enemy into their trap. They think Ainz intentionally sent in a weak force into the city E-Naeurl for that very reason, without needing to worry about the loss of a puny force by the foe.
It is also revealed that Ainz has taken charge of leading that siege battle against the city in the first place is because of a private discussion he had with Sebas, Pestonya, and Nigredo in the
Frozen Prison. During that discussion between the four of them, he is informed by the butler about a new food culture slowly growing at the city E-Rantel. He is even given a suggestion by Nigredo to let
people rent out more of his undead for the sake of agricultural purposes, the latter justifying to the former that it will develop and improve the breeds of food. With that out of the way, Ainz orders them to
get to the point of the main topic about why he is visiting them. After Nigredo voices her intention of not only herself, but Pestonya and Sebas too, he has chosen to ask them why they have not asked for
permission from their other superiors, the Floor Guardians first rather than him.
Hearing a response from Pestonya for another suggestion, he implores them to give him a reason on why a massacre of the Re-Estize Kingdom should be avoided. He tries to reason with them that this is being done
for the sake of strengthening the Sorcerer Kingdom, all for the greater good of prepping Nazarick against powerful foes like players in the future. He argues their points in several ways, one of such being that
he was against the idea of having human civilizations become too strong. Ainz makes his intention clear by stating that not all humans will be needlessly killed off, as some, like young children, will be kept
alive for nurture. However, when Pestonya brings up the idea of letting humans escape alive as a way for them to act like fearmongers who can spread the news of opposing the Sorcerer Kingdom to be hopeless, it
leaves Ainz contemplating for a little while longer over that suggestion.
Considering the kindness his guild members like Touch Me, Ankoro Mocchi Mochi, and Tabula Smaragdina showed him, he decides to take Pestonya's idea into consideration. Ainz tells them the Sorcerer Kingdom/Nazarick has already managed to convince multiple nobles to join their side. Along the way, he reminds the three of them that only 90% of the Re-Estize Kingdom's people are planned to be wiped out while the rest will be allowed to live on. The conversation ends with Ainz looking to decide what will be the appropriate amount of humans to spare, like a few hundred, out of appeasement for their sake. Knowing that a vast majority of the people in the city E-Naüru survived due to Red Drop appearing, Ainz is able to get a chance of possibly fulfilling his promise to them.
Returning to the present time, Ainz inquires Albedo how credible their intel is, to which the latter believes their foe is from Red Drop due to the adventurer plate being adamantite and having their signature color to represent them. Hearing this, Ainz reassures her that he is just checking to make sure what details she has, which he did not know about until now. While doing this, he even asks for the opinions of the Floor Guardians whether their foe is really a member of Red Drop or a mere ploy all along created to assume their identity otherwise. In the end, he and the Floor Guardians believe it to be the former, as evidenced by Albedo. Upon realizing that none of the NPCs present know anything about Powered Suits, he begins informing the Floor Guardians about what they are with their foe being equipped with one of it as an example. He allows the Floor Guardians permission to go out of their way to borrow and test a few Powered Suits left in the Treasury so they can have a feel of it for themselves.
Leaving aside the discussion about the Powered Suit for a later time, Ainz asks Demiurge about their next course of action to take on dealing with the port city. Hearing Demiurge's response of wanting to send a
stronger entity than their foe to destroy the city, he mentally opposes the idea as it will go against the promise he made with Pestonya of saving the people there. With that in mind, he adamantly voices his
objection to the Floor Guardian's suggestion and instead suggests the idea of laying siege to the Re-Estize capital and all of the other cities. By having the Floor Guardians follow through with this idea
of his, Ainz is giving the inhabitants from E-Naüru the chance and time to run away while they still can during the massacre that will take place in different locations but it. Ainz, on the other hand, orders
Shalltear to bring back the undead they had sent using [Gate] and gather their forces, including the Nazarick Master Guarders, in E-Rantel and has her begin initiating the siege on
the enemy's capital city.
Ainz ends the discussion by reiterating their conquest of the cities one by one and staging the final battle at the capital as planned, along with massacring the inhabitants of every city with the exception of
E-Naüru afterwards.Overlord Volume 14 Chapter 2: The Beginning of the End
When Ainz reaches the Re-Estize capital, he has his 10,000 undead army in a standoff with the Re-Estize Kingdom's 400,000 men army without either side making a move on each other. At the same time, Ainz orders
the three-sided tarpaulin tent that is currently being used as their mobile headquarters to be transported to where he is at through physical means. It is revealed that since his undead army does not require
food resupplies, he is able to command them to form several fronts around him to a smaller size than what a conventional army could normally do with support of Mare's magic. Before long, he is asked by 
Re-Estize's new king, Zanac Valleon Igana Ryle Vaiself, to have an audience with him in private through Albedo. He tells Albedo to start preparing a reception and drinks for his envoy. However, the Overseer
suggests that he turn down the offer since there is no point in listening to someone who is not going to come here to initiate the battle, advising him to take the initiative and start the battle instead.
Despite her reasoning, Ainz frankly reminds Albedo that rumors of what he can do can still be spread by magical means. With that said, Ainz also tells the Floor Guardians that he will be having a discussion
with Zanac alone without bodyguards, much to Albedo's concern. Ainz reassures her that he has someone like Aura to protect him in case the worst does happen, such as being brainwashed or mind-controlled by the
manipulator of Shalltear. In the end, he obliges to the envoy's request for an audience, choosing to ride on his Soul Eater and reach the intended destination Zanac is currently at.
Upon meeting each other, he is immediately greeted by Zanac with an introduction to who he is. Ainz magically arranges two black thrones, a table, and a drink of war to arrange an appropriate meeting spot for
them. The meeting then begin when Zanac asks for the reason behind his heinous acts and why Ainz has chosen not to accept the Re-Estize Kingdom's surrender. Ainz reasons that they have nothing to gain from
seeing them surrender to the Sorcerer Kingdom. Rather, Ainz makes his intention clear by declaring upfront to Zanac that he intends to sacrifice his people as an example to the world of what will happen to them
if they stand at odds against the Sorcerer Kingdom. To that end, Ainz informs Zanac that he and his nation will all be eradicated, and the Kingdom will be rendered into a mountain of ash. Ainz describes such a
mountain to be the kind that will continue to serve as a warning after centuries and millennia of how foolish of an act it will be to go against the Sorcerer Kingdom. When Zanac asks what his goal is, Ainz
thinks about his former guild members from the past and tells him that all he wants is happiness, something which he finds difficult yet also easy to obtain. He even goes out of his way to tell the king that
humans are not alone in looking to find happiness, but monsters like him as well. To Zanac, Ainz admits no one else's happiness matters more to him whatsoever, except for those who he holds dear. Ainz tells
Zanac that he doesn't mind the idea of trampling on others' happiness to achieve what he wants and for the sake of his subjects' happiness. Continuing to answer the next question imposed by Zanac, Ainz says
that there are no other tried-and-true methods he knows of, but what he is doing now to achieve such happiness. Ainz notes that to grant his subjects' happiness, he needs to eradicate Zanac and his people as it
is what the basis of this war is all about.
Once it is finally Ainz's turn to ask questions to Zanac, he inquires the latter about whom the current possessor of the Razor Edge is, to which Zanac reveals that Brain Unglaus possesses it. Hearing this,
Ainz plans to later order Cocytus to retrieve the Razor Edge from Brain if he is spotted in the capital city. He promises Zanac that he will make sure to kill him and his people off as gently and painlessly as
possible, so there will be no constant suffering on their end. After the meeting is concluded, he parts ways with Zanac and returns to his undead army's side, where his subordinates, including the Floor
Guardians, are waiting for him on standby. He later learns from Albedo that there has been a commotion in the enemy's camp. He is presented Zanac's head by the envoys who arrive in his camp to swear their
allegiance to Ainz, wishing themselves and their families to be spared from the massacre that is about to come. Obliging to their pleas, Ainz orders Albedo to give Zanac a proper burial and to send the envoys
to Neuronist Painkill and have her handle their fate. In addition, he orders the Floor Guardians to not let a single person escape alive, ordering Aura, Mare, and Cocytus to kill them all from that point
onward.
Before the battle in Re-Estize begins, Ainz makes sure to switch places with Pandora's Actor ahead of time. While Pandora's Actor is away playing the role of the Sorcerer King as his Doppelgänger, Ainz, on the
other hand, stays back in Nazarick to oversee the battle that is about to take place.Overlord Volume 14 Chapter 3: The Last King Particularly, Ainz, along with Demiurge and Shalltear, watches the fight between Pandora's Actor, posing as him, and the warrior Riku Aganeia play out via a Mirror of Remote Viewing. Not long after the battle is over, when Pandora's Actor and Albedo
return to Nazarick on the 9th Floor, Ainz Ooal Gown congratulates them, along with Shalltear and Demiurge, for the amazing work they have done. While the latter apologizes for their late arrival, he tells them
to not fret on it, as what matters to him is the intel the two have gained from their battle with Riku. Ainz asks for a report on the battle Pandora's Actor had with his opponent, including the conversations surrounding the two. Although he is of the opinion that Pandora’s Actor, who was locked in combat with Riku for longer, would be able to make the more accurate judgment, Ainz considers that Shalltear, who had
been observing the battle alongside him, has estimated a similar level range to Albedo. Nonetheless, he finds it intriguing that the three see Riku as a tank that specializes in magic resistance. Although
Albedo berates Pandora's Actor on his behavior of kneeling before Riku, Ainz believes that the performance from his NPC was executed perfectly, as Riku has been effectively fooled into thinking "Ainz Ooal Gown"
is the weaker one between the two combatants.
The subject of the barrier that prevented Pandora's Actor from escaping is brought up. While Pandora's Actor still cannot figure out what that phenomena was and why Albedo was able to penetrate it so easily
whereas he was trapped, it is Ainz who provides him with the clarity that Albedo was able to enter it was due to her World Item. In addition to that, proof also lies in the fact that Ainz, who was observing the
battle, noticed that the barrier could only be breached when holding a World Item. When Pandora's Actor asks him for his thoughts on the [World-Isolating Barrier], along with whether it was a special skill that
only higher level beings could obtain, Ainz believes that it will be impossible to accomplish what Riku has done through the same system their powers come from. He reasons that it is possible to achieve the
effect through the expenditure of HP, which can be an activation condition for a World Item. However, Ainz admits that he has never once heard of such a World Item where the user's HP isn't continuously reduced
to maintain the barrier, which Pandora's Actor confirms from his fight with Riku. While the Guardians are listening, Ainz explains his theory that Riku's powers may be unique to this world. He thinks that
losing to Riku the next time if they meet again in battle will be necessary to gain more information. While it is a perfectly logical conclusion, if there is a possibility that their master cannot be revived,
Albedo insists that he remain in the safety of Nazarick, which Ainz is reluctant on doing. He reprimands them by explaining why he cannot oblige, to which none of them can understand, much to his
disappointment.
The discussion then turns to the identity of Riku Aganeia, on whether he is a member of the Thirteen Heroes or the Platinum Dragon Lord. Based on Riku's connections to platinum, Ainz ponders to the Guardians
whether he is trying to fool them into believing that he is the Platinum Dragon Lord or one of the Thirteen Heroes so that they will go to war against them or not. As Ainz believes the answer might lie in
between those two extremes, he asks the Guardians to think whether or not what he said is right. In the end, Ainz is uncertain of who Riku really is, as the Guardians have too little information to go by to
fully identify this foe's identity, with Ainz believing his fake name to be just a fake alias. However, to find answers on their quarry, Ainz decides to move forward with plans to reach out to the Council State
and determine if the leader of the nation is in fact Riku.
Just as Ainz Ooal Gown is about to dismiss the meeting and give Pandora's Actor new orders, Shalltear inquires if the offer in taking Riku as a subordinate is true. Ainz admits that it is a lie, as he is unsure
if he can reign such a potential threat under his control. However, Albedo is convinced that killing Riku will be a waste and proposes a plan to convert the warrior to their cause, at least until they can gain
enough information on Riku to determine if he is too much of a threat. Ainz decides to allow Albedo to handle the affair and trusts her judgement. With Pandora's Actor fulfilling his duty, Ainz decides it is
his turn to return to the capital and finish their operation as planned. Before heading out to the Re-Estize, Ainz had ended up working together with his subordinate Mare to destroy multiple structures in
their wake along the way to the Royal Capital.
After reaching Re-Estize, he infiltrated the Ro Lente Castle and enter the throne room. He sat upon the throne that was once seated by King Ramposa III who is now dead and lifeless before him after Renner
murdered her father. Remembering Climb from back during his one-on-one duel with Gazef Stronoff, he had Demiurge undo his [Command Mantra] control over the human. Seeing how Climb proceeded to take Razor Edge
off the ground and fight him, Ainz got up from his throne and slowly strides toward the human warrior. Ainz declares that the one-on-one duel between him and Climb will decide on the ownership of Gazef's
weapon, Razor Edge, promising to defeat him and claim the blade. He mockingly toys around with Climb, lecturing how he doesn't have things like plot armor or dormant power from fairy tales to protect a would-be
protagonist like him from his demise. Ainz refuses to answer Climb's question concerning the fate of Renner's life, hoping to use the warrior's concern to his advantage and torture him in that manner. Before
ending Climb's life, he tells the warrior that death is the only way out for him, as he would no longer suffer from the inequality and injustice of the New World. After killing Climb with [Grasp Heart], he
became interested in conducting new experiments with Razor Edge and if the weapon is capable of damaging a World Item.
Ainz accompanied by Albedo orders Marques Raeven and his entourage of nobles to come meet the two at Ro Lente Castle. He informs them that they should keep on managing their
demesnes per usual and follow the same laws that the fallen Re-Estize Kingdom has maintained before their destruction. He tells the nobles to adhere to any new changes Albedo may notify them of in the future
when the preparations for the Sorcerer Kingdom are finished. He reminded them that the forces of the Sorcerer Kingdom will be returning to his side after they complete their mission of destroying the land of
the nobles to the West and to the South of the Royal Capital. Ainz sternly tells them that he will be preserving the mountain of ashes left by the Sorcerer Kingdom's destruction of Re-Estize as a reminder for
any nation who may oppose them in the future. He orders Albedo to bring Guren outside the tomb to Re-Estize so that the Area Guardian could completely burn all of the Royal Capital except for Ro Lente
Castle all to the ground, all the while bringing the palace's furniture and whatnot to E-Rantel. To stop any plague from taking root in this tragedy, he states his plan of applying magic to prevent that from
happening after Guren fulfills the task. He then instructs Albedo and the nobles to not allow anyone from the Sorcerer Kingdom to ever step foot into the Royal Capital.
After returning to his office, Ainz commanded the maids to leave him alone, as he needs some spare time to reflect on his future plans for the Sorcerer Kingdom. Upon being left to his own devices, he
immediately agonized over the thought of whether his way of acting in Nazarick's latest grand schemes was successful, and his wariness of Renner possibly seeing through his facade. Although he thought of
exposing himself as a talentless hack to the denizens of Nazarick, Ainz chose not to follow through with that idea as the former was yet to be mentally prepared. With enough reflection on his end, Ainz finally
discovered a good idea to use one of the various paid leave plans he offered the NPCs in the past. Ainz said such a ploy can be heavily emphasized by the preparation he had done for the training of the NPCs to
be self-sufficient without his presence around. Considering how workaholic the Floor Guardians have become due to the increased workload, Ainz believes this would also be a good experiment to see how well
Nazarick would fare under Albedo's leadership with himself gone from the tomb.
In a way, Ainz hopes to find a solution to tackle his issue with the Floor Guardians and the other NPCs of Nazarick through that experiment. Thus, Ainz had made it his plan that after he completes a certai
amount of work in the Sorcerer Kingdom, he will take both Aura and Mare to the Elf Country to make some friends there. Ainz once thought about this matter before, about whether or not he was pushing too much
work onto the elven twins and felt this was the only way to promote a healthy growth for them. Using a paid leave plan as an excuse and to set an example for the NPCs, Ainz reasonably plots to leave the
Sorcerer Kingdom in Nazarick's control (particularly Albedo) while he goes on vacation with Aura and Mare to the Elf Country.Overlord Volume 14 Chapter 4: Well-Prepared Traps
=== The Current Situation of Various People. A Prologue Arc ===
Ainz Ooal Gown having learned about Emperor Jircniv's stomach problem and him using the Ring of Unicorn sent the emperor a new magic ring as he believed using the Ring of Unicorn was a waste. The ring
Ainz sent was an item the undead found on the market with the purpose of surpessing stomach aches.The Current Situation of Various People. A Prologue
===The Half Elf God-kin Arc===
 and The Half Elf God-kin II Arc
Following the Sorcerer Kingdom's conquest of the Re-Estize Kingdom, Sorcerer King Ainz found himself swamped with more work. Though dreading the increased workload, Ainz was more disappointed his inability of convincing his subordinates to accept the vacation system. He mind then wandered to Aura and Mare, specifically in their natural development of making friends with other elves, which then turned his interest in the Elf Country. Believing he needed more information, he decided to head to the 6th Floor with his attending maid Lumière.
Once there Aura met to greet him. While on the floor, Ainz decided to take the opportunity to inspect the new areas, such as the Field of Flowers where Nazarick kept the new plant-type monsters. The Sorcerer King was guided there, where he was introduced to Violet, the Alraune Lord. Upon inspecting the area, he found that the changes to the once undeveloped location were satisfactory and asked Aura to take him to the elves he allowed to stay with her and Mare.
Brought to the Gigantic Tree, Ainz found Mare and the elves waiting for him. Needing a proper setting to conduct his conversation, Ainz selected the Canteen on the 9th Floor. Once they arrived, they were well received by the Homunculus Maids having lunch there, as well as Shihoutu Tokitu the Head Cook who tried to offered to cook a lavish feast and reserve the entire area for Ainz's use. Such arrangements were not necessary for Ainz as he only came to the Canteen to have a peaceful meeting with his guests and after some reproach adn convincing words managed to restrain Shihoutu to resume his duties and treat him as a normal customer.
Ainz then directed his attention to the elves before him, and began questioning them about their homeland. Under the peaceful setting, as well as the delicious drinks and food, the elves divulged some details that they knew about their country. And while the information was limited due to their status as village girls, Ainz learned about their daily lives in the forest and more important about the elves' unique magic called the elf trees. This magic seemed unique to Ainz as it never existed in YGGDRASIL and wanted to establish relations with the Elf Country to acquire it.
To reward them for the information, Ainz offered to return the elves back to their homeland, or someplace safe. The trio of elves were unwilling to speak of the matter, not with Aura and Mare around. Seeing this Ainz politely made an excuse for the twins to go from the table for more drinks. When that happened, the elves asked the Sorcerer King if it was possible to stay within Nazarick, as they had grown accustomed to the luxuries and enjoyed taking care of the twins. Their wish was granted, and Ainz asked them to provide him their knowledge of what they knew about dark elves, but sadly they knew very little as elves and dark elves normally did not interact.. 
After his meeting, Ainz made his decision and hatched a plan to go on a vacation to the Elf Country under guise of putting his nation through a practice drill in case he were to go missing. He informed Albedo of his plans and that he was bringing along the 6th Floor Guardians, Aura and Mare, hoping that interacting with other elves would help in the duo's development. Knowing that Elf Country was currently at war with the Slane Theocracy, not wanting to start another conflict so soon after the one with the Kingdom, the monarch altered his plans: if he could not bring the twins to the rest of their kind, he would bring the rest of their kind to the twins.Overlord Volume 15 Chapter 1: To Take a Paid Vacation
Ainz Ooal Gown, traveled to the Great Forest of Evasha under the pretense of taking a paid vacation with Aura, Mare and Fenn in tow. Once there, Ainz collected information of the Theocracy's invasion progress. From an aerial view he noted their advance to the capital involved building a road to cut through the forest. After several days of observing the military forces, Ainz decided to check on the royal elven capital at Crescent Lake.
At nightfall at the capital, still ever paranoid of meeting a powerful foe, he conducted his investigation under the utmost secrecy using invisibility and remote viewing magic to explore the city. His investigation went undetected, and somewhat fruitless as the entire city was chaotic and just a mass of thousands of interconnected elf trees. Ainz returned to his temporary base of Green Secret House in the forest where his party were waiting for him. 
After three days of eavesdropping on the elven citizens, Ainz finally caught as break when he located a home of an elf who lived alone. Using mental manipulation, Ainz acquired the elf's cooperation and made him tell the whereabouts of the dark elves. He attempted to learn as to why the Theocracy was invading the nation, but only found out that the elf was in the dark of the true reason. Having learned enough, the undead erased the elf's memories and returned him home. To make sure that the magic worked, Ainz while invisible, used a small idol of Tsungoga to hit the elf on the head to awaken him. Upon awakening the elf had no recollection of his meeting with Ainz, but believed that the blow to the head by the idol was a sign from the deity and thus began praying.
Ainz's party then set out to the dark elves, with Aura guiding them through the forest with Fenn acting as their mode of transportation. In an hour they managed to reach the Three Trees that marked the territory of the dark elves. But after some time, they were still unable to locate it, with Aura sensing they were close. To see if she could find the village on her own, Aura went out with Fenn to scout out the area. Whilst they were away, Ainz used Statue of Magical Beast - Cerberus to call upon a Cerberus to act as a guard for the camp while Fenn was away.
Aura and Fenn returned bringing a new guest, the Ankyloursus Lord one of the bosses of the forest. Ainz was surprised by the new acquisition and while originally wary of Aura of keeping the creature, he changed his mind around dinner, as he found that it could serve a purpose in a plan he had to make Aura and Mare friends with the dark elves.Overlord Volume 15 Chapter 2: The Travelling Scenery in Nazarick
The team then relocated more south of the area where the Ankyloursus Lord had made its territory where a large village of dark elves was located. Along the way the team met several strong monsters and other ankyloursi which Aura killed so that they could not interfere in Ainz's plan for the village. The bear monster was then let loose upon the village with strict orders not to harm the dark elves, but to attack the elf trees.
It stopped when Aura appeared and used her physical might to drive it off in a visible display. Thanks to that, her actions cemented her as a savior of the village creating the setting for the elves to be in debt to Aura and her associates. 
Aura's ascent as a hero in the village did not proceed as expected, due in part to Aura not understanding that the purpose was to make friends, and mistakenly thinking that Ainz wanted to bring the elves to the Sorcerer Kingdom to rule over them, but also the situation in the village.. 
Ainz observed the events unfold while invisible and learned only scant pieces of the elders from his eavesdropping. In that they used something similar to the Trail of the Fey, though was unsure what it meant or their concept of the Fey Blessing. When he heard that the elders intended to use Aura in their political scheme he almost regretted his plan but decided to carry on to see what will happen. 
As three days passed, Ainz was more disappointed in seeing Aura being treated as a hero, as he wanted her to act as a child with the other dark elven children. Because the village they were in was currently facing internal tension between factions over tradition and the young, Aura's age and ability lionized many members of the Youth Faction, like Plum Ganen, that called to cast aside the elders traditional values of the Council of Elders in favor of a system that recognized superior ability as qualities of leadership. 
When the time neared to meet the village, Ainz asked Mare to wear clothes more aligned with a boy in order to prevent the dark elf from being laughed at for his attire. He was surprised when his idea was accepted by Mare who understood that it was for the purpose of infiltration.Overlord Volume 15 Chapter 3: Aura's Hard Work
Some time since Aura ingratiated herself with the villagers, Ainz and Mare arrived. Under a magical disguise and the name Ain Bell Fior, the Overlord introduced himself as the uncle of Aura and Mare. Before the village he presented himself as a traveler and offered gifts in the form of various dwarven runecraft items. He briefly questioned by some of the villagers like Plum Ganen on whether he was a powerful ranger like Aura. He answered that he was a wizard, but the profession was unrecognizable to the dark elves due to their limited knowledge. 
The Overlord also met with Blueberry Egnia who he noticed was overly friendly with him, and asked he whether if Aura was betrothed to someone. The question while odd, caused Ain to assume that the dark elf ranger wanted to arrange a pairing with Aura and a child of his, unaware of Egnia harboring feelings for his young charge. When the Council of Elders made their approach to greet him, Ain believing he had a gist of dark elf vernacular attempted to greet them in such using improvised semantics and plant-based words. The reaction by his flowery introduction was profound to the elves, both the elders and even to the members of the Youth Faction. For both groups never had the need to practice etiquette nor did they know what the proper way city elves greeted each other. Believing Ain's greet was the formally way, and not wishing to show their ignorance for such customs opted to avoid interacting with Ain longer than necessary, essentially avoiding him. 
Their ignorance worked in Ainz's favor as it allowed him to move freely into the village without obstruction and to avoid having the villagers host a feast for him and his children, which would have caused them to suspect that something about their guest was off when he did not eat of drink. Ain proceeded to give Aura and Mare the opportunity to interact with the dark elf children, by bribing them with candy and having them play with the twins. Afterwards as part of his plan to learn all the secrets of the forest, Ain went to the home of the Chief Pharmacist Mango Gilena. When he attempted to initiate a conversation with the pharmacist, Ain found it difficult as the dark elf was uninterested in being social. Though AIn managed to pique the dark elf interest with his meager herbal knowledge, that he managed to parrot from his interactions with Nfirea Bareare. But it was the purple potion Ain had that caused Gilena to take the newcomer serious. Noting its value, Gilen wanted to acquire the potion. Through sly negotiation, Ain convinced the Chief Pharmacist to take him as a temporary apprentice for the week during his family's stay in the village which the dark elf consented.
During the seven days Ain enjoyed the training of his 'master' and managed to win the village's respect for him after he slayed a Giant Hypnotism Python. On the final day though a messenger from the elven royal capital arrived, ordering the village to send reinforcements to beleaguered city against the invasion by the humans. Due Ain's knowledge of the outside world, he was asked by the Council of Elders to act as an advisor during the meeting on what action the village and the other dark elf settlements should pursue. Though Ain did not want to get involved in a political mess, he still desired to acquire their knowledge of elf trees as well a herbal knowledge. While he preferred that they surrender to the Theocracy, he was unsure whether the humans would spare the dark elves. Knowing that he could not lead them out of the situation, he proposed that the dark elf villages each send a token force to defend the capital in order to fulfill their debt to their cousins, while still retaining enough warriors to ensure their safety. And while victory was unknown, he suggested that they make preparations to evacuate should the humans come for them. These suggestions were iterated as their choices that they could make. Having said his part, Ain informed the village that he and his family would be heading off to the next settlement. Though the news of the parting was saddening, Ain promised to see them again, and asked that if they did decide to leave that they bury a map of their current whereabouts so he could find them again. Just as Ain and the Floor Guardians were making preparations to depart, Gilen warned the family that several womenfolk of the village had taken it into their heads to join Ain. Realizing that this would be troublesome, Ain and the twins quickly left the village before his admirers could follow.Overlord Volume 16 Chapter 4: A Life in the Village
Ainz Ooal Gown and the twins returned to the vicinity of the elven capital where they saw that the Slane Theocracy's army sieging the city. For a week, the Overlord and the Floor Guardians saw that the human army were not using any area-of-effect attacks, nor summons or even proper siege weapons. From his point of view their campaign was wholly inefficient and wasteful of human lives. The group had no definite answers as why the Theocracy were letting themselves be so disadvantaged though Ainz hypothesized that the humans were doing so as an act of misinformation to misdirect the eyes of other nations who may be doing surveillance on their war. Ainz already wary of the Theocracy due to its long history considered striking an alliance with the Council State due to the latter's racial diversity, but decided to discuss the idea with Demiurge and Albedo.
When Aura suggested she infiltrate the enemy camp to gather intel, Ainz decided not to pursue the idea. To help the twins understand he gave a hypothetical question on if someone on par with Albedo would oppose Nazarick, would it be possible for them to steal all of their secret? The twins were initially confused at the question, thinking Ainz was accusing the Overseer Guardian of acting suspicious, but Ainz reiterated it was hypothetical. With more consideration the twins answered that with Albedo's skills she wouldn't be able to do so, as she specialized as a tank. While his example was poor it exemplified that Nazarick possessed multi-layered defenses, hence it should not be strange for other groups as well like the Theocracy, hence the need for caution. The very idea that other places like Nazarick could be on par sounded ridiculous to his companions, but it was a risk Ainz was not willing to discount. 
For their current mission, Ainz planned to commit a kill steal and plunder the elven capital of all its collection of rare magical items before the Theocracy could lay claim on them. His subordinates donned themselves in gear for infiltration while Ainz cast [Perfect Unknowable] on himself. Upon entering the castle, they planned to find a lone elf to hopefully interrogate to lead them to the treasury. When they got deeper into the complex they found a chamber with a carpet of dirt. They were soon met by the Elf King Decem Hougan who sensed and teleported to their presence. The Elf King seeing the intruders tried to intimidate them with his power, but it had no effect. The focus of the Elf King was on Aura and Mare, as he was unable to perceive Ainz through his high level invisibility. Since Ainz had told the dark elf twins to avoid instigating an attack, the Sorcerer King allowed things to proceed and observed the Elf King's interaction with his charges. His observation of the dialogue grew confused as to why the elf was claiming kinship to the Floor Guardians, insisting that they were his grandchildren. He entertained the idea that he could be perhaps an offspring of Akemi but reserved his judgment until more facts were known and resumed using his spells to try to gauge Decem's power. Once he had enough he then began to empower himself with various spells, however his calm process was interrupted when Decem declared that he would take the dark elf twins away, and intended to produce offspring with Aura. This infuriated Ainz causing him to physically punch Decem for his perversion, causing his invisibility to be undone resulting in a duel between the two kings. 
Ainz triumphed over Decem, through a mixture deception and skills. It ended in the complete shattering of both the Elf King's pride and Primal Earth Elemental. Rather than admit defeat, Decem finally experiencing dread and weakness fled for his life, and slipped away despite Ainz and Aura's efforts to stop him. While he felt it was a pity he could not finish Decem himself, he had Mare pursue him to capture him, whilst he and Aura saw to the plundering of the treasury.
At the treasury, Ainz found the booty in the chamber not as impressive, but still collect what items were deemed treasures by the elves. The forces of the Theocracy were close to breaking into the castle, leaving Ainz and Aura with minimal time to avoid detection. They regrouped with Mare using an Elemental Skull when the male dark elf reported that Decem was dead and had been assassinated by a strange woman. Mare had the unconscious interloper with him, and Ainz was shocked to hear Mare regarded her a strong and a threat. Ainz weighing either to collect the Elf King's body or learn about the unknown woman, opted to prioritize the latter and bring her to Nazarick for interrogation. Once back in Nazarick, he took Mare's warnings seriously about their new guest being strong and ordered Aura to stand guard with Mare as Neuronist prepared her for interrogation. Next he sent orders to have Pandora's Actor go the elven capital to retrieve the Elf King's body for its items.Overlord Volume 16 Chapter 5: Kill Steal
Later Neuronist's findings from their new prisoner proved to be very enlightening. So much so that Ainz summoned Albedo to report to him in the Frozen Prison immediately. When she arrived, Albedo seeing his rage, pleaded for forgiveness, but he quickly told her that it was not her he was furious at but what he learned. He revealed what he and Neuronist had discovered through their time with their prisoner, that she was from the Slane Theocracy and had information putting the Black Scripture at the Katze Plains when Shalltear was attacked. Now knowing who was responsible for hurting one of his own, Ainz gave out an order to halt all of Nazarick's operations and to make preparations for war against the Theocracy.Overlord Volume 16 Epilogue 
=== Mass for the Dead Arc===
Momonga having bid his friend Herohero farewell decided to remain within YGGDRASIL as the game was about to shutdown. Unexpectedly Momonga head to the Throne Room where the Throne of Kings and resigned himself as the last member of Ainz Ooal Gown. Unexpectedly the end did not happen. Momonga instead found himself to be in a ruined Great Tomb of Nazarick, as if someone had attacked and drove through Nazarick's defenses. Lacking answers Momonga found that all the NPCs in the dungeon were dead. Using his magic he revived the Pleiades who to his shock had become self-aware. Their self-awareness though shocking, Momonga concentrated on focusing on learning what had happened. The only clues to the attack seemed to be an odd Crack where the throne once stood. 
Before he could investigate further, an unknown homunculus appeared in the chamber. Thinking him to be an enemy, Momonga was prepared to kill him suspicious as how the person was still alive in the dungeon amongst all the destruction. But once one of the Pleiades maids recognized him as a creation of one of the Supreme Beings, the Overlord released his guard welcoming the protagonist as a fellow survivor. However they are interrupted when the Crack glows and releases strange monsters. Momonga's party are at a disadvantage as it is discovered that despite reviving the Pleiades, the incurred a severe level down, weakening their powers. The odds causes Momonga to call for a retreat, but the protagonist convices him that they can win and his confidence restore the Overlord's and the two succeed in slaying the monsters. Momonga then collects several strange crystals from the beasts before calling his subjects to prepare to retake the dungeon from the invaders.
Momonga then hastily revived Albedo, who he quickly informs of the status of Nazarick. The Overlord uses magic to summon undead warriors to purge all the monsters emerging from the Cracks found within the dungeon. To determine the status outside Nazarick, Momonga uses the Mirror of Remote Viewing and learns that tomb had been transported to another world. In a new world with unknown dangers, Momonga is convinced by the protagonist to allow him to explore beyond Nazarick to seek answers to where they are.Mass for the Dead Prologue
Before sending the protagonist off, Momonga assigns Narberal Gamma to accompany the homunculus and gives the NPCs a Redeem Slime to act as a magical communicator. Using his mirror, Momonga planned to transport the survey team to outskirts of a human village he saw. Unfortunately the magic is incomplete due to interference by the Cracks and the team is instead placed in a forest some distance from the target zone. Momonga is not made aware of the displacement until the survey team sends a [Message] using the slime which has been named Slimeko. By then Momonga had done a damage assessment of Nazarick, and from the protagonist learned of the chaotic situation of the outside world that was in turmoil due to the Cracks and the Chaos Beasts. All this serve to fuel Momonga's fear that an unknown entity is responsible for not just the attack on Nazarick but the new world as well. Momonga then orders the party to continue collecting information from the surviving humans at Carne Village. As the protagonist continued his collection and achieving many surprising things, his deeds cause Momonga to be continuously be surprised by his friends' creation.Mass for the Dead Chapter 01: World of Chaos
While surveying the damage of the dungeon, with Albedo and a revived Demiurge, Momonga assigns the Pleiades to conduct an investigation on the Cracks To compensate for their lost levels he has them train until he deems them strong enough to handle the danger. Once the maids collect enough information on the cycles the phenomena, Momonga sensing that Nazarick's survival depended on getting stronger initiated the Nazarick Revitalization Plan to not only rebuild the dungeon but enhance it strength and assets.Mass for the Dead Special Event: Nazarick Revitalization Plan -Start- 
Many of the Floor Guardians were suffering from a loss of levels, so Momonga began encouraging many of his subordinates to better themselves either through physical of mental means. For Aura he permitted the weaken beast tamer to renew her menagerie of pets by seeking wolves in the nearby Great Forest of Tob.Memory of Chaos: Aura Bella Fiora Others like Mare were asked to assist in disguising Nazarick from prying eyes and for his service the dark elf was awarded a Ring of Ainz Ooal Gown.Memory of Chaos: Mare Bello Fiore
When Narberal Gamma returned from the outside world to share what she learned, Momonga would witness that the maid began to infect the other maids on her bias attitude towards humans. Seeing that this needed to be remedied in a delicate manner as to not upset Narberal, Momonga permits Sebas Tian to handle situation.Memory of Chaos: Narberal Gamma Momonga would eventaully reel back to the idea that he was a leader now to beings that his friends created. Unsure of how to motivate them, the Overlord solicited the returned protagonist to conduct a survey on the needs and desires of the Floor Guardians.Memory of Chaos: Momonga
As he struggled to bring Nazarick to a sense of normalcy, Momonga had to contend with the antics of his more enthusiastic and repentant Floor Guardians. From Albedo who blames herself for failing to defend Nazarick as the last line of defense, Shalltear seeking to take the blame out of guilt for Nazarick's fall as the first line of defense, Demiurge seeking to replace the damaged Throne of Kings with the Throne of Death and Cocytus overtraining himself and members of the Pleiades to regain his former power. Through all this he manages to help Albedo regain her confidence and even accepts the creation of a new secret unit.Memory of Chaos: Albedo Shalltear's emotional conflict would also be resolved not by him by a reinvigorated Albedo after she shared words with him.Memory of Chaos: Shalltear Bloodfallen As for Demiurge, his action in creating a new throne was touching to Momonga, but truthfully he found the new throne to be disgusting. To avoid sitting on it the undead declared that he would not sit upon any throne unless Nazarick was fully restored to its former glory. Though he postponed the actual use of the chair, it emboden Demiurge to craft an even better one.Memory of Chaos: Demiurge For Cocytus he shifted the warrior's focus from achieving physical strength to that of enhancing his strategizing after demonstrating in a game that the former was not all there is to to achieve victory.Memory of Chaos: Cocytus
Momonga turned over all available assets to bring Nazarick back to its normal standards, even seeking the aid of Pandora's Actor, one of the only NPCs that were spared from being killed during Nazarick's initial transfer to the New World due to the Treasury's isolation from the rest of the dungeon. Though the NPC represented his dark past, the undead saw the value of the Area Guardian in acting as his body double and coached his creation in mimicking his behavior in emergency, and hopefully to erase his larger than life personality.Memory of Chaos: Pandora's Actor 
After being informed by the survey team that they made contact with the Sunlight Scripture and were about to conduct an expedition to the Tob Forests to learn of the source of the Chaos Beasts in the area, Momonga approved of. To support them he also sent Aura and Mare to serve as escorts.Mass for the Dead Chapter 02: Wise King of the Forest Momonga learns from Demiurge that the Cracks within Nazarick despite spewing noxious miasma has no harmful effects towards the dungeon's inhabitants an oddity as testimonies outside Nazarick claim that those who breath in the fumes are horribly mutated into Contaminated Beasts. Still Momonga feeling it is relevant, passes the information to the survey team led by the protagonist.Mass for the Dead Chapter 03: Fractured Forest Once Aura and Mare returned from the mission Momonga is given news that they recruited Hamsuke in Nazarick's ranks, which he approves given Nazarick's lack in manpower to dismiss potential assets.Memory of Chaos: Hamsuke
Several activities of the Pleiades are also noted by Momonga and their actions intrigue the player on the NPC limits and parameters. For instance Yuri Alpha taking the imitative to clean up the debris scattered around the dungeon and even destroy them for easy storage. Though Albedo was angered that Yuri destroy pieces of the dungeon to Momonga is represented a notion that the NPCs were able to find loopholes in their programming.Memory of Chaos: Yuri Alpha He though would see some like Lupusregina Beta slack off their duties on monitoring a Crack, which earn the maid a sever reprimand for her laxity. But he is again impressed by Lupusregina's drive to improve herself and her work ethic later.Memory of Chaos: Lupusregina Beta Their mental well being would has be taken into account, such as when CZ2128_Delta began showing signs of emotional distress not just from her revival but also when he accidentally volunteered to hunt humans for Demiurge's projects. To put her at ease, Momonga gifted her a baby Spear Needle.Memory_of_Chaos:_CZ2128_Delta
Other instances like with Solution Epsilon saw that the maid committed an act of what could be considered to be treason after the Pleiades member kidnapped, Miyoshi. Her actions caused Nazarick to go on high alert as it was believed that Miyohsi was taken by an intruder. Before things could spiral further out of control, Solution confessed to the crime to Momonga and Yuri in private as the kidnapping was furled by jealousy over Miyoshi's role as Momonga's bathing attendant. The incident which would be known as the "Miyoshi-kun's Disappearance Case" was then buried as the circumstances were considered embarrassing to be made public.Memory of Chaos: Solution Epsilon Momonga would later be the focus of a rivalry between CZ and Entoma to decide who was the elder sister between the two. The two maids tried to out do one another in hospitality, but when they failed they pleaded to Momonga to decide who was the elder sister. In the end Momonga stated that it didn't matter as their creators never intended to make one senior over the other. Though not expecting to hear that, his words calm the maids to give upn on their rivalry.Memory of Chaos: Entoma Vasilissa Zeta As Momonga continues to rule from a rebuilt Nazarick, he receives a report from the protagonist that the latter has chosen to become an adventurer to gather more valuable information on the New World.Memory of Chaos: Sebas Tian
To assist the protagonist in his exploits as an adventurer, Momonga had previously sent out Solution Epsilon and Sebas Tian out into the field to infiltrate E-Rantel. Solution under the alias of Soi the adventurer and Sebas Tian as Sebas the miner were to assist the protagonist and Slimeko once they entered the city.Mass for the Dead Chapter 04: Fortress City E-Rantel
His every action though was observed by the NPCs and at one time when he reminisced about wishing to see a cherry blossom viewing, Albedo took it upon Nazarick to help his achieve it. An expedition into the Great Forest of Tob was launched to acquire a special tree known as the "Legendary Tree". The act by which the NPCs were willing to please him touched the undead and allowed himself to enjoy the festivities after the tree was brought to the 6th Floor.Mass for the Dead Special Event: Supreme Hanami 
Momonga would also try to reward his subjects if they provided a unique service. Neuronist Painkill who had been recently revived only to feel obsolete due to the protagonist intel gathering, redeemed herself in Momonga's eye after she interrogated a knight that was sent by Marquis Pespea to scout the area for a cavalry run. Her report managed to save Nazarick from being exposed, and Momonga was about to permit her to kiss him, but her attempt was foiled by Albedo who imprisoned her for a random charge.Memory of Chaos: Neuronist Painkill
Nazarick's secrecy was of utmost important as he approved a proposal by Demiurge to disguise an abandoned mine into a dungeon, after the protagonist reported that the Re-Estize Kingdom were sending adventurers led by Blue Roses to reclaim it and restart ore operations. To preserve their claim on the mine and ores, Momonga gave the Floor Guardian resources to dissuade the humans that the mine was anything but viable for humans.Mass for the Dead Special Event: Blue Roses Subjugation Plan
More would be learned about the Crack in the Throne Room, especially when it was discovered that it connected to other worlds. A group of people emerged into Nazarick and initially attack Momonga's undead summons due one of their members bias against the undead. However it was eventually made clear that Momonga harbored not animosity towards them, as he was keenly interested that one of the members included a young man from Japan and a goddess. Rather than continue hostilities he offered them sanctuary in Nazarick until they could find a way to return to their world. In return the visitors would complete a series of tasks for Momonga as payment. The two groups interacted and even at time became friendly with each other, however when Momonga invited them a place in his organization, negotiations broke when the goddess insulted and challenged him. The visitors were clearly outmatched by the Overlord but before they were defeated, the visitors were given a window to escape when a colleague of the goddess manage to open a portal back to their world. Demiurge seeing that they were escaping offered to capture them, but was held back by Momonga who felt it was not necessary.Mass for the Dead Special Event: Bless Nazarick!
Momonga would also face drama within Nazarick, such the ongoing conflict between Albedo and Shalltear to make him decide who should be his Queen. Unbeknownst to him the two women roped the protagonist and Demiurge in organizing a contest to decide who the position should go to. When the were at a tie, the female Floor Guardian literally tried to beg him to decide. Momonga however left the decision ambiguous making the verdict unclear.Mass for the Dead Special Event: Queen War 
During an experiment to see if [Gate] magic would work, due to the magical interference by the Cracks in Nazarick, Momonga and Shalltear opened a portal to a remote island. Curious about the new location, which pointed to have signs of human life, Momonga sent out the protagonist, Slimeko and the Pleiades. To better prepare them for battle at the waterside he equipped the maids with swimsuits. When they returned they brought back several artifacts from a pirate ship that could be liquated to gold and add to their knowledge on the New World.Mass for the Dead Special Event: Ultimate Battle Swimsuit
Later due to growing concerns on how well prepared Nazarick was in case another Crack formed in the dungeon, Momonga organized a mock combat scenario at the Fake Nazarick and had the Floor Guardians fight against him as an enemy that was invading the dungeon. The Overlord managed to outthink the NPCs for a while but they gained the upper hand when they started coordinating. However when they faced him in battle, he was victorous and was about to claim that doll to signal his win, but it was switched out by Albedo with a fake and when the time limit ended, the Floor Guardians were declared the winners.Nazarick Revitalization Plan -Mock Battle-
After the mine which Nazarick claimed as their own was found to have another cavern filled with Prismatic Crystals Momonga authorized it to be explored and the native monsters to be purged. Once it was done, he named Abyss Demon as the Area Guardian of the new territory.Mass for the Dead Special Event: Treasure Mining Area Momonga would conduct more experiments like cultivating pumpkin seeds from outside Nazarick and on the 6th Floor. While the pumpkin crop grew successfully, they inadvertently turned into Pumpkin Monsters that began to wreck havoc in the dungeon. All of the pumpkins were culled and turned into Jack-o-Lanterns, though one managed to possess Foire and turn her against the NPCs, forcing Momonga and the others to restrain and remove the parasite. Once the chaos subsided, Momonga allowed Aura and Mare to enjoy a nice Halloween celebration.Mass for the Dead Special Event: Supreme Halloween
In another of Demiurge's experiments with the Crack, a new group of visitors arrive, this time being soldiers. Like with the previous group that came to Nazarick, Momonga negotiated a deal for the soldiers to help him eliminate the Chaos Beasts infesting the surface of Nazarick. He found himself strangely gregarious towards the commander of the soldiers, who he realized had the same ethics and attitude as a Japanese salaryman. Just when the soldiers completed their tasks and he was about to treat them to a feast, the soldiers vanished mysteriously presumably returning to their world.Mass for the Dead Special Event: White Sliver and the Undead King
Word would reach Momonga's ears from the protagonist that Caloric Stone was in the New World and the cause of why the Great Lake was warming up based on what the lizardmen told the undercover adventurer. Eager to obtain the valuable mineral the Overlord authorized the quest, even sending out Cocytus and Aura to assist. In the end it turned out not to be Caloric Stone but a new ore called Heatstone. Even so the mineral provided useful in complementing the baths at Spa Resort Nazarick which Momonga and his Floor Guardians enjoyed using after the baths were somewhat repaired.Mass for the Dead Special Event: Spa Resort Nazarick
After some success in using the Prismatic Crystals to regain the Floor Guardians lost levels, Momonga decided to organize the Nazarick Fighting Tournament to hasten the process. He also used his magic to summon the Corpse Guardian to serve as a worthy adversary and wild card in the competition.Mass for the Dead Special Event: Nazarick Fighting Tournament 
Many more events in Nazarick would be hosted, such as the Christmas party, after Albedo urged her master to have one in Nazarick. Momonga would enjoy the festivities that were prepared by his subordinates and the unwanted advances of Albedo in a Christmas Costume.Mass for the Dead Special Event: Nazarick x Christmas 
Another crisis would occur in Nazarick when a strange New Year's atmosphere began to permeate the dungeon and affect the NPCs. Momonga seeing that the mood was unusual sought to find the cause. Momonga called the protagonist's adventurer team and Shalltear to him as they were not affected by whatever spell was on Nazarick. The group tracked the source to Fake Nazarick where the area had been converted into a Chaos Zone containing a place called the Takemikazuchi Shrine. Hindering them were many NPCs from Nazarick that were under the influence of the enemy. Their journey led them to the replica of the Throne Room where Momonga and he party encountered Shiramochi-ō the White Mochi King, an entity from a world that laid beyond the Crack. Momonga and his cohorts defeated the boss and seemingly everything was restored to normal.Mass for the Dead Special Event: 2020 New Year – Advent of Shiramochi-ō 
In truth it did not, as the Whit Mochi King used the last of his power to restart time, creating an alternate timeline were he regressed into a small child on the eve of when Nazarick fell under his spell. Momonga would find himself repeating the same loop all over again with slight differences, such as being accompanied by an amnesiac Shiramochi-ō, named named Shiro. Together he repeated the same challenges and acquired artifacts belonging to a group called the Seven Lucky Gods. After all of them were acquired Shiro regained his memories of the previous timeline and ultimately had to fight against Momonga as per his mission. The King of New Year however could not fall through to be the enemy of Momonga and his allies as he grew close to them during their journey. After learning that Shiramochi-ō was a neglected creation of the gods, Momonga permitted the boy one last moment of fun with his new friends. Shiramochi-ō then allowed Momonga to kill him so as to lift the spell over Nazarick. WIth the spell broken, none of the NPCs save for Momonga's party recalled what happened. Momonga after retrieving a gold coin that was left behind by Shiramochi-ō, decided to keep his memory alive by storing it in the Treasury.Mass for the Dead Special Event: 2021 New Year – Rebirth of Shiramochi-ō
In another summoning experiment with the Crack on the Throne Room, a new group was pulled through the anomaly. In the confusion of the entry, Demiurge accidentally injured one members of the party. Before the situation got any worse Momonga apologized for his subordinate. Seeing as they were pulled in an unfamiliar world Momonga offered them sanctuary. He took an interest in the leader of the group, seeing as he was able to attract and enrage any magic beast due to his unique scent. As he observed him remotely, Momonga noticed that the young man was somewhat burden as if under duress. Concerned, Momonga confronted his guest in private about it, but was unable to confirm anything seeing as the other person was unable to clarify his condition to. Understanding that he wanted to keep it discreet, Momonga gave him a few words of encouragement to not give up to whatever was ailing him. Just as soon as he gave those words, all the visitors from the other world vanished.Mass for the Dead Special Event: Life in a Different World with the King of Immortals
Momonga would face the results of his indecision over the Queen War. After he stated that he was unable to make a decision, Shalltear Bloodfallen came to the outrageous conclusion that Momonga's rejection of them was but a test or a "Trial of Love" to see who deserved his love. The Overlord once again became a target of infatuation, but this time Shalltear played hard to get and ignored and took a disinterest in Momonga, even rearing her obessive necrophilia. Her lack of attention caused Momonga some concern, feeling he had insulted his subordinate. Momonga's concern translated to Shalltear as Momonga being successfully seduced. When the Floor Guardian finally had some private with Momonga, she declared her love to him, much to his confusion. Once Momonga learned the details of what happened from her cohorts, the protagonist and Slimeko, he unable and unwilling to admit they were wrong instead lied to trio that the "Trial of Love" was not passed so as not to destroy their image of him and their self-respect.Mass for the Dead Special Event: Bloody Love Maiden
At the time of the second summit for the Tripartite Alliance in E-Rantel, Momonga authorized the undercover adventurers in the city to infiltrate the venue and monitor the situation to gain insight on the movements of the three nations and their knowledge of the Cracks and Chaos Beasts.Mass for the Dead Chapter 07 Trilateral Talks To learn more on how to prevent Nazarick from succumbing to ruin, Momonga decided that he needed to journey to the Roble Holy Kingdom which was reported to have fallen in the Catastrophe. Despite the urging by his retainers that it would be wiser to remain at the tomb, Momonga convinced them that he needed to go as he was the only 100 level fighter in reserve that could face any danger in the wild. Accompanied by an entourage, Momonga surveyed the remains of the Great Wall and pieced the clues that the Chaos Beasts attacked the structure due to the large concentrations of prescenes there. While Evil Lord Wrath held back the Chaos Beasts with his demons and demi-human thalls, Momonga decided that they learned eough at the sight then used his Super-Tier Magic to summon Dark Young to annhilate the monsters. The expedition then turned to exploring what was left of Kalinsha where the members of Nazarick faced off against a Dragon Chaos Beast. After it was defeated a artifact was discovered and brought back to Nazraick for study.Mass for the Dead Special Event: Nazarick Revitalization Plan -Holy War-
More visitors would arrive in Nazarick after another experiment on the Crack. One of the visitors underwent a severe psychological change into a darker personality and refused to recognize her own allies. After she ewas driven off Momonga worked with the visitors to capture their lost comrade less she become a danger to the world. Momonga allowed the visitors full use of his facilities as he learned the only way to calm the girl who acted as a vessel for a Spirit was to date it. Upon learning about dating spirits and the unusual phenomena in their world, Momonga became a target for Albedo's affections when she took lessons from the visitors and stole his first kiss. During their stay, Momonga spoke with the leader of the group, learning much about her leadership abilities. To thank her he helped arranged a date with her love interest.Memory of Chaos: Kotori Itsuka
When one of the guests, a volatile spirit known as the "Worst Spirit" asked for an audience with him, Momonga sent Pandora's Actor in his place as it was too soon to strong a wild card. Unfortunately the ruse was seen through the ruse. Pandora's Actor having dropped his disguise was unexpectedly praised as being cool by the Worst Spirit to Momonga's embarrassment. To apologize for the deception Momonga acceded some information and concessions to his guest.Memory of Chaos: Kurumi Tokisaki At the time when Momonga proposed a solution to send the group back to their world, something had already beat him to it an pulled the otherworlders back to their original world.Mass for the Dead Special EVent: Date A Nazarick
Demiurge after experimenting with seeds from the Legendary Tree to created Enhanced Treants had the idea to use them to create a security net around Nazarick. However at most three treants could potentially link with each other. To centralize their control, a presence like the Legendary Tree would be needed. While the rare tree was slain by Cocytus in the acquisition, Demiurge believed that the tree they found was not the true Legendary Tree but a mere offspring. Momonga enticed by the idea approved of the demon's proposal to launch another mission to find the Parent Tree. Once it was found, and pacified the tree it was used in a Yozakura where Momonga was entertained by Demiurge and Sebas Tian in Chivalrous Costumes.Mass for the Dead Special Event: Command Tower of Loyalty
The Crack on the 10th Floor would release new visitors, a rugged man and a child, both which had become hostile upon seeing Momonga, Cocytus and Demiurge. The two Floor Guardians though were more than a match to the warrior who underwent a berserker state. However the pair were saved by a strange skeleton knight that appeared and took them back into the Crack. The Floor Guardians initially wanted to purse, but Momonga stopped them sensing the knight was a deadly enemy they did not want to make.Mass for the Dead Special Event: Death Ruler and Berserker
Momonga would have to endure another of Albedo's ploys of gaining his affection, when she became a temporary maid. Though wary of the idea, Momonga found that morale and efficiency was up. Albedo even helped to organize a drill simulating a scenario if the 9th Floor was infiltrated by enemies. Once the drill was successfully completed it was believed that no one could approach Momonga's chambers. However the entire drill and it implementation was a devious plan by Albedo to isolate Momonga so that she could have her master all to herself, due to her convoluted belief that she was completing the "Trial of Love". Momonga was nearly raped by the Overseer Guardian until Shalltear caught on what was happening and saved him. Afterwards Albedo was disciplined for a time in isolation.Mass for the Dead Special Event: Queen War -YBI Plan-
Momonga would contract a group of visitors from beyond the Crack in the 10th Floor to search for a gold vein that was supposedly located in the Azerlisia Mountains. At the same time he placed surveillance on the group to study their unusual magic. With their help, Nazarick acquired a new source of money for their operations and slayed a Fire Dragon that had claimed the vein. Once he paid them for their services, after which they departed using their own magic to open a portal to their own world.Mass for the Dead Special Event: Congratulations! Lina and Momonga!
News about possible players being in the New World would alert Momonga. Having been informed by the protagonist that a certain dwarf named Tsuibayaya may have a possible connection to beings from YGGDRASIL, the Overlord dispatched undercover adventurers and the Pleiades to the remote seaside village where the dwarf lived and unexpectedly meet up with Blue Roses. When more information is uncovered that the dwarf was researching swimsuits from the tales of Minotaur Sage Momonga allows the investigation to continue after the protagonist reports about the Legendary Mermaid. At the end of the mission, the results are met with approval by Momonga. He notes that his adventurers have strengthen their relationship with the unsuspecting adamantite adventurers of the Kingdom, established a cooperative understanding with Tsuibayaya to help craft new variations of swimwear to see if designs from YGGDRASIL could be improved and also located the dwelling of a powerful merman.Mass for the Dead Special Event: Sage's Swimsuit 
On another incident closer to Nazarick, a series of haunting began occurring in the Great Forest of Tob. Momonga after being informed was fascinated that a haunting was occurring in the vicinity and sanctioned the protagonist to capture the ghost for study. A sting operation was organized using an impromptu Harvest Festival in the ruins of Carne Village and unexpectedly Nazarick caught not a spirit but a fox-girl named Kyuko. Though there were some misunderstandings on both sides, Kyuko was given a choice to become Aura's subordinate, earning new servant for Nazarick.Mass for the Dead Special Event: Heteromorph Night Parade
More visitors from the Crack would emerge after another experiment done by Demiurge, this time composed of a hero and three goddesses. Unlike the previous groups that had visited Nazarick, the hero was paranoid to the extreme and did not trust Momonga. While Momonga makes the attempt for a peaceful cooperative alliance, he too feels wary of the hero given his unknown strength and the deities under his command. Still both parties are forced to work together when an entity known as the Grim Reaper that originated from the Crack began targeting the visitors. The attack by the Grim Reaper is launched outside of Nazraick and seems immune to any type of attack. Momonga watching from the confines of Nazarick urges the hero that they need to join forces to defeat the enemy. 
The hero strong headedly refuses and instead blasts Momonga own flaws suspecting his intelligent nature to be a farce. Likewise Momonga accurately deduces the hero's true nature as someone who is so scared not for himself but rather for others, hence his cautious bravdo. Momonga explains he could not care less for his circumstance of what made the hero as he is, but threatens to remove him himself if the hero continues to be a hinderance and put his 'children' in harms way. The transparency between the two eventually causes the hero to accept a temporary alliance and the two utilize a technique from the hero's world to obliterate the Grim Reaper. Though the technique nearly costs the hero his life, Momonga has many healers from Nazarick buff the hero to stay off death. The hero and the goddesses having finally found a rapport with the undead, are then contacted by their allies in the Divine Realm who manage to connect to the their location and safely return them to their realm.Mass for the Dead Special Event: Brave And Undead Are Too Careful
A new incident would be brought up by Solution while she was acting under her alias as Soi in the Black Market of E-Rantel. Spotting Sebas Tian exiting a brothel, Solution reported it to Momonga, suspecting that Sebas Tian was meeting with a contact and possibly selling Nazarick secrets to a third party. The news was disturbing and almost unbelievable, but given Sebas Tian made no such report on his activities, Momonga order that it needed to be thoroughly investigated. He contracted the other undercover operatives in E-Rantel to follow Sebas Tian to see who he was meeting and to determine if he indeed was a traitor. After more information was gather by the protagonist and the agents, it becomes apparent Sebas Tian's unusual activities had no nefarious intent, but in fact was a personal initiative of the butler to free a young woman named Tuare from her servitude at a brothel. 
The fact remained Sebas Tian deliberately withheld information, and was a grounds for punishment. However his independent investigation had unwittingly discovered a native New World demon named Isabella. The demon was captured and taken for interrogation as the information she could provide would be a great deal valuable. Momonga accompanied by Shalltear and Demiurge, initially present to apprehend the butler for his alleged crime, instead came to judge Sebas Tian's actions. In light of the benefit that Nazarick gained, Momonga believed some leniency was in order, but to see if Sebas Tian loyalty was to him, ordered the butler to kill Tuare. Once the butler reluctantly threw a killing blow at the girl, it was stoppped by Shalltear, under Momonga's orders as it was all a test for Sebas Tian. With that, the question of Sebas Tian's loyalty came to a close.Mass for the Dead Special Event: Steel Butler and the Darkness of the Black Market
During the situation where Gazef Stronoff had gone missing when he led an expedition to the Northern Cave, Momonga hoped that the protagonist would rescue the Warrior Captain as if Gazef Stronoff was lost then the power balance of the Tripartite Alliance would be upset and set back Nazraick's plans. Momonga would be pleased to see the protagonist return with Gazef Stronoff, despite the human turning into a Contaminated Beast it still preserved Nazarick' relationship with the Kingdom. Better yet a new species was brought back from the Chaos Zone which Momonga was eager to dissect for its secrets.Mass for the Dead Chapter 09: Evil Darkness 
The Great Tomb of Nazarick would be visited by more visitors from the Crack, led by an individual known as the "Shield Hero" who acted aggressively towards the undead for summoning them from the world against their will. TO make amends Momonga offered his sincerest apologies and provided the group lodgings within Nazraick for the time being. While the hero is hesitant to remain under Momonga's roof, the alternative would see him and his friends having their memories wiped if they left Nazarick and so he agrees to the terms. During the strangers stay in Nazarick. Momonga studied them using surveillance magic with Albedo and Demiurge, who are under the impression his apology was a lie to lower the human's guard. 
Word reaches Momonga that another group o strangers from the hero's world was in E-Rantel by the protagonist. Learning that they were seeking the Shield Hero, and also have some sort of vendetta against him, Momonga arranged the two parties to meet in the Amphitheater. The hero is initially outraged that Momonga invited his enemies to the place, though Momonga prevents things from going hostile he inquires the reason for the hostilities. Once Momonga makes that clear to his guest, he is told that the other group believe that killing the hero would avert a crisis from destroying their world. Though in doing so the Shield Hero's world would be destroyed instead. The mission of the other group seems to be a worthy one, though Momonga is curious as to why the Shielf Hero continues to fight against them as he has no attachment to the other world. The reason for the Shield Hero's continuing defiance against fate is simply he doesn't fight for his world but for the people he cares about. These words convince Momonga to put his trust in the hero and reveals that the group he brought to confront the hero's party were actually doppelgängers to test the hero's character.
Since the calamity was approaching Momonga's world, the Overlord put his faith in the hero in resolving the crisis. The Overlord permits the hero and his friends to defeat the boss responsible for the calamity and after they defeat it, they are targeted by the other visitors hoping to kill the Shield Hero in his weakened state. Momonga's agents though prevent them hostiles from doing so and they buy them time to allow the hero's party to escape through a space-time crack that would hopefully go back to their world. Once they crossed the threshold, Momonga permitted his agents to allow the other group to pursue the hero as he wanted their conflict to be take out of the equation in the New World.Mass for the Dead Special Event: Shield Hero And Nazarick
Just as the militaries of the three nations of the Tripartite Alliance gather in E-Rantel, Momonga held a meeting to discuss the actions of the protagonist and how they contributed to the Three Kingdoms Improvement Plan. Though the plan was stated to be his own design, Momonga in truth has no idea what the future holds and allows Demiurge to dictate his will which to his shock is conquest of the New World and using the Alliance as a stepping stone for the ideal to create a new nation. Playing along with the lie, Momonga permits Demiurge to proceed with the next phase of his "master plan". The demon through his machinations proceeds to release the Chaos Beasts trapped in the caverns of the Northern Cave. The horde of monster then head to the capital of the Alliance aiming to destroy every creature in their way. Momonga and his court watch the battle between the human armies and the Chaos Beasts. In one instance he sees the lengths of which Emperor Jircniv Rune Farlord El-Nix sacrifice his own workers to eliminate majority of the Chaos Beasts in a trap.Mass for the Dead Chapter 10: Crumbling Overture
While marking the progress of the repairs done to Spa Resort Nazarick, the are brings bitter memories to Solution Epsilon and once again makes a request to replace Miyoshi as Momonga's bathing attendant. Her request sets off interest from the other women in Nazarick who plead to be given the position. Faced with being inundated by the cries of the female NPCs, Momonga devises the Miyoshi Cup to decide who is worthy of the bathing attendant mantle. The competition acted as a way to cull the competition as well as select women needed to activate the Open Air Golem that needed to be disposed of hidden in the baths. Once the task was complete and the survivors named, Momonga acted as the last trial, defeating all of the participants and declaring that no victor for the Miyoshi Cup. Though to appease the women's disappointment, Momonga demonstrated Miyoshi's cleaning abilities which showed all gathered that the slime was capable and even superior to them in washing his body.Mass for the Dead Special Event: Miyoshi-kun Cup / Mixed Bathing Washing Party
Momonga after a briefing with his creation Pandora's Actor over the gold mining operation in the Azerlisia Mountains is later visited by Aura and Mare in Christmas Costumes who present him gifts. Their attire brings up the topic of Nazarick's Christmas party, piquing Pandora's Actor's interest who is sad to learn that he was not able to attend it. This prompts Momonga to host another Christmas party so that all in Nazraick could experience the holiday season. Just as the dungeon was getting ready to set up the festivities, Nazarick received an emergency call for help from Cocytus stationed at the Great Lake. The Floor Guardian reported than a freak cold wave was pushing down from the mountains and driving hordes of wild monsters towards the village of the lizardmen allies. Unwilling to allow their allies to perish, Momonga organizes an impromptu investigative team composed of members of the Pleiades and equip them with Christmas Costumes that will protect them from the cold. Momonga and the others in Nazarick would celebrate the return of the Pleiades on their successful mission and locating the source of the strange weather anomaly. At the party Momonga toasted to his loyal subjects for their hard work for Nazarick, before having to contend with the jealously of Shalltear when he was approached by Albedo in her Christmas Costume.Mass for the Dead Special Event: Lizard in Blizzard
A pleasant reunion would occur in another summoning experiment, bringing previous visitors back into Nazarick with some new faces. Though initially thinking that Demiurge was responsible, Momonga is disturbed when his allies tell him that they were pulled by something in the Crack. The Grim Reaper comes to mind and Momonga informs them of its existence. The enemy though appears to be a clone of the "Worst Spirit" who uses the latter's shadow to attack the group. While his guests get reunited with their friends in Nazarick, he received a warning from Cocytus from one of the new guests about an impeding future she experienced.Memory of Chaos: Yoshino Using her knowledge of the events that will happen, Momonga manages to prevent Nazarick and the city of E-Rantel's destruction by shifting the location outside of Nazraick and having the visitors confront the clone in the open. The clone is nearly subdued when it shifts into the Grim Reaper, forcing the opposing party to slay it. When the visitors return back to Nazarick, Momonga welcomes them back and praises them on their victory. The moment is short-lived when a disembodied voice calls out and transports the visitors from the dungeon and back to their original world.Mass for the Dead Special Event: Date A Nazarick II
Project Valentine would be initiated after Mare questions Momonga on the significance of Valentine's Day. Momonga planned to used the leftover Valentine Chocolate from the game to create confections suitable for diplomatic gifts. It later evolved into a cooking contest when Albedo and Shalltear got wind of the plan. Aura would also join for fun and her entry of Natural Forest Chocolate would be selected by Momonga due to it being simple and recognizable for foreign dignitaries.Mass for the Dead Special Event: Bittersweet Nazarick
Due to the protagonist's part in saving E-Rantel, the undercover adventurer had been promoted to a more administrative role for the capital of the Tripartite Alliance. In a meeting the homunculus brought up a concern over the mental health of the citizens of E-Rantel and of how Nazarick could ease the trauma from the Demon Emperor Jaldabaoth. After some ideas are thrown around, it was agreed than an idol would be used to unite the humans and give them something to hope. The idol plan was created and Demiurge was given permission by Momonga to create a trial run of the plan to uplift the moods of the Homunculus Maids as a test to see if the plan could be applied to humans. While the NPCs of Nazarick thought the plan had nefarious designs to control humanity, to Momonga it was merely a way to boost morale for their human allies and provide entertainment for the maid staff. Through his subordinates efforts it led to recruiting Aura and Shalltear to form LittleMass.Mass for the Dead Special Event: (Part 1) Underground-Tomb-IDOL P Momonga would continue to monitor the progress of the idol team and gather feedback from some maids. The success and positive reviews of the performances were more than he hope for and Momonga attended the last show. Though after the show he had to deal with Albedo insistence of being made an idol so as not to be upstaged by Shalltear.Mass for the Dead Special Event: (Part 2) Underground-Tomb-IDOL P
To move onto the next phase of the plan, Momonga approved that the idol plan be implemented unto the city of E-Rantel, though instead of idol girls, adventurers would be used to attract the hearts of the masses. In this plan, Shalltear and Kyuko adopted the covers of the foreign adventurers Shall and Ku. The two women would infiltrate E-Rantel under a exhibition tournament for adventurers organized by the protagonist under the grounds to improve morale for the city inhabitants and to break down the difference between the inner city and new residents.Mass for the Dead Special Event: (Part 1) Undercover AdventurerMass for the Dead Special Event: (Part 2) Undercover Adventurer
Momonga would receive a request from the protagonist for permission to take a request from Prince Zanac Valleon Igana Ryle Vaiself to investigate a string of disappearances in the territory of Marquis Blumrush. After the mission was over, Momonga was brief on the details and learned of how Narberal Gamma was vital in taking down the remnants of Zurrernorn that were sacrificing brides for their rituals. Though he was disappointed to learn little could be found about who was backing the cultists and the noble was just the middleman. His concerns grew when Demiurge reported that Neuronist could not find anything from the assassin that murdered the noble, making him realize whoever done it was highly cautious and experienced in this sort of thing.Mass for the Dead Special Event: Bride Who Hasn't Fallen In Love For A Long Time 
After Momonga sanctioned some tests on some new swimsuits provided by Tsuibayaya and compared them to those in the Treasury, Albedo and Shalltear get the idea that this is a hint to another "Trial of Love" for them. They managed to loop the protagonist, Slimeko and Demiurge into the collective delusion and pressure Momonga to host the first Nazarick Swimsuit Athletic Meet under the pretense of entertainment for the community in the dungeon. Seeing nothing wrong with it, Momonga gives his approval unaware that it is another battlefield for the lovesick Floor Guardians. When challenges end in a tie between Shalltear and Albedo Momonga learns that this is once again part of the "Trial of Love" business. Having no heart to correct them, he instead consoles them on their failure citing that they impressed him on their teamwork and dedication. However the praise only drives them into a hormonal fury and they cling to him forcing the Eight-Edge Assassins and remaining Floor Guardians to rescue their master. In the end the two women are placed in solitary confinement for their unacceptable behavior.Mass for the Dead Special Event: Queen War -Nazarick Swimsuit Athletic Meet-
Only a few days approach when the city of E-Rantel would be transferred to the newly recognized Sorcerer Kingdom as a gift of gratitude by the Kingdom of the protagonist's part in saving the Alliance from the tyranny of the Demon Emperor. To officially recognize the protagonist's achievements in lulling the human nations into a sense of security, making them easy to manipulate by Nazarick, Momonga allowed the homunculus to ask for any one wish to be granted. The wish that he receives is for the protagonist to remain outside of Nazarick. Albedo is the first to cry out treason, but Momonga cuts her off so as he can hear the diplomat's reason. There he learns that the protagonist wishes to be allowed to operate out in the field full-time as the homunculus's new duties as the new administrator of E-Rantel would take him away from Nazraick for the foreseeable future. Finding it reasonable Momonga approves the request. No sooner does he do so, Albedo volunteers herself to leave Nazarick to officiate the signing of the transfer rights, doing so by pressuring her liege that she was more suited due to her high standing as the Overseer Guardian.
Momonga also delves in trying to determine the secret behind the Cracks and what connection the odd creature from the Norther Cave has with the artifact from Kalinsha was. So far neither he nor Demiurge could find a connection, but believe that there must be. In a meeting at the Round Table, Momonga hears a report from Albedo on the signing of the treaty with the Kingdom and the Empire. When two members of the Pleiades also return from a survey of the Northern Cave, they come back without Shalltear who had left with them. Since Shalltear had left the cave earlier to return to Nazarick, she should have arrived sooner than the maids. Curious Momonga uses Mirror of Remote Viewing to scry her position, until the magic mirror shows him the interior of the Katze Plains. There Momonga is shocked to find Shalltear's escorts dead and the resembling a battlefield.Mass for the Dead Chapter 12: Leader of Mankind 
Once it was determined that Shalltear was intercepted at the Kazte Plains by an unknown enemy, Momonga hurried to the area with an escort to ascertain Shalltea's state. Shalltear was under magic influence, her mind under someone's control. Though given that she still remains in the area, Momonga believes that the spell was incomplete. The undead then attempted to use his Shooting Star to lift the enchantment. However the spell fails and Momonga orders a full retreat back to Nazarick. Once back at their base, Momonga goes into a rage that frightening is subordinates. The Overlord recomposes himself and explains that the spell failed because it was done by a World Item, a power that has been confirmed to exist in the New World. The implications are devastating to Momonga, and he goes to the Treasury to retrieve the World Items in storage to arm his precious "children". There at the Treasury he also dispatches Pandora's Actor to make preparations to move the treasure to the Throne Room to prepare for a resurrection. 
The Overlord gathers his court and informs the Floor Guardians the plan, he will battle Shalltear to kill her as it is the only way to release her from the mind control placed on her. This brings much objection from his subordinates as they feel to have their master battle against Shalltear is too risky. Should anything happen to him then Nazarick would lose all cohesion. Momonga states that they have no choice as the opponent is the strongest of all the Floor Guardians, and many of the other Guardians have yet to recover their levels. Momonga on the other hand is still maintains his 100 level status and has no wish for the children of his friends to kill one another. An alternative plan is proposed by the protagonist, who devises a strategy to involve a army of undead fight against Shalltear Bloodfallen under the command of the homunulus, Albedo and Mare. Once the vampire is weakened enough by the undead and Floor Guardians, Aura used her World Item of Depiction of Nature and Society to transport the turned Floor Guardian to another dimension where Momonga waited to land the final blow, thus providing minial danger to himself.
After Shalltear is slain with much regret by Momonga, the procedure to resurrect her are cast in the Throne Room. Shalltear is revived but unfortunately all her memories of the past few days are gone, and thus making the identities of her attackers a mystery. With this Momonga sees that Nazarick just nearly dodged a fatal blow and advises his followers to be vigilant as the enemy was still out there in the shadows. And personally vows to hunt the ones responsible for the dishonor done to Shalltear.Mass for the Dead Chapter 13: End of Date 
Days later, Momonga would learn from the protagonist that an adventurer heard about a massive undead subjugation was going to be conducted in the Katze Plains by the workers of the Empire led by Zero. Their target though was to locate and capture the Captain of the Ghost Ship. However the adventurer who told the protagonist this bit of information, had killed the captain before the workers launched their campaign. Suspicious of the workers heading out to the same area where Shalltear had been mind controlled, Momonga believed it to be related. But in order to determine if the Empire was involved in the incident, the workers needed to meet the elder lich of the plains. 
To give them a elder lich, Momonga used the dead body of an adventurer to create Iguva=41 to take them helm of the Ghost Ship. To ensure nothing went wrong, Lupusregina and CZ infiltrated the workers under the identities of Regi and Shizuni, acting as a pair of thieving workers. Zero and his remnants of Six Arms with the help of the two ladies managed to corner Iguva and defeated him. From his spies Momonga learned that Zero rather than wanting to kill the lich instead recruited him as a member of Six Arms as the undead's ability to subdue the undead in the plains were needed for a much bigger job.
It soon became obvious that the Empire's workers had nothing to do with the plot on Shalltear, instead Momonga's had stumbled onto a very different conspiracy. Rather than abandon the subterfuge in the Empire, Momonga ordered the Pleiades maids and lich to continue as he believed it was a rare opportunity to gain valuable intel on the Empire. He was proven right when the spies revealed that Zero was being hired by a group known as the Anti-Jircniv faction that aimed to overthrow Emperor Jircniv, deeming him to be weak after being defeated by Jaldabaoth. 
Their intent was to establish a smuggling route through the Katze Plains to the Theocracy to gain slaves and weapons to build an army. The prospect that the rebellious nobles taking over did not suit Nazarick, though Momonga hesitated from direct action as it was unclear if the emperor was manipulating from behind the scenes or was truly clueless of the fermenting rebellion. So Momonga ordered a "wait and see" policy to allow the events to develop before committing to any action. Later when Regi and Shizuni were recruited by Six Arms to join the team, Momonga staged events to give an opportunity for the two undercover workers to display their strength. He did this by having a Skeletal Dragon attack Six Arms while they were scouting out the route in the plains. 
And later when the Sunlight Scripture was sent to investigate the decrease in undead in the plains, unaware of the culling by the workers, Momonga ordered Iguva to send the Death Knight he assigned to him to attack the investigation party. This was to prevent the priests from learning of the smuggling operation and to stop them from becoming aware of the rebellious nobles plans. It worked and Momonga was able to view how the events played out. To his surprise he learned that the emperor was in the know on the rebellion against him and that Zero acted as the inside man to draw the nobles out and be arrested. 
It worked out in the end as the emperor got rid of the nobles and handed them to the Re-Estize Kingdom not only as a friendly gesture to it but also the Sorcerer Kingdom. Momonga was also pleased to hear that the enslavement of elves in the Empire would be reviewed in the aftermath, as the Imperial Army would free members with useful abilities and recruit them into their military forces. The Overlord got good public relations with the Empire, and also spies to monitor the situation. He also learned about the strange rune weapons that were said to have originated from the Dwarf Kingdom and soon became his next target of focus.Mass for the Dead Special Event: Worker Within The Fog
When trying to sneak into the library for more self-help books, Momonga came across Slimeko and the protagonist who asked him about some strange contents in a certain book. Momonga taking a look at a passage the was about invaders from the moon, deduced it was an unfinished novel by one of his former comrades. He told the pair who had written it and that it gave him an idea. To that end he organized a Tsukimi for the NPCs. to enjoy the view of the full moon outside the dungeon. However Albedo reported to him that the sun had returned despite it having already set. 
To solve what happened, the Overlord sent the returning protagonist and his team back to E-Rantel to gather information. After the protagonist got back to him, and told him about the strange behavior of Blue Roses, he was shocked when the homunculus believed that the events that took place during the fake sun was all part of the book Momonga looked at, under the misconception that it was a prophecy of the future. The reasoning of the protagonist of the series of mere coincidences related to the prophecy forces Momonga to give the adventurer full charge of the investigation as the protagonist was also under the impression Momonga was aware of the future events. To avoid being diminished he allowed things to play out though was worried what if the events came to light that he could not actually tell the future. In the end the protagonist with the help of Demiurge interpreted the prophecy in a way that suited them to make Momonga as awesome as possible, already knowing how everything would play out due to his intelligence. They found the culprits of the fake sun, a group of new heteromorphs with illusion abilities. Once they were brought back to Nazarick, the Tsukimi resumed and Momonga was once again seen as an all-seeing entity by his subordinated to his embarrassment.Mass for the Dead Special Event: Moon, Rabbit And Prophecy
Due to the good harvest of crops on the 6th Floor handled by Aura and Mare, Albedo managed to convince Momonga to re-open the idea of celebrating a Halloween Festival. While Momonga was unsure of the idea given the conflicts in the initial Halloween, he agreed to go through with it to boost morale. After it was announced that the festival will be held in Nazarick, Shalltear wanted to drop out of the festivities feeling she did not deserve to have fun due to her betrayal. To make her feel less guilty, Momonga blamed himself for the mind-control incident. Leaving the preparations with Albedo, Momonga was attended by the maid Foire who also had reservations of the holiday as she experienced some trauma by the rampaging Pumpkin Monsters at the time. Momonga help console her of the incident. The festival was arranged to be a defense training session to test the abilities of the NPCs. Though it was different from what Momonga had in mind, he permitted the exercise as it would be entertaining for him and the participants. From his office he and Demiurge, Lupusregina and Foire watched Albedo and Narberal play as evil witches who had invaded Nazarick while the Floor Guardians fought them. The event was pleasing to Momonga as it displayed new levels of improvement by the NPCs. Once the exercise was over, Momonga headed to the pumpkin field on the 6th Floor to congratulate the NPCs and enjoy the last hours of Halloween.Mass for the Dead Special Event: Witches' Costume Party 
In light of a successful harvest on the 6th Floor, Albedo managed to convince Momonga to re-open the idea of a formal Halloween Festival. Despite his reservations, given the previous incident with the Pumpkin Monsters the undead agreed to allow her to organize the event to boost morale. Momonga and Albedo would present the idea to the gathered NPCs, though Shalltear wished to decline from joining the festivities as she was still ashamed of being used by the enemy. To remove fault her part, Momonga put the blame on himself for not taking account of the possibility of World Items in the New World. He somewhat ameliorated Shalltear's attitude and then permitted the Halloween Festival to begin. Momonga observed the activities of the defense training part of the festival from his office, using the eyes of his Death Knight summon to witness how the attackers and defenders played their roles. Afterwards he joined the NPCs in the pumpkin patch on the 6th Floor to celebrate the rest of Halloween.Mass for the Dead Special Event: Witches' Costume Party
After another summoning experiment using the Crack on the Throne Room, Nazarick had three magical girls as guests. Momonga opened a peaceful dialogue with the trio and to his surprise went down with both parties trusting one another. The Overlord gained some useful information on the group's organization and technology in that they administered to dimensional travel. Though Albedo and Demiurge wanted to use the three as leverage, Momonga preferred to befriend the girls out of wariness that doing otherwise would make an enemy of this dimensional organization. When he was approached by the leader of the trio and hearing her heartfelt concern for the worsening situation of the Empire's territory being lost to the Chaos Beasts, Momonga permitted her and her friends to covertly hunt down the monsters. He ordered the protagonist's team to escort them and also take credit of the kills to bolster their reputation. Once contact was re-established back with the trio's organization, Momonga helped them create a plan to create a big enough disruption to clear the distortion waves around the New World to allow their dimension ship to transport the trio away.Mass for the Dead Special Event: Magical Girl and the King of Magic
Momonga would be informed of the status of the E-Rantel Magic Research Institute progress in finding a way to cure Gazef Stronoff and also Nfirea Bareare declining physical condition. For the latter he agreed to the protagonist taking initiative to address their lead researcher's health. In addition Momonga learned about the "Red Shadow" that was seen creeping at night in the city. Though the figure was vaguely similar to Santa Claus, Momonga did not think this was the case. But understood that the rumor needed to be investigated and dealt with. New of the epidemic spreading among the children were distressing to him as well, which his subordinates mistook for concern over losing potential thralls. After the source of the outbreak was pinpointed to be indirectly from a demon under Demiurge's command, Momonga ordered that they locate a way to cure the children with the Longevity Nut. After the protagonist's team returned, having successfully guided Nfirea into healing the children and solicting the aid of Evileye in the endeavor, Momonga welcomed his team back with a Christmas party and gave a toast to them in their honor.Mass for the Dead Special Event: E-Rantel's Santa Claus
During an end of year management report of the Treasury's contents from Pandora's Actor, Momonga was reminded that "New Year" was soon approaching. Reflecting that the event would bring a time where Nazarick would be under a mental control, Momonga intially sought to prevent it. To prepare Nazarick for an incursion he ordered everyone to conduct "general cleaning" of their floors. At the sae time he planted several Death Knights at crucial floors to serve as his eyes and ears. Whilst doing this he acted as a guide to the protagonist and Slimeko teaching them about the various floors. EVentually after a chance meeting with two maids who were caught eacting mochi and mistaken to be under the influence of the "New Year" and combined with Slimeko's musing of how much fun she had during the event, Momonga decided rather than prevent "New Year" it would be better to celebrate it. 
Albedo having been studying "New Year" suggested hosting a Kakushigei Tournament which Momonga consented. Momonga opened the event to all the NPCs. Once the tournament ended in a tie, it and the celebration ceremony inadvertently acted as a ritual that summoned everyone in the Amphitheater to the Bishamonten Shrine. To return home, Momonga led Aura, Mare and Shalltear to fight against a new incarnation of the White Mochi King. However the copy proved to be too strong for three Guardians. The members of Nazarick though were saved when an old friend Shiro came back having been ressurected thanks to the summoning. After defeating Shiro's alternate, Momonga formally introduced him to the rest of Nazarick and had him officially recognized as an ally and friend. Momong knew that he would have to eventually kill Shiro as it was the latter wish but took comfort that Shiro will not be effectively dead but return the following year. Momonga wanted to know more about Shiro's knowledge on the Sea of Possibilities and Seven Lucky Gods, and so to take the boy's mind off the inevitable death, Momonga celebrated the remaining hours of New Year with Shiro.Mass for the Dead Special Event: Counterattack Guardian Kakushigei Tournament
During a new summoning experiment, Momonga commented about wishing for their new guests to remain in Nazarick. This was overhead by Demiurge who took it as a directive to make the wish come true. The new guests composed of a Demon Lord and a giant spider were given the best hospitality by the NPCs. Momonga was unaware of his subordinates intentions, believing that they pushed aside their emotions of elitism to welcome outsiders out of their way. Momonga though was still wary of his guests, in particular with the Demon Lord as she was hiding her true strength. He used the opportunity to have a mock combatt battle against the guests with the Floor Guardians participating as well. 
The duel ended in a draw but the battle exceeded Momonga's expecations as it not only was exhilarting but provided the experience to his Guardians to hopefully help them improve in future battles. Momonga would eventually learn of the NPCs actions subtly convince the guests to remain in Nazarick, and not wishing to change the perception is was not his plab, decided to go through with it. So far only one fo the guests showed some willingness to stay in Nazarick when Momomga made the ofer. However before it could be truly considered, an unknown entity arrived in Nazarick. By stopping time, the entity expressed her intentions to return the guests back to their original world. Momonga who was using time countermeasures was immune to the temporal effect. Rather than fight against the retrieval of hsi guests, Momonga only asked to be allowed to say goodbeye to his guest. Afterwards Albedo and Demiurge lamented on their failure, while Momonga stated that their actions were true and should not be discouraged in the future, content that their guests left satisfied during their stay in his domain.Mass for the Dead Special Event: A Spider and an Undead, So What?
Momonga would receive a proposal drafted by Demiurge and Albedo which he approved after giving it a cursory glance. The proposal was a plan to organize a National Foundation Day Ceremony, to officiate the founding of the Sorcerer Kingdom. It would also serve a way to unify the newcomers and associates of Nazarick, as well as prepare the denizens of the dungeon a trial run of acting in a diplomatic setting. Although he could have cancelled the idea, Momonga decided to permit the event as it would be a good boost for morale. Unfortunately he knew nothing of diplomacy or etiquette and was hoping to observe some of the training sessions that the Floor Guardians would be attending to refine their mannerism and social skills. 
But he was asked by Demiurge not to attend, as it was deem not needed since Momonga was assumed to be a genius by the NPCs. Momonga in a difficult position to maintain his apearance as a brillant leader, and unable to acquire social mannerism teachings from the library without drawing suspicion, then came up with an alternative by seeking help from Pandora's Actor. However the Area Guardian had not knowledge of diplomatic skills whatsoever. Pandora's Actor seeing the frustration on his master's face then promised to attend the training sessions, which Momonga hoped that the Area Guardian would then share with him to prepare in time for the upcoming ceremony.Mass for the Dead Special Event: (Part 1) Nazarick Revitalization Plan -Anniversary- 
Through Pandora's Actor, Momonga was able to coach himself on the neccessary protocols for the ceremony. At the event, Momonga cemmorated the founding of his nation at Fake Nazarick and also addressed the visitors and allies of Nazarick that attended. When the event shifted to the banquet and dance portion, Momonga in a suit offered a dance with Albedo, exciting her beyond words. The end of the National Foundation Day Ceremony ended with the unveiling of the Sorcerer King Momonga Statue, which Momonga had to stomach praising despite finding it extremely flashy. A day later he held a meeting with his court to go over the success of the ceremony and social mannerisms by all participants. 
For the statue, Momonga decided to have the thing installed on the 7th Floor, to reward Demiurge's contributions. In a private meeting with Pandora's Actor he shared his experience of the ceremony. When asked a question bythe Area Guardian as why Momonga went through with the creation of the statue, despite his initial feelings towards it, Momonga did not give a truthful answer to Pandora's Actor. The real reason why he allowed Demiurge's pet project to become a reality was that its function served an essential placeholder for him in the event he ever leaves Nazarick. It was something he could relate to, given he did something similar when his guildmates retired from YGGDRASIL. Since the ceremony, Momonga rather than feeling cautious of the future, looked forward to what tomorrow would bring to him as King of the Sorcerer Kingdom.Mass for the Dead Special Event: (Part 2) Nazarick Revitalization Plan -Anniversary-
A report from the protagonist would inform Momonga of some concerns from the Sunlight Scripture that the "Dark Warrior" dolls from the Adventurer's Guild which based on the protagonist's persona was not only inducing hero worship, but dangerously into religious iconography. To prevent coming into conflict with the Theocracy over this, it was discussed that perhaps they needed to direct attention from the protagonist to a new character for the doll series. To test out whether adding a new character to the market would appeal to consumers, Momonga permitted that LittleMass be reactivated. For this Momonga wante dto use the idol group to see how a control group, being the general maids, would react when a new idol was brought on board. The new idol was decided to be Albedo and made a debut as "Neutrally" and LittleMass was reorganized as LittleMasStar. Momonga also acted as a participated in the idol campaign by acting as the final opponent to the idols alongside Sebas Tian and a Primal Fire Elemental he summoned.Mass for the Dead Special Event: Underground-Tomb-IDOL 2ndP
Momonga would have a pleasant visit from an associate from another world, who was re-summoned to the dungeon for a third time. This time bringing three new faces, Momonga once again allowed the humans sanctuary in his domain until they were returned home. From his guests Momonga learned about the time differential between their worlds, finding it curious and if the other worlds where their other guests came from also moved at different times. Though the guests' stay had weeks of peacefulness, trouble came up when his associate went on a flirtish spree with the women of Nazarick. It was then Momonga learned that his friend was suffering from an overload of energy that would normally be regulated in his original world. 
Basically having a walking bomb in Nazarick, keeping his associate with the dungeon was no longer an option. He had Lupusregina and Yuri allow said guest to escape and ordered the other guests and Pleiades to follow him to E-Rantel where the protagonist managed to broker a deal to have the guest return. In order to seal the excess power, dates with the members of the Pleiades was required or at the very least excite him enough to seal the condition. When the dates wee not enough, Momonga dispatched Pandora's Actor to take his form and fight the guest. The act succeeded allowing Momonga's friend to be unburdened by his power, though it was only temporary as the condition could resurface again. Momonga proposed that the guests remain outside of Nazarick in the meantime at least until they were returned home. Strangely enough the group ws returned home by an unknown entity. While Momonga was glad to see his friends were back in their original hole, he was disappointed that he was unable to say goodbye properly. By some sheer luck or design a [Message] was permitted to reach between barriers and connect him with his former guest.Mass for the Dead Special Event: Date A Nazarick III
Momonga, received an issue from the protagonist concerning illegal gambling in E-Rantel. Given that the homunculus had no actual experience with gambling, Momonga with the assistance of Demiurge, Pandora's Actor and Albedo helped construct Casino Resort Nazarick to serve as a test area for the activity. To study gambling psychology, Momonga invited the Floor Guardians and Pleaides to act as participants while assigning the roles of dealers to Narberal and Solution. To make them more at ease when playing the games such as roulette and baccarat, Momonga retired to his quarters to relax in a bath. Though he kept track of the NPCs progress. Once the experiment saw the potential for casinos being applied in E-Rantel, Momonga made a motion to draft a policy. Later to reward Narberal and Solution for their superb roles as dealers, he agreed to allow them to entertain him at the casino, with Albedo tagging along for her enjoyment.Mass for the Dead Special Event: Casino Resort Nazarick
The poor quality of fabric used in the production of "Dark Warrior" dolls for the idol project was brought to Momonga's attention. Since the dolls were vital in turning human hearts to align them with Nazarick's eventual plan for world conquest, a new substitute of fiber plants was needed. Momonga commissioned the protagonist and his team to do an investigation. And later was pressured by Albedo to allow her to join, after her argument that she was the original crafter of the dolls and should be the one to access the quality of the materials. 
Unknown to him Momonga played in her hand to allow Albedo not only to study the New World's fabrics but also to give her inspiration for a new wedding dress she was making to ignite his heart and choose her as his queen and bring the Queen War to a resolution. Once suitable replacement fibers were found, Momonga approved of the plan to create a local industry in E-Rantel to produce the fabric for the dolls. He was later entertained by Shalltear who was trying to flirt with him in his office, but they were interrupted by Albedo now decked in a wedding dress. The situation ended with both females fighting over Momonga for his attention, which restarted the Queen War, though the undead was saved by the Eight-Edge Assassins and had the two punished.Mass for the Dead Special Event: Bride Costume Is Self-Made
Momonga received a petition from Shalltear to resume conducting [Gate] experiments to repair the teleportation traps on her floor. Though Albedo and Dmeiurge believed that conducting teleportation magic experiments was a risk, Momonga ruled in Shalltear's favor as teleportation experiments were no less risky than the experiments with the Cracks that Demiurge conducted. Under the same conditions, Shalltear seemingly opened a [Gate] to the the beach of isolated island that was explored by the Pleiades many months ago. After conducting a few tests to confirm the stability of re-establishing a route to the island, it presented the Sorcerer Kingdom with some unique opportunities to expand its reach beyond the immediate area. 
While Momonga could not confirm the exact location of the island, the Sorcerer King and his advisors believed that the island could serve as a valuable marine resource. A plan was put in motion to have Aura and Mare scout the area with Entoma. Normally the same people who explored the island before would be sent but the Pleiades were occupied with other missions. To compensate for the dark elves' lack in aquatic combat, Momonga followed Cocytus's suggestion to have them train with the lizardmen given that the demi-humans lived in a waterside environment. For the twins' abscene he assigned Shalltear to guard the 6th Floor. After they returned they brought a request from Zaryusu Shasha who wished to join the expedition to the island. The request was accepted as Momonga believed it would give the lizardmen a stake in the acquisition of the island and prompt future collaborative projects.Mass for the Dead Special Event: (Part 1) Swimsuits, Lizards, and Dark Elves
When Zaryusu was brought from the Great Lake, the lizardman pointed out a blunder Momonga made when he forgot to give Slimeko and the protagonist their own swimsuits. However he was covered by his subordinates, misconstruing that it was intentional by Momonga to allow Zaryusu to provide positive input before the start of the mission, as they couldn't fathom he could make such a mistake. Momonga received updates on the island survey from Entoma Vasilissa Zeta and was happy to learn that the island was still uninhabited. Once the survey teach were just about done, Momonga came through the [Gate] to congratulate them for their hard work. B
efore addressing them he was distracted by Albedo in a revealing swimsuit but managed to stay focus on the matter at hand. One such item was to reward Zaryusu for his aid, who requested the fishing grounds of the island as a reward. The undead accepted the request as the lizardman promised that his people would help construct the base on the new territory as well as defend it. Since the island's location was still unknown, Momonga decided that the fog around it needed to be investigated in future mission. After some prompting from his subordinates and Cocytus's suggestion he began to permit regularly hosted Swimsuit Sports Festivals at the Great Lake.Mass for the Dead Special Event: (Part 2) Swimsuits, Lizards, and Dark Elves
During the time when the Great Tomb of Nazarick was transformed into Nazarick Academy, Momonga was the only person in the dungeon affected by the mental control. He saw that the entirety of Nazarick had their memories altered into believing that they were staff and students at a school. Though unaffected by the spell over his beloeved Nazraick, he found that everyone in the chanaged dungeon saw him as Principal Momonga. In order to solve the mystery of this new place, Momonga recalled Narberal and CZ who were in the field. To assist them in their investigation as students the Overlord gave them uniforms to blend in. While they collected information from their classmates, Momonga did his investigation in the staff room, where he found an inconsistency in the attendance logs. When he regrouped with his subordinates, him informed them that Shalltear's name was non-existent and he suspected that perhaps she was at the center of the incident.Mass for the Dead Special Event: (Part 1) Heart Pounding★Nazarick Academy
Momonga would bump into Shalltear on his way to observe a class. To utmost surprise she acted like she didn't know him and was condescending to the principal for making her late. Later it was revealed that Shalltear was a transfer student in Nazarick Academy, and sported a totally new personality. Momonga sensing something was amiss ordered Narberal and CZ to keep an eye on Shalltear. Momonga would dig deeper into the mystery of Nazarick Academy, having the distinct impression he heard it before. Looking in the library he found that several books were missing containing genres pertaining to schools and romance comedies, one in particular was title "Nazarick Academy" containing a story written by Peroroncino. Meeting Sebas Tian who was the school janitor, Momonga learned that he was support to teach a class, While he had no proper education, Momonga managed to teach a lesson on "information warfare" that engaged the students and even Shalltear. After school, Momonga acted as advisor to the Archery Club where he interest Shalltear in signing up. 
In a private meeting with his two maids, they tried to find a way to break the mental effect and transfiguration over Nazarick. Though going on past experience with the "New Year's Day" incidents, such a thing would require them to kill Shalltear. Momonga was apprehensive of taking this course of action as he already went through the experience of killing her and did not want to go through with it again. However it appeared that he did not have a choice when Shalltear approached him confessing her feelings. 
Due to Momonga not positively responding to the confession, Shalltear turned to attack him so no one could have him. Just when it seemed she would strike him and force Momonga to kill her, Shalltear's subconsious broke free from the mental control and realized she was being manipulated. Casting her role in the manifested space, Nazarick Academy vanish and was restored as the Great Tomb of Nazarick. Once the ordeal was over, Momonga did not think that Nazarick could ever prepare for another incident of that level. However the experience prompt Momonga to recreate Nazarick Academy as it was a unfulfilled wish of his comrade. Not only that the power of the Sea of Possibilities that led to manifest the unfinished work, gave him hope that he could perhaps use it to fulfill his dearest wish.Mass for the Dead Special Event: (Part 2) Heart Pounding★Nazarick Academy
At Albedo's suggestion, Momonga decided to make plans to personally visit the Area Guardians who were still maintaining their posts to boost morale. After the protagonist and Slimeko returned from the Adventurer's Guild, reporting that the guild was facing slander by the other guilds for it association with the Sorcerer Kingdom, accusing the Adventurer's Guild into a money-obsessed organization. To defuse the situation, Pluton Ainzach planned to display several relics belonging to adventurers that died in the line of duty. The adventurers that would receive such an honor were Igvarge and his team Kralgra. 
However their mithril plates were missing, luckily Momonga kept one of the plates as a souvenir, after he used Igvarge's body to create Iguva, though that still left three unaccounted for. Momonga realized it was a good time to out his plan he made with Albedo into action, and took, the undercover adventurers and Albedo to meet Nazarick's specialized survelliance magic caster, Nigredo. Momonga gave Nigredo the plate, which allowed the magic caster to use it as a medium to pinpoint the exact location o of the remaining mithril plates. Two of the plates were noted to be in the same location of where the adventurers were killed, but the third proved a bit troublesome as it was on a Skeletal Dragon in the Katze Plains. With Momonga's permission, the protagonist implemented a grand scheme to use the retrieval process to regain and strengthen the Adventurer's Guild with the Sorcerer Kingdom, manipulate New Six Arms into aiding Darkness into reclaiming the plates, and finally claiming a secure source of funds from both the workers and the guild to Ainz's delight.Mass for the Dead Special Event: Mithril Sleeping In Light Mist
Momonga oversaw another summoning experiment with Demiurge in order to study the Sea of Possibilities. Their summoning brought forth a single guest, which was odd as normally the summonings would bring more visitors. From their new guest they learned that his lover traveled with him through the Crack. Using his magic, saw that the visitor was incredibly powerful and to avoid conflict offered to make amends and help him locate his missing partner. He provided Aura and Mare to act as escorts, while having Narberal shadow them from the skies. In his discussions with Albedo and Demiurge, they noticed that the visitor seemed to be attracting a mass of Chaos Beasts which they believed was something more than coincidental. Later after word reached Albedo that their quarry was found in the lizardmen village, the information was passed to the field team who hurried to the Tob Forest. 
However they were met by a mass of Chaos Beasts that blocked their way. Through a direct [Message] with his guest, Momonga passed his impressions of the situation, hypothesizing that something was intentionally trying to keep the two lovers apart. His hypothesis turned to be truth as the leader of the Chaos Beasts was none other than visitor's father, who was supposedly killed. After studying the situation, Momonga determined that the entity was not the visitor's real father but actually just a figment created by the Sea of Possibilities from the subconscious fears of the visitor. 
The entity's plan was to kill the visitor's lover and throw him into despair, but was foiled thanks to Momonga. Since the visitor's lover helped to protect the lizardmen that were being besieged, by the Chaos Beasts from the forest, Momonga ordered Cocytus to protect her to repay the favor. To silence the manifestation, Momonga permitted his forces to work with the visitor to slay it. Once it was dead the Chaos Beasts vanished. The group then returned to Nazraick and allowed the lovers to have a respite. Over the course of time, Momonga learned that the couple were royals who would soon take the throne of their own kingdom. He expressed interest in forming official relations once travel between worlds was possible. By then a magic caster from the couple's world connected to brief portal to Nazarick to allow the couple to return home. Because the portal was only temporary, the couple had to hurry through it but not before saying goodbye to Momonga and his subordinates. After they left, Momonga was left wondering about the name of the land they hailed, "Britannia" when the protagonist arrived to report that he found references of the name in the library to his shock.Mass for the Dead Special Event: The Seven Deadly Sins and the Ruler of Death
Momonga received a proposal by the protagonist to host a Halloween theme festival for E-Rantel's Harvest Festival. It turns out the idea was 'his' as his musing on Halloween were misconstrued once again by his subjects who saw it as a way to deceive the world of the Sorcerer Kingdom's origins. Not only that it would lure other players in the area due to the allusions of Halloween. Unable to correct them and seeing logic in the scheme, Momonga approved the plan to create a false backstory of the Sorcerer Kingdom by associating his nation with the Boastful Sage. Later after its success, Momonga celebrated the victory with a Halloween Festival in Nazarick.Mass for the Dead Special Event: E-Rantel's Harvest Festival
In an effort to reinforce the idea that that the Sorcerer Kingdom was part of the legacy of the Boastful Sage, Momonga ordered Lupusregina and CZ to acquire samples of various magic items from Awrintar that were said to have been inspired by the minotaur hero. The purpose of the ideas was to give his subordinates ideas of new improved version, and thus were installed so that the entirety of Nazarick could test them and provide feedback as part of his "Daily Household Magic Item Plan".
Once all their feedback and ideas wee compiled into a document, it was dressed up under Momonga orders as an ancient manuscript and given to the protagonist who delivered it to Tsuibayaya. The dwarf's accepted the story that the schematics belonged the Boastful Sage and accepted the task, after the protagonist lent him Momonga's swimsuit to study. Later the finished items were presented at Spa Resort Nazarick, where many of the attendees wore swimsuits for the occasion, save for Momonga as he had given his to Tsuibayaya. There they showcased various magic items such as the Scented Moisture Fan, Heating Box, Cooling Device and Loudspeaker. And though many still needed improvement, Momonga was proud of the items and his subjects' hard work. To spread word of the Sorcerer Kingdom's superior quality magic items, Momonga allowed Lupusregina and CZ to take a prototype and leak the information to New Six Arms.Mass for the Dead Special Event: Charming Lie Inside The Invention 
Momonga was visited by Shiro, who had been staying on the 6th Floor since the last New Year's, during a general meeting with the Floor Guardians. He was warned by Shiro that New Year's Day was approaching and soon a mental spell engulfed all of Nazarick. The undead led those who were unaffected by the mental effect and those outside Nazarick at the time to lack a counterattack. Demiurge having deduced that in order to stop New Year's from overtaking Nazarick, the new White Mochi King needed to be defeated. In order to summon him, Momonga helped Shiro acquire the Seven Lucky God Key Items. Through the adventure, Momonga began to harbor worries about Shiro's growing power after one key item was found one by one. After the defeat of the boss of New Year's Day, Momonga secretly met with Demiurge and Mare to develop a countermeasure. Ultimately Momonga decided not to take aggressive action, but instead monitor and strengthen Shiro's belonging in Nazarick by giving him the special title of "New Year's Guardian".Mass for the Dead Special Event: Dyed White and New Year's Ruler
The protagonist would later bring word that the Sorcerer Kingdom's chocolate sales were dropping in E-Rantel. To amend this Momonga direct the homunculus to gather opinions from the people in E-Rantel on how to improve their product. The undead then later went to visit Pandora's Actor to do inventory of the chocolate supply. During a conversation with the Treasure, he realized he forgot to mention Valentine's Day to the Floor Guardians, and how it was associated with chocolate. Momonga didn't think much of the slip-up, but later when the opinions were collected, he found that the NPCs conducted their own independent research in preparation to develop a new chocolate product as they assumed his omittance of the holiday was a test. Momonga did not correct them as he wanted them to think independently. Later after tasks were assigned, he got a bit of a surprise from Albedo when she wore only a naked apron. After Golden Chocolate In A Bottle was made and released as the new chocolate product of the Sorcerer Kingdom, Momonga once again had to feign off Albedo's advances when she tried to smear herself with chocolate to seduce him.Mass for the Dead Special Event: Chocolate Is Colored With Gems
During a briefing on E-Rantel's recovery with the protagonist, Slimeko and his aides Demiurge and Albedo, Momonga was pleased with the overall productivity the idol plan and chocolate confectionary were having on the populace. What was satisfying to him was that the plans were bringing the puppetization of the Three Kingdom one step closer. At the meeting he requested a status update on Emperor Jircniv from his spies which he learned that the emperor was now totally under the Sorcerer Kingdom's thrall thanks to the protagonist. As always he reminded those in the meeting to avoid being negligent despite of the booming successes. 
After the incident involving remnants of Zurrernorn plotting to destroy E-Rantel came to an end, Momonga convened with his aides to discuss possible countermeasures and possibly eliminating the leaders of the cult. As always Momonga's role in the resolution was overblown by his subjects due to thinking highly of his peerless ability which Momonga reluctantly maintained. In addition to safeguarding E-Rantel, Momonga was interested to learn that swimsuits were gaining traction among the residents of the city, leading Demiurge to request to incorporate them into the idol plan.Mass for the Dead Special Event: Saints Who Dive In The Water
The demand for new chocolate items from the humans n E-Rantel was brought to the attention of Momonga by the protagonist. In consideration of who to assign, Cocytus boldly volunteered for the role. Momonga was taken aback by this, and even Albedo had doubts Cocytus could effectively produce a dish that would be enjoyed by humans give his tastes were of a different race. He was almost in agreement with his advisor, until he asked for a second opinion from Demiurge who actually advocated for the 5th Floor Guardian to be granted the opportunity to prove himself. 
In the end the Overlord granted Cocytus the task, and assigned Narberal to ack as his assistant. Even though he made the decision to put Cocytus in charge, Momonga was emotionally wreck of feeling insecure of his choice, worried he made the wrong one. In the end he all he to do was trust his subordinates. It paid off as Cocytus and Narberal were assisted by the rest of Nazarick, impressing Momonga on their independence and collaboration that produced the new item: Chilled Chocolate Confectionary.Mass for the Dead Special Event: A Sweet Plan
In another summoning experiment with the Crack, Momonga summoned a human and his pet bird to Nazarick. When the pair attempted to escape, Demiurge used his skill to force the human to submit, but Momonga noted that the bird was unaffected. He paid some mind that it was not an ordinary creature and guessed that it was the human's familiar and was impressed that he was unable to perceive their magical ability. Taking note of who their latest visitor was dressed and acted like a salaryman, Momonga deduced his origins to be from Japan. After the visitors and Momonga fought together against the Chaos Beasts, the undead negotiated with the human for the stay in Nazarick, and also to assist in locating their friend who may have been summoned to the New World.
Momonga eager to learn more about the human who turned about to be a peddler who frequented another world to sell his merchandise. From the goods present, Momonga was happy to see they included chocolates and paper which he bought in exchange for their meals. To provide their guests with a means of returning back to their world, Momonga allowed them to work for thei Chaos Stones needed to open a portal to their world. Along with Momonga attempting to learn how to cast the magic of the human and bird but was disappointed he was unable to due to the differences in magical laws.
Once their duo's friend was located in the Tob Forest and brought back to Nazarick, Momonga and his guests proceeded with the final negotiations of returning them home. It was here Momonga confirmed that while the human and bird were from Japan, they probably came from an alternate world. The negotiations included some memory alterations for the duo's friend so that she would not remember being summoned to the New World. Momonga was willing to indulge in assisting them, though noted that his involvement would expend a great amount of mana, but wanted an incentive such as the bird the human possessed. Though such a thought was rejected by the human who pleaded Momonga not to make him trade his friend. Instead an alternative offered by the bird, who would provide the magical energy needed for the memory wiping so Momonga could perform his spell. 
This alternative was satisfactory and Momonga completed the transaction before the visitors used the Chaos Stones with the Crack on the 10th Floor to open a portal back to their world. After they left, Demiurge and Mare was informed by their liege that he had withheld aggression towards the visitors, mostly out of wariness of the talking bird, who he noted was not only a shrew negotiator but terrifyingly powerful.Mass for the Dead Special Event: Sasaki, the Mage and the Undead King
Momonga while having a meeting with his retainers on the move forward with a sales plan for the inventions made in the Sorcerer Kingdom with the cooperation of the Adventurer's Guild was requested by Lupusregina to hear her out on an issue in the field. It concerned her wanting to learn the basics of money and transactions with humans while undercover. Since the NPCs lack as standard of knowledge on this topic, Momonga decided that it would be best to hold a money workshop to educate the field agents and Floor Guardians.
On who the lecturer would be at the workshop, the protagonist who was already occupied with his duties in E-Rantel, had a specific person in mind. Momonga was worried that he would be nominated, due to everyone's high expectation of his intelligence, but was somewhat relieved that Pandora's Actor was chosen instead. He then went to the Treasury with Albedo to ask for the Area Guardian's participation in the workshop. There at the Treasury, he encountered Yuri who was organizing the stored inventions there and passed on the details of the event, which she agreed to come to and would share it with Entoma.
Due to the large number of inventions stored with in the Treasury, starting to take up more space than expected, Momonga made a note to rethink the inventory, until the protagonist made arrangements for the goods to be stored in a warehouse in the city. He and Albedo entered the deepest most part of the Treasury to find Pandora's Actor busy creating a brand logo for the products. Pandora's Actor was willing to help in the workshop to explain the motivations behind money and human greed. Momonga also interested to see the contents of the lecture would also attend it.
At the time of the workshop, taking place in Casino Resort Nazarick, Momonga found it to be every informative that no supplementary details from himself was needed. Just as he was thanking Pandora's Actor and his collaborator Demiurge, he and the others attending the event witness Albedo and Shalltear appear in business suits. The two women added onto the lecture, by providing a professional outline on Nazarick's business internally and externally. In addition to a summary on its defenses and countermeasures put in place. He was greatly impressed how the two were able to use comparisons of the NPCs roles in Nazarick to that of humans in a company, allowing them to critically think for themselves. At the end of it, Momonga expressed pride in that the NPCs gained a deeper understanding through the study session. And hoped they will use the knowledge they gained to help them in their future work.
An emergency summons to all the Floor Guardians was held in Nazarick. Momonga was informed by the protagonist in E-Rantel that the storage area in the city, which was located near the Sewage Treatment Plant, had been broken into by slimes. While the inventions that were taken there were unharmed, the slimes had devoured all the luxury chocolates the Sorcerer Kingdom was holding onto to send to a noble for his party he was hosting. With the chocolates gone, the Sorcerer Kingdom was on the verge of losing face. Momonga demanded that they needed to act in order to correct this situation.
He witnessed Albedo taking command of the situation to coordinate a plan to create a new batch of chocolates to replace the ones lost. By giving out tasks to her colleagues to secure ingredients, transport and bolstering the defense of each floor in the absence of the Floor Guardians who were busy with their tasks. Momonga with Entoma coordinated with the ones withing Nazarick, relaying communications. In the end they successfully turn it into a positive situation for the Sorcerer Kingdom. Momonga called it a great achievement by everyone in Nazarick and was thankful for the stroke of luck that the workshop was useful in the crisis. 
Though Momonga had to face the personal challenge of being pestered by Albedo and Shalltear, asking if he admired them in their business suits. And later on he saw more NPCs wearing business suits, all them emulating the two Floor Guardians. Momonga was reminded of his time as a corporate slave, and felt sick to his non-existent stomach, as he saw it to a prelude of a "ban on reforms" being issued.Mass for the Dead Special Event: Work Style Reform in a Suit
At one point a proposal was brought before Momonga about creating an orphanage sponsored by the Sorcerer Kingdom. While Albedo disagreed with the proposal, Momonga saw the benefits of the institution and allowed the protagonist to present it to the city officials in E-Rantel. Unfortunately the plan was shelved after meeting resistance from the Nobility Faction.
Sometime afterwards, Momonga received a report from the homunculus on the disappearances of children in E-Rantel. The diplomat wanted to use the disappearances of the children to revive the orphanage idea, by proving that those who obstructed were involved in the kidnappings. Momonga while seeing the orphanage project not really a high priority for Nazarick, admitted that he had no way to see how the future will turn out agreed that they should not put it on hold and gave the protagonist his consent to solve the incident. He also recommended he speak with Pestonya given her concern for children. By the end of the case, Momonga received a full report of the perpetrators being arrested and the orphanage on its way to being established.Mass for the Dead Special Event: Prayers for Mother's Day
Momonga received an appeal from the protagonist to address the overworked staff at the E-Rantel Magic Research Institute. He personally felt that the researchers were too much like the NPCs in Nazarick, putting their work before their health. Though was appalled to hear that many of the Floor Guardians admired the humans for their commitment to their research. However they thankfully agreed to his creed of taking breaks. To alleviate the burden on the researchers, Momonga permitted the protagonist and Slimeko to act as the staff's assistants.
While in discussion on plans, Momonga was alerted by Entoma that there was something strange going on at the Great Lake. To investigate, Momonga sent Lupusregina and CZ to make a detour there when return to Arwintar. Shortly later on, they informed their master that something big was living in the lake. Momonga hearing the report, suspected that a giant slime may have taken residence in the Great Lake. He hastily put forth a second investigation team, which included the adventurer team of Darkness, and also Sophie Noia, mainly due to the human's specialty in slimes. Momonga was unsure of the human's discretion to the operations of the Sorcerer Kingdom, but trusted the protagonist to handle the task.
At the conclusion of the investigation, Momonga heard from his agents that it was indeed a giant slime, that had mutated after eating a Longevity Nut and driven to the lake by a Contaminated Beast. The undead was happy that the incident was resolved, and decided that it opened his eyes to the hole in his security net over the Tob Forest, which he decided to correct by sending more summons to monitor the area. To reward Sophie, Momonga allowed the researcher to keep the swimsuit she was given for the investigation, glad that the woman had enjoyed herself and gotten some needed rest from the experience.Mass for the Dead Special Event: In Search of My Own Resort
Momonga was informed the difficulties the protagonist was having in deciphering several confiscated secret letters their spies intercepted. Because of this the Overlord permitted his servant to utilize the books in Ashurbanipal. He then went invisible to the library and to his interest saw that Shalltear was there with the protagonist and Slimeko. Momonga eavesdropped on their conversation, hearing that they were attempting to open a book that belonged to Peroroncino.
At first not thinking much of the item, he realized that it the said book was involved in an incident in the past involving its creator being obsessed with a certain eroge game which frustrated his sister, Bukubukuchagama. He thought that the book may contained some secret data of his former guildmate, though did not consider it would be that significant. Later on the NPCs approached him to inform him about the book, and from his slip of words of being aware of their cooperation, cause them to mistake Momonga had anticipated the discovery of the book.
The book is finally opened revealing it to be an art book and containing a map to a cache of swimsuits. One being named for the Beach's Most Beautiful Girl Swimsuit. Momonga recognized the items to be part of Peroroncino's past fetish. And while the NPCs having tested them believed them to be treasured relics meant to be entrusted to Shalltear, Momonga suspected that his friend had intentionally hidden the ideas out of embarrassment. But with this truth in mind, Momonga decided to keep the knowledge to himself to maintain the illustrious origins of the treasure.Mass for the Dead Special Event: Unopened Book and the Supreme Treasure 
To punish Shalltear for being used by the enemy, Momonga sentenced her to be his chair, though the punishment seemed more like a reward to the vampire. In a meeting with the Floor Guardians and the protagonist, Momonga listened to the discussion of how there was no progress being made on identifying who attacked Shalltear. The meeting turned to concentrating on another issue, by the protagonist, the original crisis that they faced since the came to the New World, the World Incident and the Cracks. Since the issue on how it started is still a mystery was unresolved, the homunculus proposed that they seek answers from the older races that inhabited the Azerlisia Mountains. To this end the protagonist suggested that the Sorcerer Kingdom send a delegation to the Dwarf Kingdom as a cover to go to the mountain range not just to acquire weapons for E-Rantel from the dwarves but also information. 
The idea was approved by Momonga and he ordered the protagonist to lead the expedition. Opening ties with the Dwarf Kingdom proved to be a good investment as not only did the Sorcerer Kingdom secure weapons but learned from a Frost Dragon that prior to the start of the Incident, an old dragon had already sensed the coming danger and tried to recruit the latter's father to stop it from happening. Momonga was interested to know who the dragon in question was and planned to make adjustments to his future policies.Mass for the Dead Chapter 14: Mountain Range Lord
News that E-Rantel had been cut off by magical communication would reach Momonga due to the Shadow Demons stationed around the city. When Momonga was informed by Demiurge on the situation, particularly that the city was being invaded by Chaos Beasts formed from numerous Cracks within the city, Momonga feared that it may be the work of the entity responsible for the Catastrophe and the one who brought ruin to Nazarick. He immediately ordered Demiurge to put Nazarick on full alert. For the first time since he came to the New World, Momonga felt fear for the first time. More dire news came to Momonga when Demiurge reported that one of their people may have disappeared, Momonga hurried to the Throne Room to check on the statuses of the NPCs on the console.Mass for the Dead Chapter 15: Crackling World
Momonga learned from the status of the NPCs in E-Rantel, that while reports from the summons stated that they vanished, he was able to determine from the dungeon control systems that the NPCs were still alive. Months had passed since the attack on the city, and no word from the missing came to light. In the time that they were gone, Momonga had several Greater Doppelgängers assume the roles of Darkness in order to proceed with the Three Kingdom Puppetization Plan. The imposters were able to garner enough of the support from the survivors of the attack to start the reconstruction of the city and also see to the dispersal of the populace to other areas of the Kingdom and Empire. Momonga noted that the Tripartite Alliance had evolved into the Quadripartite Alliance, due to the greater influence of the Sorcerer Kingdom. Despite the gains, Momonga heart still ached at the uncertain fates of his subordinates. 
One of the doppelgängers who posed as the protagonist approached him for further orders on how to proceed when humans in E-Rantel wanted to host another "Greetings and Victory" Festival aka Halloween Festival. Given their reasons for asking the Sorcerer Kingdom, to promote morale in the recovering city Momonga agreed that the festival could be hosted. To him it was a good opportunity to spread the influence of his nation since the Theocracy had temporarily pulled out of the city. Later when Shall and Ku's presence at the festival was requested, Momonga was wary to allow Shalltear out in the field, due to the unknown identities of her attackers who brainwashed her. But consented that they needed to take the risk. Later after the festival, Momonga was relieved to hear that the event went without any interruptions, but now suspected that the Theocracy could be the culprits of Shallltear's brainwashing.Mass for the Dead Special Event: E-Rantel In Disguise
Day later, Momonga received word from his Greater Doppelgänger posing as the protagonist and Slimeko that they received a letter from Emperor Jircniv proposing to hist the "Greetings and Victory" Festival in Arwintar. While the festival was suppose to serve Nazarick's objectives, given that the human emperor wanted to brighten the mood of his citizens, the interests of the Sorcerer Kingdom aligned with the Empire's. Although Momonga agreed to the idea, he suspected that Jircniv's promoted the idea due to his obsession for the protagonist's approval.
Not too long Momonga gave his approval for the festival, Lupusregina returned to Nazarick to inform her master of Arwintar preparing for the festivities. And that the Empire had hired New Six Arms to provide security to the event. Upon learning of Jircniv's action, Momonga's advisors predicted that the added security was to handle the Anti-Imperial Faction that would try and cause trouble. This brought up one of the protagonist's last projects he did before he vanished. A series of secret letters that he decoded from one of the anti-imperial sub factions. While Momonga had long forgotten about the issue, he managed to convey a convincing deep wisdom of how to find the dissidents using the quote of "To hide the leaves, go into the forest." In any case he gave Lupusregina assistance in the form of Sebas and Narberal to help shadow New Six Arms to eliminate the anti-imperials to prevent them from foiling the festival.
Later after the festival and the anti-imperial plot to assassinate Jircniv was foiled, Nazarick's investigation pointed that the anti-imperials were being supported indirectly by the Theocracy via the Temples. When Demiurge suspected that the Deputy Pontifex Maximus was responsible, Momonga could not fathom on what the priest was thinking. For now the Overlord decided to keep a vigilant watch on the human and his actions. 
That being said, Momonga and Albedo informed Lupusregina of some wonderful news, in that that protagonist was alive and had returned. Not only that the missing Pleiades were possibly still alive as well. Momonga had ordered Demiurge to make preparations to launch a rescue mission, promising Lupusregina and the other Pleiades that they would have a chance to save their siblings.Mass for the Dead Special Event: The Glorious Imperial Capital Harvest Festival 
Going back to the news of the missing NPCs whereabouts finally arrived to Nazarick, when the protagonist returned. He was brought before Momonga, Albedo, Demiurge and Narberal for a debriefing. However before he could proceed, the protagonist requested a private meeting with Momonga as he had information for his ears only. Even though the homunculus was thoroughly checked for any deception, the members of the meeting were cautious of letting such a thing happen, as they feared the protagonist could still be under the influence of an outside party. Momonga sensing whatever the protagonist wished to keep secret was of the most importance, permitted the meeting. From what he learned from the protagonist, it was indeed earth-shaking so much so even the Overlord could hardly believe it and agreed such knowledge could tear the foundations of Nazarick. The information was kept strictly between master and servant, and the protagonist then shared what had happened to him and the other NPCs in E-Rantel.
It was then revealed that the NPCs were taken to the "other side" of the Crack. There under the influence of the "chaos environment" most beings were left comatose. Strangely the protagonist was unaffected by the transfer and neither was Gazeff Stronoff, who was immune due his affliction of the miasma. With the help of the Warrior Captain, the protagonist escaped back into the New World, where he found that months had passed as opposed to a day in the "other side". Once the details of the "other side" were clear, Momonga ordered Demiurge to create a countermeasure in order for a rescue mission to be possible. 
After a month of preparation, the equipment for the protagonist and the remaining Pleiades was ready. Before seeing them off, Momonga reminded them to prioritize the retrieval of their comrades and to escape should they encounter any powerful enemies.Mass for the Dead Chapter 16: Name of God
Momonga and the others waited in anticipation for news of the rescue. In a meeting with Albedo, Demiurge and Shalltear, Momonga decided to distract them from the rescue with a story of his past when he and his friends: Peroroncino, Bukubukuchagama and Herohero went on an adventure to conquer a dungeon. The story had an impression with Shalltear who wanted to train for the future when she went undercover as Shall. To do this she requested to have a mock duel with the dark elf twins, which the Overlord allowed. 
Seeing that this was a good distraction from the uncertain results of the rescue mission to the Chaos Zone, Momonga recruited Cocytus to duel Shalltear and the dark elves. Momonga timed the duel using Bukubukuchagama's wristwatch. Though there was no conclusive victor, the fight was enjoyable, taking him back to past. He acknowledge that the future may need the adventurer Shall to take the spotlight which excited Shalltear. 
Momonga received news that the protagonist successfully rescued the Pleiades and Slimeko from the Chaos Zone. But also on the communique he gets some troubling news. However he keeps this to himself until the Pleiades return to the dungeon. But one of his orders is for the protagonist to remain in E-Rantel. To keep up the celebratory mood, Momonga decides to host a banquet to welcome the Pleiades. During the banquet's preparation Momonga took the moment to thank Aura and Mare for assisting in Shalltear's training, tellling this with sincere words that they reminded him so much of Peroroncino and Bukubukuchagama.
Eventually the arrival of the Pleiades was announced by Shalltear, leading to Momonga and the twins to greet them in person. Before they met with anyone else, he moved to them Round Table Room and the maids as they wanted to tell him something before the dinner party. The report that was brought there was a surprise to everyone.Mass for the Dead Special Event: Two Shields That Will Never Fade 
Later its revealed that what he and the protagonist discussed with each other in private was that the protagonist was not an NPC of Nazarick. After being one the "other side" of the Crack the protagonist gained an epiphany that he was a creation of the Sea of Possibilities, who's memory was inserted into all the denizens of Nazarick to infiltrate it. Not only that Momonga was the only being in Nazarick who was unaffected by the mental manipulation, possibly due to being a player, and only came to regard the protagonist as a member of Nazarick due to the other NPCs confirming the protagonist's existence was part of the dungeon. The revelations of this were kept to the two of them as it could undermine the trust of the NPCs, and at the time Momonga still regarded the homunculus as an ally due to his many deeds. 
Though the truth was revealed to the entirety of Nazarick, when the members of the Pleiades and Slimeko returned from their expedition of the "other side". They informed Momonga and the Floor Guardians of a conversation they overhead between the protagonist and Enhela Read Gahi who was also a creation of the Sea of Possibilities and regarded the homunculus agent as a comrade with a shared purpose. 
But it was the name of the master who Enhela and supposedly the protagonist swore allegiance too that caught Momonga's interest: the Devourer of the Nine Worlds. Having heard of the World Enemy from YGGDRASIL, Momonga became emotionally shaken as the entity was a powerful being and the though of it being in the New World lessened Nazarick's survival. Momonga conversing with his aides deduced that perhaps the woes Nazarick suffered may have stemmed from the protagonist though it was too early too tell. But it was evident that the homunculus could not be allowed to remain in Nazarick nor could be let loose or he would spill their secrets. 
For now Momonga decided to permit the protagonist to remain at his post in E-Rantel and be kept on observation. And due to Enhela now targeting the protagonist, Momonga assigned Sebas Tian to act as his escort. A plan to use the protagonist as bait was proposed in order to capture Enhela and finally get to the bottom of the Calamity. After Momonga approved of the plans, he still having some sympathy for the protagonist, questioned the other Floor Guardians on their reaction to the protagonist and his origins. Like himself he found that they were also conflicted due to weighing friendship and duty.
Later while preparations of the operations were underway, Momonga made the arrangements to welcome Princess Renner as a full fledge member of the Great Tomb of Nazarick at the encouragement of Albedo and Demiurge. At the same time he received a request from the protagonist to launch a festival in E-Rantel to give the humans much needed morale, which he permitted, but also hoped that the protagonist would enjoy the festivities given the last few events. Momonga witnessed Renner's plan to not only fake her death but also weakening the Re-Estize Kingdom by luring her would be rescuers to their deaths. When the plan was a success, Momonga welcomed Renner who became an imp using Fallen Seed. Then at the banquet welcoming her induction, when she inquired about his immortality and how he could endure it, he answered that it was his love for Nazarick. For willingness to join Nazarick, Momonga gifted the new imp a second Fallen Seed for future use on Climb.Mass for the Dead Special Event: Golden Dance Festival of the Fallen
Momonga was later approached by Lupusregina and CZ with a proposal for an offshoot of the Idol Plan called the Bard Plan. The intent was to develop homegrown bards for the Sorcerer Kingdom to spread the reputation of their nation. After some consideration and positive support from Demiurge and Albedo, Momonga agreed to permit the plan. When Demiurge suggested that the protagonist be brought in on the plan, he rejected the request as the homunculus was already busy with managing E-Rantel. Instead he brought Narberal to assist the maids on the plan and had Pandora's Actor supply the musical instruments for their band.
Later when the group decided to create a rock band, Momonga was baffled by their selection. However after learning about the anti-establishment themes and how rock could be used to create a image that the Sorcerer Kingdom allowed critics, he realized it could be weaponized to lower the guards of foreign agents. He then approved the plan, or as everyone assumed to his his ulterior intent, as he wanted it to succeed. Momonga saw the final results of the Bard Plan with experimental creation of Βγδth and their finale live show with LittleMasStar. After the show, Momonga move forward to begin planning to implement it in E-Rantel, by first introducing the rock instruments into Arwintar as per the suggestion of Lupusregina.Mass for the Dead Special Event: Rock the Pleiades
In a meeting with Albedo and Demiurge, he became aware that there was some hype in Casino Resort Nazarick, due to the exhibition of the Momonga Hanger made by Albedo. After being informed of the new changes by Demiurge at the casino, Momonga went to investigate the facility while invisible and had Shalltear ask question for him so as not to disturb the staff and general maids visiting the area. His presence was nearly given up by Lupusregina, who then was recruited by Momonga to collect information from the maids on how to improve the gaming area.
When the information was brought to Albedo and Demiurge on that some of the general maids were just stockpiling complementary chips and not actively playing at the tables, he approved Albedo's idea to host a event there to liven things up. For incentive, Momonga helped to create some limit-time items some which were handwritten signatures of his. On the day of the "Rare Item Acquisition Day", Momonga permitted the maids free time for three whole days so as they could participate in the casino event as an experiment. Momonga then observed the casino experiment from afar. After its relative success of seeing two maid competing and stoking excitement in the casino, Momonga directed Albedo and Demiurge to start working with the protagonist to see if such a plan could be implemented in E-Rantel.Mass for the Dead Special Event: Casino Resort 2nd Bet
In the time of the two newly turned imp newcomers, Climb and Renner, induction to Nazarick, Momonga gifted Climb a new suit of armor as a "mark of welcome". In actuality the armor was a collar with enchants to ensure Climb could be controlled should he go against Nazarick. Renner having been placed in charge of Nazarick's claimed island, reported through Albedo that the fog surrounding the island actually revealed that it was part of an archipelago situated on the coast of an unknown continent. Not only that Renner's lizardmen investigation teams discovered that the islands were infested with Chaos Beasts. Momonga and his aids were interested to know where the monsters originated and managed to locate where the source through a map of the Chaos Beasts dispersal numbers.
It was believed that the monsters were actively hunting intelligent beings in the are present. Momonga decided that it was best for the Sorcerer Kingdom to reach out to these possible people. And although the islands existed outside of Nazarick and should be under the purview of Demiurge who is in charge of external investigation, Albedo argued that the investigation was still technically an internal matter as the [Gate] connected the islands was under her control and through her subordinate Renner. Momonga approved of Albedo's initiative to volunteer herself for the mission and her willingness to maintain her relationship with Renner as a superior. He ruled in the Overseer Guardian's favor and allowed Narberal to assist her in the follow-up investigation of the islands.
For the mission, Momonga witnessed Albedo and Narberal equip themselves in new ninja-theme swimsuits though after they left he had regrets for not saying anything as he was worried their choice of attire would come back an haunt him. When they returned, Momonga learned from them that there were no intelligent beings on any of the islands, and that the Chaos Beasts had merely targeted the local wildlife and remained at the Crack that spawned them. In addition he learned that Albedo managed to fool Climb who was on the mission of why he and Renner faced some hostility from the NPCs of Nazarick, by fabricating a lie that the Sorcerer Kingdom had negative experience with outsiders, which in turn alleviated his wariness towards them and replaced it with sympathy. 
After Demiurge left to make arrangements to quarantine the island with the Crack, things got out of hand when Albedo tried to seduce him to "help" explain her ninja-swimsuit. Predicting she was going on her sex-crazed rampages, Momonga called the Eight-Edge Assassins to protect him and restrain the Overseer Guardian.Mass for the Dead Special Event: Islands of the Unknown and Chaos
Momonga would receive a call from Soi in E-Rantel about an illegal gambling den in the Re-Estize Kingdom. In which the boss of the den was using the protagonist's achievements for their own purposes. However the detail that caught him were descriptions of items that sounded like slot machines, causing him to suspect there might be influences of a player. Given that Nazarick was in the process of implementing a casino strategy plan, Momonga viewed the illegal gambling den as a competitor that needed to be dealt with. 
He received a visit from Demiurge and the undead informed the demon of the den. By coincidence the Floor Guardian was just about to deliver information on the establishment, causing the demon to misconceive the idea Momonga was all-knowing. Through Demiurge suggestions, Momonga had Soi take point on the investigation, and had Shizuni and Ku escort her. The Overlord was kept in the loop of the status of the investigation by Soi as Shizuni and Ku infiltrated the place as bodyguards. The investigation concluded with the capture of the boss of the den, being Succulent and his imprisonment in the Frozen Prison. Momonga was given credit for his thoughtfulness of conveying orders to Soi to maintain due diligence that allowed Nazarick such boons. The image was very positive Momonga had little incentive to dissuade them. As for the slot machines, Momonga hoped more light could be shed on them after Demiurge finished his studies.Mass for the Dead Special Event: Harvest Moon Survey
Momonga would receive some information from the protagonist about the possibility of using "hot spring therapy" to improve the physical and mental health of the humans in E-Rantel, by taking inspiration from the stories of bathhouses in the Dwarf Kingdom from Tsuibayaya. Momonga discussed this with Albedo and Demiurge who agreed that they knew little about dwarven bathing habits and that the idea warranted investigation. After Momonga diverted Yuri and Entoma to interview Zenberu who was more familiar with dwarven culture, he then authorized a expedition for the protagonist to lead to do a survey of the bathhouses. 
For the mission, Soi volunteered to join, while Sebas and Lupusregina were included to act as escorts to watch the protagonist or any signs of trouble from Enhela. While the mission was to see if the dwarven bathhouses had any unique health properties that Nazarick could benefit from, Momonga had an order to Sebas to get the protagonist to relax as he noticed the homunculus was overworking himself.
Later after some days, Momonga received a [Message] from Sebas reporting some unfortunate news. Said news was that the Frost Dragon ruling Feo Berkana had destroyed the famed bathhouse of the city, leaving the dwarves in dismay. With Momonga's permission, Sebas proposed to renovate the bathhouse for the dwarves, arguing that leaving them like this would decrease their productivity and be damaging for the Sorcerer Kingdom. In addition Momonga believed it was a good opportunity to showcase some of the bathing theme inventions and open a new market for his nation.
The renovations at Momonga's suggestion incorporate designs from Spa Resort Nazarick, which were well received by the dwarves. The expedition returned to Nazarick to report their success, bringing gifts from the Dwarf Kingdom from not just the dwarves but the Frost Dragon. The gifts from the dwarves were expected but the ones from the dragon were perplexing to Momonga as it was more like a tribute. However he did not press the issue of how his subordinates made the dragon pay tribute as he was satisfied in the goodwill they did for the dwarves.Mass for the Dead Special Event: Thermae Dwarf 
Momonga and his aides received a request from the lizardmen via Renner, on what they would like to receive as a reward. It pertained to two items, one being an ice room and also a statue of Momonga. The first request was approved by Momonga, though the idea of having another statue of himself, especially one being used to idolized him was out of the question. He managed to deny the request on the ground of not willing to dilute Demiurge's masterpiece with a replica.
Though after he informed Cocytus of the plan to allow the creation of an ice room on the island claimed by Nazarick, the Floor Guardian and Renner brought before him a proposal to add an ice statue of him inside the ice room. By listing the benefits of idol worship and inserting his image into the lizardmen's belief's system, before the Floor Guardians, who were receptive to the idea, Momonga had no choice but to approve of the plan to keep up his image of a knowledgeable king. Before he approved of it, he made it clear that the lizardmen had to accept the feature to the ice room which led to Renner leading a delegation to the lizardmen in the Wetlands to inform them of the ice statue.
After Renner returned from her foraging mission in the Azerlisia Mountains and installed the ice room and statue on the island, Momonga received her first hand report. Upon its completion he called it a success, leading to a Christmas feast on the 6th Floor. Before leading on with a toast for the holiday event, Momonga approached Slimeko at the party to give his regards to the protagonist and even bring some souvenirs for his servant.mass for the Dead Special Event: An Ice Room Is Built and a Holy Night Is Celebrated
At the arrival of New Year's Eve, the whole of Nazarick celebrated the holiday in advance to strengthen Shiro in order to fight his evil counterpart. Momonga escorted Shiro during all the activities to acquire the Seven Lucky God Key Items. Since all seven items needed to appear in order for the White Mochi King to appear, Nazarick had time to prepare. During that time Shiro researched all New Year's activities in Ashurbanipal, before finally coming with the idea to celebrate the "first sunrise." Though such an activity would require Shiro to actually go out of Nazarick to the Azerlisia Mountains. Momonga wanting to see the outside of Nazarick, volunteered to accompany.
The idea was resisted by his subordinates, but after giving an explanation that this tour outside Nazarick was a "New Year's visit" and a way to inspect his realm, they relented, when Albedo decided to tag along. For the mood of the event, Momonga along with Lupusregina dressed in Shinto priest/priestess outfits. With his escorts, Momonga visited the Tob Forests, Great Lake, and Feo Jera. While some of the denizens were fearful of his appearance and sudden visit, the undead won them over using "New Year gifts" prepared by Pandora' Actor. On the final leg of the journey which was Feo Berkana, where Momonga met the Frost Dragon and presented a Sapphire Slime as a gift, he unknowingly intimidated the dragon who though the undead came to kill it. In order to prevent that, the dragon offered its treasure in return and submitted in giving the group a ride to the summit of the mountains. Thanks to the mountain, the dragon and Momonga bringing an eggplant on the trip, it completed the hatsuyume set that was supposed to grant good luck.
Upon the return to Nazarick, Momonga witnessed Shiro acquire the last key item and lead them to the Bishamonten Shrine to fight the White Mochi King. After his defeat, Momonga led everyone to a banquet held in the Canteen. Momonga later send a New Year's card to the protagonist sending his best wishes for the spring and have a meeting with his loyal Floor Guardians and listen how they talk about using the experience from the event to further study the Sea of Possibilities through Shiro. Although he was disappointed in the group were reading too much into his actions, as he just merely wanted to have fun with Shiro, he was warmed that the Floor Guardians used Shiro's relationship with Momonga as a example that the protagonist though hailing from the same alternative realm was just as loyal.Mass for the Dead Special Event: Azerlisia's First Sunrise
A report came that New Six Arms was contracted by Emperor Jircniv to steal an item called the Blood Oath from the Anti-Imperial Faction. Since Lupusregina and CZ were volunteered by Zero, success of the mission was paramount. Momonga ordered Yuri to begin training the two Pleiades in etiquette as well as permitting Renner to provide assistance due to her background in noble circles. 
After they were deemed ready and having succeeded in the retrieval of the Blood Oath, with the names contained being copied for Demiurge to study, the possibilities of etiquette training was realized to further infiltrating higher social circles of human society. Because of that it was eventually planned new courses of training would be given to the rest of the denizens of Nazarick, though a fight nearly broke out between Albedo and Shalltear over who got to be Momonga's potential dance partner for the etiquette training. However Aura defused the fight stating Lupusregina should be the most qualified person as she had prior training.Mass for the Dead Special Event: A Young Lady Casting a Shadow of Ambition 
Shortly after receiving news from the protagonist stationed in E-Rantel, concerning a send-off party for the volunteers in the rescue mission to the "other side" of the Crack, Momonga held a meeting with his loyal Floor Guardians on how to proceed. As the nations of the Quadripartite Alliance would send its representatives at this gathering, it would make sense to have the Sorcerer Kingdom send a representative. Initially Albedo would have gone to the send-off party, but Demiurge made a suggestion that their nation should not conform to the expectations of the other nations, by sending their Prime Minister. 
To avoid making the ceremony at the event to formal, more likeable delegates were needed. Hence Aura and Mare were given the task by Momonga to be goodwill ambassadors for the Sorcerer Kingdom. His decision was accepted by Demiurge and Albedo, with a hint of sly expectation that escaped Momonga. Later new information was passed from E-Rantel, that the mysterious Antilene Heran Fouche from the Theocracy would also be attending. Given the oddity of a half-elf held a high post in the Theocracy, Albedo and Demiurge assumed that Momonga anticipated this due to his selection of Aura and Mare, as a tactic to gather intel on the girl. Of course that was not the case, as Momonga simply selected the dark elves since he wanted them to have fun.
Still the opportunity to gather intel on Antilene was too good not to pass up. Besides having Aura and Mare befriend the half-elf, Shalltear was ordered to reunite with the girl under her adventurer identity, Shall. For extra security in case of any plot of the Theocracy, Momonga assigned Sebas Tian and Narberal to go undercover in E-Rantel. Momonga though was questioned by Sebas on the operation as it seemed a bit too fastidious to try and gather some information on an unknown, suggesting the plan could risk their own agents in being in danger. Their earned a fierce rebuke from Demiurge who was the overseer of the plan to investigate Antilene. The butler and demon's bickering gave Momonga a brief memory of his old friends Ulbert and Touch Me, though in the end he ruled in favor of Demiurge to produce results for the plan.
At the end of the operation, very little information was gleamed from Antilene, save that she was regarded as a treasure to the higher-ups of her nation and lived a sheltered life. While the plan to befriend Antilene went off shiningly, Sebas accused Demiurge of putting the safety of the agents at risk when he incited a trio of humans to attack the undercover Floor Guardians, without any prior notification. Whilst their argument, it reminded Momonga of better days in his guild, causing him to laugh at the sight. In a good mood, Momonga decided to host a celebration of their success.Mass for the Dead Special Event: Achievements for Tomorrow, Variations of the Past 
After the protagonist returned from the "other side" with the Four Kingdoms Rescue Team, Momonga alerted the adventurer that Enhela may have made his move, reporting that several cities in the Re-Estize Kingdom and Baharuth Empire were engulfed in miasma.Mass for the Dead Chapter 17: Eve of the Storm
Although the information on the chaos in the other nations happened within a few hours, Momonga interpreted the events to be a coordinated attack. The miasma had spread within a single night from the situated Cracks and infecting many people in the inhabited cities, turning them into feral creatures. Nazarick was only able to learn of what was happening thanks to the Shadow Demons stationed in various locations. But it was theorized by Momonga that everything was the work of Enhela. 
His main attention was E-Rantel, which sad to say was among the cities in turmoil. Despite the many resources pumped into the city, Momonga had to admit that E-Rantel could not be separated from disaster as it appeared to be synonymous with it. In regards on what to do in the current crisis, while on a [Message] call with the protagonist, the homunculus wanted to save E-Rantel and be a hero. 
And while many of the Floor Guardians believed that cutting their losses would be smart, Momonga agreed with the protagonist as saving E-Rantel was the best choice in a worst situation. Since they had no inkling of the intentions of their opponent for causing this strife, Momonga deemed that they would use their operation to save E-Rantel and collect as much information as possible. As even the most minuscule could be of use to protect Nazarick.
Since the Sorcerer Kingdom possessed a possible cure to decontaminate the afflicted, there was argument that the cure could be a double-edge sword as, while it freed those under the influence of miasma corruption, few humans could gain racial enhancements as displayed by Gazef Stronoff. In the end Momonga decided that it was a risk that he could accept as strengthening humanity could make them more useful pawns.
Momonga was monitoring the negotiation between the protagonist and Enhela, who attempted to appeal to the adventurer to come and join him and his creator in their great work to evolve and save humanity. The information being relayed through summons, cause Momonga to become more disturbed by what he learned, from Enhela abilities which could easily surpass a Floor Guardian level NPC like Sebas Tian, to the world-breaking abilities like "Hacking" and "Divine Right" to the identity of Enhela's patron deity, the Devourer of the Nine Worlds.
When the protagonist rejected the priest's offer a second time, Enhela enacted his next gambit. A voice reverberated through Nazraick and was heard by all within the dungeon. Momonga sensing danger ordered all the NPCs in Nazarick to evacuate and relocate to the Central Mausoleum. After regrouping with those that escape, Momonga found that Enhela was brought the field agents there as well. It was then Enhela revealed that the spilling of miasma from every Crack in the New World was indeed his work, as part of an elaborate plan to flush out the location of the protagonist's base. Not only that Enhela revealed that using "hacking" he had usurped control over Nazarick. 
Upon hearing this many NPCs so desired to kill the human usurper, and Momonga had to command them to restrain themselves as he knew Enhela was not a foe they could take lightly. If they wished to see Nazarick unharmed and to avoid further conflict, Enhela demanded that the protagonist join him and release his full might as a creation of their god. After Enhela teleported to the Throne Room to wait for their response, Momonga declared to the assembled group that they would no accept the terms. Instead he believed that there was still hope to retake Nazarick, by launching a raid to oust Enhela out and began making plans to reconquer the dungeon.Mass for the Dead Chapter 18: Salvation of Mankind
Momonga would lead a raid into the dungeon. Five team would take five different routes into Nazarick to reconquer it. Due to the NPCs regarding his safety of the utmost importance, his team was composed of the dark elf twins and Albedo. Normally Momonga would have objected to such bias, he permitted it due to the uncertain situation. Aware that the protagonist was still a target, he assigned him to Shalltear's team, guarded by Solution and Pandora's Actor.
Under his leadership, the Overlord led his team in a recreated Takemikazuchi Shrine against a replica White Mochi King. After defeating it, they emerged on the 10th Floor, the first team to do so, followed by Shalltear's team. They were greeted by Enhela who welcomed them to talk. While many of the NPCs wanted to attack him, Momonga ordered to stay their hand so he could gain some information on the priest's intentions. Though before the priest could have his say, Momonga gave a run down of what he, and his Floor Guardians', believed to be the main motivation for Enhela's actions. He deduced that the priest took Nazarick to use as a bargaining chip to force the protagonist to comply and accept his lineage as a creation of the Sea of Possibilities.
But it also pointed out that Enhela did so to divided Nazarick's forces as he was wary of a united front. This led Momonga to believe that Enhela's Divine Right which was granted by the Devourer of the Nine Worlds, was not as powerful as the originator. As proof, Momonga had noticed that for all Enhela's power he could not reign in or control the 8th Floor Hierarchy. Additionally he suspected that the priest was acting independently and not under the orders of the World Enemy, as victory would have already been lost, which led to Momonga to conclude that the entity was not in the New World currently and perhaps devouring another world elsewhere. Momonga even had a broad understanding of Enhela's limits to controlling Nazarick as he could not overly alter the dungeon without the prevention of the Ariadne System. 
His grasp of the situation impressed his opponent, even though Momonga kept it to himself that he parroted most of what Albedo and the other said about this matter over Enhela's grasp over Nazarick. When talks turned over to Enhela trying to convince him to join him as a brother, he was rejected. This led to a breakdown of talks and fighting to ensue. Momonga ordered Solution to stay out of the fight so she could protect the homunculus and Slimeko. Despite the combined powers of himself and the NPCs and summons from two raid teams, they were all defeated and left helpless as the priest approached the protagonist.
Momonga and the others witnessed Enhela kill Solution and he captured the protagonist and then prepared to kill the protagonist to have him awaken his Divine Right power. But before the blow was struck, Slimeko, having been given a secret directive by Momonga, used her ability to exchange her life for the protagonist, sacrificing herself. The selfless act put the protagonist on the edge and caused him to awaken his power, but remained loyal to Momonga and Nazarick.
By then the other three teams arrived to reinforce Momonga and the others. Together they fought Enhela, finally managing to slay the priest and end his hold over Nazarick. In the aftermath of the battle, Momonga revived Solution, though was unable to do the same for Slimeko, as she was a summon, and existence that could not be brought back to life. Momonga mourned slime who he came to like, but now with Slimeko was gone, her role as Surako needed to be filled to avoid suspicion from the public in E-Rantel. Hence he had Doppel-Slimeko take her role. 
A month later Momonga held a meeting over the threat of the Devourer of the Nine Worlds. Though Momonga knew of the World Enemy, from his time in YGGDRASIL, its current abilities and appearance, was totally different from what he knew. To learn more about this danger, he authorized Albedo's team to research the Devourer of the Nine Worlds.Mass for the Dead Chapter 19: The Battle to Conquer Nazarick
Momonga would receive a communique from Lupusregina, reporting that while out on patrol in the Azerlisia Mountains from the Tob Forest, Aura and Mare encountered Antilene and another woman named Rei. Later on as the Floor Guardians interacted with the women from the Theocracy, earning their trust, Aura reported to Momonga on their status. Momonga inquired about Rei, as the woman while not on the level of Antilene as a warrior was described as a powerful magic caster by the standards of the New World. He pondered if Rei was a Theocracy dignitary or someone that the half-elf was close to.
Aura informed Momonga that she invited the pair to join on a hunt of the Ice Chaos Beasts, which the Overlord found acceptable as it would give them some comprehension on their capabilities. When he heard that the women from the Theocracy lack equipment for the cold, Momonga thought of allowing them to borrow equipment from the Sorcerer Kingdom. 
Normally he had no objection on lending equipment, but given that the other party were members of the Theocracy, Momonga was worried that they would obtain information from the items. The solution would be to give them equipment that was less powerful, but Momonga wanted to gain some information, and believed that such a risk would be worth it. So he told Aura that he would arrange for Pandora's Actor to send some equipment for the cold via skeletons. 
Another aspect he asked for Aura to keep an eye on was what kind of training Rei was aiming for while fighting the Chaos Beasts, discretely if possible. And so when the dark elves and Lupusregina returned to Nazarick, Momonga heard that they were able to defeat the Ice Chaos Beasts without much issue. From their report he learned that the Theocracy agents did not bring any winter equipment due to it being part of their spiritual training. And while it was not much, Momonga believed that the Sorcerer Kingdom at least now knew about Antilene and her friend. 
Embarrassing to say, Momonga found himself a target of adoration for his role "discovering" a new trait of the Ice Chas Beasts where the quantity and quality of contaminated soil affects the strength of the cold air emitted by them. Demiurge attributed this discovery to Momonga's, even though the undead had no idea what. However the undead was glad that the information could be used to strength his kingdom. Though out of consideration to the Sorcerer Kingdom's allies, the mountain dwarves he ordered Demiurge to pass the information to them. 
On Momonga's thoughts on the Theocracy, if there are other powerful people in that country besides Antielen, there was a possibility that the puppetization plan will be distorted in the future. Momonga understood too well that he always kept a certain distance from the Theocracy, but in order to prepare for such a situation, he may need to find some reason to investigate the situation inside. And that even though Enhela had been destroyed, he could not let his guard on the Theocracy. Even if another enemy like Enhela does not emerge from the Devourer, it would not be strange if a threat other than a player was lurking about. So Momonga vowed that even if he were to encounter such a being again, he must protect Nazarick and the NPCs at all costs.Mass for the Dead Special Event: Valkyrie Oblige 
== Trivia ==
* According to Maruyama, only in the Web Novel, Ainz’s academic background extended to high school and university rather than just elementary level.Syosetsu Blog: December 26th 2012
* In the Web Novel story, Ainz was thought to be one of the Thirteen Heroes.
* Momonga renamed himself as Ainz Ooal Gown so that guild members or players may know of the guilds existence.
* Nigun of the Sunlight Scripture assumed Ainz's true identity to be one of the Evil Deities.
* Under his adventurer persona as Momon, he holds the moniker 'Dark Hero' that refers to his black plate armor and heroic combat prowess. Evileye speculated that Momon is a God-kin, beings with the blood of Players in their veins, due to his display of power that surpasses humans.
* The Slane Theocracy's cardinals have almost mistaken him for one of the Six Great Gods, Surshana known as the God of Death, but quickly dismissed that idea.
* Both the villagers of Carne Village and the lizardman tribes of the Great Lake have built their own respective statue of Ainz Ooal Gown as a sign of loyalty to him.
* Due to Ainz's illusion spell, the Swords of Darkness believed that judging from his facial appearance which is black hair and eyes visually, they see people like him are commonplace in the South.
* Ainz was ranked dead last/the lowest on Maruyama's Governing Ranking, adding that his abilities would be mediocre if not for him being like a god to the New World's relatively weak inhabitants.Overlord Volume 12 Author Thoughts
*The name Momonga in Japanese is translated as "flying squirrel" and was chosen due to Momonga's poor taste in names.Overlord: The Undead Oh! Chapter 65 
*The first raid boss Momonga fought was a Dragon Boss that he fought togther with Touch Me.Overlord: The Undead Oh! Chapter 74 
== Quotes ==
* (To the Staff of Ainz Ooal Gown): "Should we get going, symbol of our guild? No, that’s not it. let us go, symbol of our guild."
* (To Demiurge): "As long as we do not know anything about the beings which live in this world, I can only say that your idea is foolish. For all we know, we might be miniscule weaklings in this world. However, conquering this world might be quite interesting."
* (To the Knights): "You dare to chase little girls, but don’t have the courage to stand against enemies?" 
* (To the Knights):"Do not cause any trouble here. If you choose to not listen to my advice, next time you and your country will burn together." 
* (To Albedo about Humans): "Well, upon meeting the humans here, I could only muster enough empathy to treat them as insects, but after conversing with them, I’m starting to see them as small animals."
* (To Nigun): "The deal that I mentioned before is that I hope that you would quietly surrender your lives, this way you can be spared from physical pain. Otherwise, if you resist, which would be very stupid of you would have to pay the cost of dying in despair and misery."
* (To his Guild Members): "My friends, what do you think about me hogging this glorious name? Will you be happy? Or displeased? Tell me if you have any feedback, tell me this name isn’t mine alone. I will change back and use Momonga without hesitation."
* (To Albedo about Shalltear): "I am the one known as the Guildmaster of Ainz Ooal Gown. When engaging in PvP, the actual chance of victory is high, invincible against even those with flawless builds. How can I lose to the type of person who solely relies on their attribute? Furthermore, the most important fact is the strong bond I have with Peroroncino. Know that this battle was over even before it had begun Shalltear."
* (To the Unknown Enemies) “I will definitely make you deeply regret your own foolishness. Do not think you can get away so easily when you anger us, Ainz Ooal Gown.”
* (To Himself): "I am Ainz Ooal Gown. With that name at stake, there can be no defeat."
* (To Himself): "Hooh...Ainz-sama's plan, huh. I see. A special plan concocted by someone with the same name as me. Making the Baharuth Empire ally with and struggle against Nazarick was part of that plan too, huh...I have no idea what that's all about. If only I could ask this Ainz fellow about it!"
* (To Shalltear): "Realize now, Shalltear. You face Ainz Ooal Gown, with the combined might of all Forty-One Supreme Beings from the beginning, you had no chance of victory."
* (To Himself): "Repaying good with good and evil with evil. This is the norm of the world."
* (To Gustav about Neia): "I gave her those orders because I felt she could carry them out. However, interfering in the matter by weight of your position as a superior is comparable to slighting my judgment. That displeases me to an extent."
* (To Neia): "Umu...Neia Baraja. Don't make me repeat myself so many times. Failure is the mother of success. The consequences of not relying on me and instead thinking for yourself, even if they should end up being failure, should not be feared, but embraced. This is because they are the failures necessary for success."
* (To a foreign citizen formerly captured by Bafolks): "Originally, the weak like yourselves should have been defended by the Holy Kingdom, those who should have been strong...I really do pity you. If you were under my protection -- under the protection of my country, the Sorcerer Kingdom, something like this could not possibly happen. That is because I would have used all my strength to protect the people and strike down the Bafolk."
* (To Himself in front of the foreign citizen): "Even I would be oppressed if I were weak. Therefore one cannot forget to seek strength. I need to engrave into my heart the fact that beings of comparable power to myself most definitely do exist."
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