Edo Singularity

The Edo Singularity is a singularity manifested upon the blankened Earth during the Human Order Revision Incident. Located in 17th century Japan, it is created and maintained by Beast III/L for the purpose of accelerating her growth process. Similar to the Subcategory Singularities encountered during the Remnant Order, it is a unique singularity designated as a Humanity Destruction Zone. It is visited by Chaldea Security Organization in the undertaking of the Grand Order to restore Earth and the Human Order.
The events of Chaldea's visit to this Singularity are covered in an event of Cosmos of the Lostbelt; . It is designated as "Lostbelt No. 4 Prelude", preceding the events of the Indian Lostbelt.
==Setting==
As a result of what happened to the gods in the Indian Lostbelt, the normally suppressed presence of Mara inside Kama became stronger, and she began to turn into a Beast thanks to Beast III/R's defeat. In order to avoid the Counter Force from detecting the presence of a Beast, Mara sought a place to hide while her transformation completes. 
She eventually found the Ooku in Edo Castle upon sensing the dying regrets of Lady Kasuga to want to continue nurturing the Tokugawa. however sensed the incoming threat, and ordered Matsudaira Nobutsuna to protect the Tokugawa. Understanding the Ooku would be the epicenter of this threat, they ensured Kasuga's soul would be protected once the threat occurred. 
Establishing a personal chamber inside the Ooku, Mara invited inside to indulge in her flesh daily until he forgets about everything else. Afterwards, she obtained his soul and then followed his karmic threads to nearly everyone inside the Ooku to take their souls as well. Following that, she took all the souls from the rest of Edo Castle and from the surrounding area. She then used Kasuga's karmic bonds to the Tokugawa to steal the souls of the Tokugawa Shoguns in the past and future to serve as the anchors of the Ooku. 
Afterwards, she used her karmic bonds with Ritsuka to reach into Chaldea and tried to bring them to the Ooku, but Sion Eltnam Sokaris protected them. So she brainwashed Goredolf Musik into disabling Chaldea's protection and rayshift himself to the Singularity. From there, she used his connections to reverse summon nearly everyone in Chaldea into the Ooku. Once they rayshifted to the Ooku, Mara froze them while their spiritron avatars were still being established. The exception was Parvati, who resisted, and granted her own Spirit Origin to Kasuga's lost soul to keep her in the world.
Using the souls of everyone from Edo Castle and Chaldea, Mara reconstructed the Ooku into a labyrinth that is six floors deep, with the souls of the shogun serving as its lynchpins. Each floor of her Ooku was designed to be impossible for any human to pass unless they break one of the each floor represents. However doing so activates a curse that turns them into a Tokugawa because the Ooku is a place for the shogun to indulge in pleasure, so conceptually, any human who indulges in its pleasures is the shogun. Before the arrival of Chaldea, Goredolf became the first victim of the curse. Mara also connected the Ooku to herself, and since her existence is conceptually linked to the universe, it is both a recreation of the universe and her body.
Tenkai transformed Nobutsuna's organs into containing the same energy as Kama's Ooku to counteract her, and Nobutsuna scattered them throughout the Ooku. He also placed a spell on Nobutsuna with the concept of "one whose actions oppose the Tokugawa" to eventually act in conjunction in the cards to counteract Mara's false Tokugawa authority. At some point afterwards, Nobutsuna joined Mara under the pretense of being a traitor to the Tokugawa, so his body can be filled with Anti-Tokugawa properties for his and Tenkai's plan to protect the Tokugawa.
==History==
===Prologue===
In Ritsuka’s room, they and Mash discuss how Sion Eltnam Sokaris and Captain are working to modify the Shadow Border so they can reach the Atlantic Lostbelt, though they need a part only found in the Indian Lostbelt. Mash doesn’t know what if that part is unique to that Lostbelt or what, only that at this point Sion and Captain are making the Border ready for said part. Sion thought preparations would be done after they returned from the Chinese Lostbelt, but that didn’t go as planned. Captain said it should be done soon though.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Prologue
Mash realizes she hasn’t seen anyone today, not even Fou when the alarm suddenly sounds off. Sion warns Novum Chaldea is under attack and orders Ritsuka and Mash to the command room.
At the command room, Mash confirms Sion’s fears that there is no one left in Chaldea. Sion explains to Ritsuka and Mash she immediately cut off their cause-and-effect interference to protect them the moment she noticed the control room staff, along with Leonardo da Vinci and Sherlock Holmes, were gone. She is ashamed she could only protect Ritsuka, Mash, and herself in time, especially since she had already cut herself off from human history. Save for the three of them, everyone in Chaldea is gone. There are also no summonable Servants despite the Spirit Origin Graph still functioning.
Sion deduces everyone was forcibly rayshifted using her Coffin as a catalyst. Such a feat might be possible with CHALDEAS, but reverse-summoning should be impossible with Novum Chaldea’s systems. lack any way to support reverse-summoning. Sion has a couple of admittedly absurd theories on how it could work, though, given the circumstances.
She suspects the culprit is unrelated to the Crypters since they have no reason to leave the Lostbelts. She also still has a faint connection to Captain, but the fact he’s yet to take action indicates to her he trapped along with everyone else.
Mash fears the non-mages among the staff disappeared upon arrival, unable to withstand the rayshift. Sion doubts that is the case, however, as everyone was rayshifted to a space beyond standard history. She theorizes the enemy’s goal was capture as they froze everyone while they were still in spiritron form to eliminate any resistance.
She reveals their destination is a Singularity, but it’s trying to interfere with Proper Human History akin to a Lostbelt. It might be a hybrid, similar to the Shinjuku and Shimosa Subcategory Singularities. Sion therefore dubs it a Humanity Destruction Zone.
The coordinates are Edo period Japan. But Sion warns Ritsuka and Mash she cannot let both of them go since needs someone to observe and confirm Ritsuka’s existence. Mash realizes she’ll need to stay when Sion says she needs someone who can do the work of three. She is still concerned about leaving Ritsuka by themselves, however.
Kiara Sessyoin then enters the room, being the only Servant to have avoided capture, and decides to go with Ritsuka, who doesn’t remember her. Sion is shocked to see her, but she can tell she is one of Ritsuka’s Servants from the magical energy flow. This is happily within her calculations, though, because if she couldn’t see Kiara since she is of the extra class Alter Ego, then the enemy must have overlooked her as well. Kiara admits she differs from the other Extra Servants thanks to her Inde…something Skill.
Sion then discovers the signal of the last Servant to be reverse summoned, having resisted and escaped after the rayshift was complete. She orders Ritsuka to find the Servant and reestablish their contract. Ritsuka and Kiara rayshift to the Singularity.
They arrive at , which was the closest location to the signal, but it is eerily quiet. They find who they assume to be Parvati wearing a pink kimono, but she asserts she is the overseer of Edo Castle’s —Lady Kasuga. Her attitude becomes more friendly though once Parvati herself reveals Ritsuka is an acquittance of hers.
She explains Parvati rescued her when she was about to die from illness, believing the gods want her to use the goddess’ body and powers to resolve the incident occurring at the castle, ignoring Parvati’s insistence otherwise. As for the incident she speaks of, she reveals everyone disappeared from the castle and the Ooku itself has been turned into a deep labyrinth.
=== Tokugawa's Invitation ===
Kiara is pleased to meet Parvati, though Parvati senses something in the former she’ll have to deal with quickly and decisively if the situation calls for it. She thinks it should be fine, though, as she senses Kiara has a “dam” within her and suspects that is why in the Singularity. Kiara supposes only a goddess could sense her connection to the Singularity, albeit vaguely. But while something about Kiara nags her, Parvati knows there are more pressing matters, namely what she is sensing from the Ooku, something only she can deal with.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Act 1: Tokugawa's Invitation
Asked for more testimony by Sion, Parvati confesses she came across Kasuga’s soul while being drawn to Edo and saved her on a whim. She had realized sharing her Spirit Origin was the only to save Kasuga. But thanks to that, her own definition became less clear, which she thinks is why she could escape the enemy’s forced summoning. Both Sion and Ritsuka agree what happened with Chaldea and Edo Castle is definitely connected.
But while discussing everyone where could be, the heroes are suddenly contacted by Goredolf Musik wearing a golden kimono. However, he has no sense of his original identity and introduces himself as the shogun, Tokugawa Goredolf. He invites the heroes into the Ooku before ending contact.
Sion surmises the enemy brainwashed Goredolf into using his security clearance to disable all the command room’s protections. After which, he was the first one to be rayshifted and from there the enemy used his connections to reverse summon everyone in Chaldea. Such a feat would require more magical energy than a Holy Grail can provide. But considering Goredolf appears to be in the Ooku, the Chaldeans figure everyone else must be there as well, so they have to go in.
Kasuga confesses the current shogun, Tokugawa Iemitsu, has also disappeared, having not said so before since if word got out it would be an unprecedented crisis for the shogunate and, by extension, Japan. She believes he is in the Ooku like everyone else and requests the heroes’ help in rescuing him. Parvati agrees, saying Kasuga’s knowledge will prove valuable.
The heroes enter the Ooku through the entrance reserved solely for the shogun, but it's nigh unrecognizable to Kasuga. There are other entrances, but it seems only this one leads to the new labyrinthine Ooku. Sion surmises the Ooku has been spatially reconstructed. Kasuga also finds the Indian decorum strange.
She then takes notice of the multi-armed female automatons, whom she assumes are attendants, guarding the door that actually leads into the Ooku. Mash feels the automatons are vaguely Indian, much like the corridor. Kasuga orders the attendants to step aside lest she strike them down. But seeing she forgot her naginata, she leaves it to Parvati.
The heroes destroy the automatons, but both Kiara and Parvati noticed the latter never attacked. Nevertheless, the heroes proceed into the labyrinth.
=== The Audience ===
====Part One====
Upon entering, the door locks behind the heroes. Kasuga corrects Kiara’s misconceptions that the Ooku is nothing than a place to indulge in carnal pleasures. The real Ooku is complex, clean, spacious, and pleasant, and it is reserved for the shogun’s wife and concubines to produce an heir to the Tokugawa. But hearing Parvati had the same misconception as Kiara, Kasuga decides to lecture everyone about the Ooku.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Act 2: The Audience
Before she can, though, Matsudaira Nobutsuna confronts the heroes. Given her different appearance, Nobutsuna doesn’t recognize Kasuga until she calls him by his childhood name, Choushirou, and scolds him for forgetting the woman who raised him. She also notices he seems younger than she remembers, which Nobutsuna says is thanks to his new lord.
Kasuga demands to know who his new lord is. Nobutsuna reveals Iemitsu isn’t dead, but he is no longer here either, thus he now serves the new Ooku’s lord. His new lord is not Goredolf, however. He then calls for attendants, forcing the heroes to fight.
After the battle, the heroes notice Nobutsuna is gone. Mash hopes to get some information out of him next time they see him since given he now serves the one behind the incident, he might know where Goredolf and the others are.
====Part Two====
A flashback shows Goredolf was no longer brainwashed when he first arrived in the Ooku. While trying to find a way out, he came across some attendants. They proved hostile, so he destroyed them all, surprised by how easy it was for him. He continued to destroy them as more came.
====Part Three ====
Returning to the present, the heroes just finished destroying more attendants. Kiara and Parvati both agree the attendants’ only threat is their numbers, seeing how they weak are. Kiara requests not to destroy any more attendants than necessary, which everyone agrees to. Internally, she suspects the attendants were made weak on purpose as part of an insidious trap, one she cannot let Ritsuka fall into.
Elsewhere, while speaking to him, Nobutsuna’s new lord reveals she designed the Ooku so the only way to proceed through it is by behaving in a certain way. She is disappointed, though the heroes aren’t enjoying themselves as much as they’re supposed, for which blames Parvati.
But changing topics, she asks Nobutsuna how things are coming with the one she left in his care. Nobutsuna admits there hasn’t been much progress. His new lord encourages him to keep at it until he is satisfied, but she also thinks it’ll be faster for him to give up and turn them into a pillar already. Nobutsuna would like to keep at it for a while longer, however.
His new lord then decides she will go out and greet the heroes herself.
Meanwhile, following another battle, Parvati gathers the attendants’ remains and prays over them. She knows her actions might be perceived as naivete and weakness by the enemy, but she cannot ignore her innate kindness. It is not something her other selves, Kali and Durga, would ever do. But she reminds the others she is currently manifesting via the innate goodness in the girl serving as her vessel. That goddess also repels any disposition unable to acclimate to it, so right now Parvati is nothing but herself. Yet despite her disposition making her unsuitable for battle, she feels there is a significant reason she was called upon instead of Kali or Durga.
====Part Four====
Entering a spacious room, the heroes are welcomed by a young girl. She and Parvati seem to know one another, with the former hating the latter. Ritsuka notices both of them have the same vessel. The girl explains Parvati possessed the vessel’s good side while she possessed her dark side.
Parvati reveals the girl is Kama, the Indian god of love. Kama blames Parvati for what her husband did to her. Parvati demands why Kama is in the Ooku and her relation to it. Kama initially dismisses Parvati’s question until she sees the latter is sharing her body with Kasuga. She reveals she created the new Ooku using a special ingredient.
She asks the heroes if they felt pleasure from clearing the 1st floor. Kiara answers she did not. After a brief pause, Kama reveals the attendants were made incredibly weak to make the heroes ignore the “do not kill” precept. She was certain they would enjoy it, but they didn’t, much to her disappointment.
But Kama asks Kiara who she is, knowing about her other than she isn’t on her “guest list”. Kiara claims she is just an ordinary Servant. Kama dislikes Kiara is here, but accepts it all the same.
Ritsuka demands to know where everyone is, to which Kama states she determines whether those she has captured live or die. She says they may be freed if the heroes reach the Ooku’s lowest floor. She then sics a large female ghost on the heroes and escapes to await them at the labyrinth’s bottom.
After the ghost is destroyed, Kiara finds a pillbox with the Tokugawa emblem that Sion assumes to be the ghost’s catalyst. Ritsuka is enveloped in a light from the pillbox and hears the voices of an , his critics, and a sweet voiced woman who supports him. They were the only one heard it though, nor was it logged.
Kasuga notices the name engraved onto the pillbox, but she doesn’t recognize it. Mash explains Tsunayoshi is the fifth Tokugawa shogun, which confuses Kasuga since the era is the third generation of the Tokugawa. Sion explains Tsunayoshi is Iemitsu’s fourth son, delighting Kasuga to know the Tokugawa will continue into the future.
Sion notices something spiritual contained within the pillbox and packaged it in such a way to limit its attributes. If installed into Ritsuka’s Mystic Code, it may help with their expedition of the Ooku. Ritsuka agrees, seeing it to everyone’s benefit. After they install it with Sion’s instructions, Ritsuka and the others continue their expedition.
===The Truth of Materials===
====Part One====
While continuing to explore the labyrinth, Parvati notices and picks up a Hanafuda card. Sion reveals it is actually part of the Ooku and asks the heroes to find more for further analysis.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Interlude: The Truth of Materials
====Part Two====
Later, the heroes destroy another destroy ghost, and the light from its pillbox envelopes Ritsuka. They hear a sweet voiced woman comforting who was upset at others for calling him a figurehead because he’s a child.
Kiara notices the name , the seventh Tokugawa shogun, engraved on the pillbox. Kasuga is pleased to hear Iemitsu has a great grandson and asks about his reign. Mash doesn’t have the heart to tell her Ietsugu became shogun when he was still a small child, only to die a few years later. But Sion convinces Kasuga to drop her inquiry by making her realize knowledge of the future could disrupt everything that’s meant to happen, surprising Kiara by how insight the latter is. Ritsuka installs the pillbox like they did the previous one.
====Part Three====
Meanwhile, Nobutsuna tries once again to convince Yagyu Munenori to join him and Kama. But Munenori still refuses, questioning how one of Iemitsu’s most trusted advisors could so easily abandon the shogunate. Nobutsuna thinks it’s natural for him to join Kama since she already toppled the shogunate and it’s hopeless for them to defeat a god.>
But he still respects Munenori, which is why he wants to convince him to join Kama’s side. It is only by his request and Kama’s good graces, Munenori still remains himself. Kama, if wanted to, could’ve brainwashed him into an attendant like she done with a number of Servants. But Nobutsuna would prefer he join of his own volition. Munenori, however, adamantly refuses to serve the enemies of the Tokugawa.
An attendant suddenly reports to Nobutsuna “guests” have invaded the floor and requests further instructions. Nobutsuna kills her for daring to speak to him without bowing her head, calling it deserved. He doesn’t expect manners from puppets, though, which is why he only wants to keep those with manners by his side. But his patience has its limits, so he hopes Munenori chooses wisely before he becomes part of the Ooku himself.
The heroes enter the room; Ritsuka notices Munenori being absorbed into the pillar behind Nobutsuna. Kasuga questions how a man of Munenori’s skill could become trapped. Munenori doesn’t recognize her, so Kasuga briefly explains her situation.
Sion confirms Munenori is undoubtedly the one from Chaldea, but simultaneously he is giving off the same readings as the Ooku. It is the same for everyone from Chaldea and in Edo Castle, revealing everyone’s lifeforce was used as materials to build the new Ooku. Thus everyone was abducted not after the new Ooku was built but to build it in the first place.
Nobutsuna reveals not everyone abducted was used as construction material. Kama is keeping some souls that lack physical form on the bottom floor. Kiara and Sion, therefore, conclude they need there in order to rescue everyone. But Munenori needs to be rescued first, which Sion says is possible as he’s yet to become part of the Ooku. She cannot promise anything, but she thinks there is a good chance if she can analyze him.
Nobutsuna calls on a giant female ghost. Sion tells Parvati to make contact with Munenori to get her more precise data on how to remove him safely from the pillar. Kiara, meanwhile, fights the ghost by herself.
As the battle continues, Sion’s analysis concludes they need something with the same affinity as the Ooku to free Munenori. Parvati then notices the card she picked up is heating up. Sion realizes it has the same affinity as the Ooku, so it can be used to free Munenori.
After Munenori is freed, the ghost tries to attack Parvati. Munenori steps in front of her and, as his sword is still spiritually locked, he catches the ghost’s naginata with his bare hands. Kiara uses this chance to destroy the ghost. Nobutsuna retreats, claiming to know nothing of Kama’s plans
Mash concludes the Ooku is a Singularity which, if ignored, could lead to the collapse of humanity. That was Goetia’s goal with his Seven Singularities, but it’s unknown if that is Kama’s goal or just a side effect of her true goal.
After Mash confirms there are no abnormalities with his Spirit Origin, Munenori agrees with Kasuga they need to rescue Iemitsu as soon as possible. He tells Ritsuka he cannot abandon his former lord and is pleased to hear they want Iemitsu along with everyone else.
From another pillbox, Ritsuka hears the voices of a frustrated at his critics and the multiple crises occurring under his rule, and a sweet voiced woman who supports him.
Sion sees the name on the pillbox is , the thirteenth Tokugawa shogun. Ritsuka installs it into their Mystic Code like they did with the previous ones. Munenori is perplexed, so Mash explains the situation to him before the heroes move on to the next floor.
===Path of Insincerity===
====Part One====
Earlier, while still himself, Goredolf continued to explore the labyrinth, now bored with killing attendants. He soon encountered more attendants, but these were non-hostile and offered to help him relax because they thought he was the shogun. He presumed they were confusing him with someone else, but nonetheless took them up on their offer.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Act 3: Path of Insincerity
====Part Two====
Returning to the present, Nobutsuna informs Kama of Munenori’s rescue. He is expecting punishment for his failure, but Kama tells him failure is only inevitable for humans. She hates all humans, but she still loves them, for she is the god of love.
Continuing to explore the labyrinth, Kasuga is surprised Ritsuka knows Lady Chacha and Oda Nobunaga. Munenori is perplexed she didn’t seem surprised to learn he was a Heroic Spirit and that it was RItsuka’s mission to save the world. Kasuga admits she was surprised, but she has no trouble believing someone like Munenori could undertake such a quest.
A group of attendants then approach the heroes, thinking Ritsuka is the shogun. Sion assumes the attendants on the current floor had their moods changed and suggests going with the attendants’ assumption to avoid a fight. Ritsuka declares they are the shogun, but the attendants attack when Kasuga takes offense to Ritsuka’s blatant lie.
After destroying the attendants, the heroes continue their expedition, only to find themselves getting repeatedly lost. Mash tries her best to help guide them.
====Part Three====
Unfortunately, Mash’s mapping is unable to help them find their way. They decide to rest in a room they found while Sion tries to analyze the map data.
But looking at the map data herself, Kiara theorizes they are more likely to get more lost on this floor the more they follow their desire to move forward. She therefore believes the only way forward is to “lie”, by which she means choosing the path that seems incorrect. The others appreciate Kiara’s help, but Ritsuka feels they shouldn’t depend too much on her if it can be helped.
====Part Four====
Following Kiara’s advice, the heroes eventually reach the end of the floor, where they encounter Kama again. She is disappointed they took the “honest” route, pointing out they could’ve gotten here faster if they had the attendants do their jobs. But she doesn’t actually care either way since she will still hate them regardless.
Parvati asks Kama if she turned everyone from Edo Castle and Chaldea into building materials for the Ooku to get revenge on her. Kama laughs at her for thinking that. Parvati admits it was a preposterous question to ask, but she needed to ask. Now she understands she is here to stop whatever Kama is planning.
Ritsuka asks Kama why she abducted everyone. Kama feels there is no need since they’ll figure it out, eventually. She is also just lazy, which is why she isn’t going to try to stop them; their paths only just happened to cross. But she needs the heroes to be welcomed at these major junction points and sics a giant ghost on them.
Kama is already gone by the time the heroes destroy the ghost. Ritsuka picks up another pillbox, but the voice is too short to remember.
Sion doubts whatever Ritsuka is hearing are auditory hallucinations, but she and Mash aren’t detecting whatever it is. She wonders if they’re picking up on tiny oscillations or formless remnants that only last for a split second. Whatever it is, she wants Ritsuka to tell her immediately when it happens again so she can make sure it isn’t anything dangerous.
Kiara sees the name on the pillbox is , the fourth Tokugawa shogun. Kasuga is pleased Ietsuna will succeed his father without issue. He was in the castle with his father when this whole incident happened. Kasuga sees it as her duty as a loyal retainer of the Tokugawa to rescue Ietsuna as well, wondering the pillbox has a connection to him. Sion has been wondering the same thing, but her examination of the pillboxes has yet to verify anything.
Mash reveals communications get more disrupted the deeper the heroes delve into the labyrinth. Verifying Ritsuka’s existence is the priority, though, so communications may be lost at times. But Mash vows to do everything she can to keep that from happening.
Kiara thinks to herself how the Ooku is following a particular pattern, but she decides to keep to herself until she is certain. She also feels there is another more complicated side to Kama. If that is the case, she is in the situation she expected it was. The Ooku is the opposite of what she would have created, but it is indeed a paradise.
=== Remedy for Intoxication ===
====Part One====
Earlier, Goredolf, now wearing the golden kimono he does in the present, was served food and drink by Scheherazade and Mata Hari.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Act 4: Remedy for Intoxication, Part One
====Part Two====
In the present, the heroes come to a hallway reeking of alcohol. Scheherezade and Mata Hari approach them, offering food and drink. Munenori and Sion realize Kama brainwashed them. Kiara confesses she attempted to use her Thesis of the Still Heart Codecast to counteract the brainwashing, yet it had no effect.
Scheherazade and Mata Hari turn hostile when the heroes refuse their services. Munenori eventually knocks out Mata Hari with the back of his word, while Kiara renders Scheherazade unconscious with a spell. Before the communications die, Mash explains that Scheherazade and Mata Hari’s condition is similar to what happened to Munenori before. Parvati thus uses a hanafuda card to undo Kama’s brainwashing.
Neither Scheherazade nor Mata Hari have any memory of their time under Kama’s control, so Ritsuka fills them in, per Munenori’s suggestion. After being told, the women remember everything and join the heroes to rescue everyone.
====Part Three====
Later, Scheherazade finds it strange Ritsuka is becoming intoxicated from the alcohol fumes alone. Munenori demands Kiara come clean because earlier, she demonstrated she knows more about the Ooku than the rest of them. He believes she can explain the change in Ritsuka’s condition.
Kiara confesses she has noticed a pattern. The 1st floor was to abstain from killing; 2nd floor was to abstain from lying; the 3rd and current floor is to abstain from drinking. Each floor’s theme is based on the Five Precepts of Buddhism and it is only by breaking them could the heroes proceed through the Ooku. It is therefore plausible Ritsuka’s condition is the result of not abiding, so they might need to get drunk to counteract it.
Mata Hari considers that too dangerous though as it means going along with Kama’s plan, especially when her goal is still unknown. Parvati wonders if there is another way for them to proceed without playing into Kama’s hands. Mata Hari realizes she can use her Noble Phantasm to give Ritsuka a simulation of being drunk and uses on them with their approval. It seems to prove successful in exploiting the loophole in the floor’s rule.
====Part Extra====
Continuing their expedition, the heroes try following the path with the least alcoholic fumes, but they hit a dead-end. Kasuga suggests they track back and follow the paths reeking of alcohol.
====Giant Wandering Maidservant, and a Trifling Illusion (A)====
Along the way, they destroy another ghost and obtain the pillbox of , the second Tokugawa shogun.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Giant Wandering Maidservant, and a Trifling Illusion (A)
====Part Four====
The heroes eventually reach the end of the floor. Nobutsuna appears to see if they’re following the laws of the Ooku, but like he suspected, Scheherazade and Mata Hari are no longer attendants and Ritsuka’s intoxication is fake. He remains silent in the face of Kiara’s suspicions he only came to check if they’re breaking each floor’s precept.
Munenori tells Nobutsuna they’ve already determined the Ooku has a connection with the Five Precepts. Thus, he will only ask him once if he is certain he doesn’t know Kama’s true objective. Nobutsuna refuses to say, believing the heroes can figure it out.
He summons two ghosts to enforce the floor’s mandate of intoxication. But first he warns the heroes none can defy Kama. Her Ooku was made impossible to progress unless they succumb to depravity, and she wants them to delve deeper. Nobutsuna then retreats, leaving the ghosts to attack.<
After the ghosts are destroyed, Ritsuka picks up the pillbox they dropped with the name , the eighth Tokugawa shogun, engraved on it. Mata Hari deactivates her Noble Phantasm. Kiara believes they are two more floors each representing the remaining precepts if her theory is correct. She advises caution from here on out.
=== Key to Steal ===
====Part One====
Earlier on the next floor, Goredolf had succumbed further into the Ooku’s pleasures, but he was annoyed by all the locked doors. He quickly learned each attendant on the floor held a key to said doors when one of them dropped theirs, so he started stealing the keys. At that point, he completely succumbed to the Ooku’s pleasures and believed he was the shogun.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Act 5: Key to Steal
====Part Two====
In the present, the heroes obtain a key from the attendants they just defeated. Ritsuka finds it strange that the floor has so many locked doors. The heroes quickly come to another locked door when Munenori notices two attendants preoccupied with something in the room next to them. There also appears to be a key left unattended.
Mata Hari suggests using her Espionage Skill to sneak past the attendants and steal the key. Kiara deduces the precept represented on the floor is to abstain from stealing. Mata Hari sees no other choice but to break the precepts like Kama expects if that is the only way to progress.
Scheherezade, however, suggests finding another loophole like on the previous floor. She believes it is a question of who steals the keys and breaks the precept, with Ritsuka being the most dangerous option followed by their Servants doing so in their stead. But she wonders if it would go against Kama’s expectations if a Servant had something to steal the keys. She then tells the story of Alibaba, summoning the forty thieves to steal the key.
Passing into the next room, Kasuga notices the next door doesn’t have a key but a pedestal with a hollow nearby. Munenori notices numerous attendants in the nearby, along with an ornament that seems would be a perfect for the hollow. Scheherazade tells another story to steal it.
====Part Extra====
The heroes hit a dead-end in the next room. They recall earlier seeing several objects that were missing pieces of themselves, such as a handless table clock. Kiara surmises Kama designed this floor easier to navigate the more one steals. Scheherazade then tells more stories to find those missing pieces so they can progress.
====Giant Wandering Maidservant, and a Trifling Illusion (B)====
Along the way, they defeat another ghost and obtain the pillbox of , the twelfth Tokugawa shogun.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Giant Wandering Maidservant, and a Trifling Illusion (B)
====???====
The heroes hit another dead-end. However, the wall is completely blank, unlike the rest of the labyrinth, nor does it have any keyholes. Munenori thinks to himself how odd it is the wall reminds him of a man who failed to attain serenity. The heroes move on, but Kiara thinks to herself there is a way past the wall and commits it to memory.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - ???
====Part Four====
Reaching the floor’s end, the heroes encounter Kama once again. Kiara deduces Kama wants them to progress through the Ooku while breaking the Five Precepts, but she doesn’t understand her end goal in that. Kama claims she wants them to give in to depravity, designing her Ooku so they’d feel pleasure from breaking the Five Precepts.
Then, becoming a young woman, she tries to tempt Ritsuka into breaking the precept of not stealing, but the others defend them. But Kama tells them they have no other choice, for she has the key to the next floor. She summons a ghost to make things more interesting.
Kiara calls the matter by which Kama has done things pathetic. Normally Kama wouldn’t let what others say bother her, but for some reason, Kiara infuriates her. She asks who she is since her invitation was only meant for Ritsuka. She also knows she reverse-summoned every Chaldean Servant and converted them into construction materials and her anti-Counter Force defenses are airtight. There shouldn’t have been anyone left, so Kama questions what sort of Servant Kiara is. The heroes fight Kama and the ghost.
Kama and the ghost are defeated and disappear, surprising Parvati that they had beaten the former. Ritsuka picks up the pillbox the ghost dropped, hearing a sweat-voiced woman supporting a shogun who prefers his games over politics.
Afterwards, it is revealed the heroes actually killed a clone of Kama. She congratulates them on taking the key from her and returns to the deepest part of the labyrinth. Despite their concerns about Kama cloning herself, the heroes continue on to the final floor. Kiara is certain everyone knows what the final precept is at this point.
=== Myriad of Women ===
====Part One====
Earlier on the next floor, Goredolf was occupied by Kama clones, who encouraged him to go deeper in.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Act 6: Myriad of Women
====Part Two====
The heroes quickly realize the floor represents the precept to abstain from adultery from all the attendants trying to tempt them. They’re also approached by several Kama clones who intend to seduce them into breaking the fifth precept. They break through the clones, even knowing Kama wants them to fight her since pain and pleasure are, in essence, the same.
====Part Extra====
They eventually hit a dead end, so they decide to follow the paths where there are more Kama clones.
====Part Three====
Reaching the floor’s end, the heroes encounter Nobutsuna, surrounded by Kama clones. He sends the clones and a ghost to attack them.
After the battle is won, Ritsuka picks up the pillbox the ghost dropped and hears the voices of and a sweet-voiced woman who supports him.
Nobutsuna tries to warn the heroes what will happen if they go any further. But he is interrupted by his chronic cough and runs off into the Ooku's innermost chamber without finishing his warning. The heroes follow after him.
===God of Love===
Upon arriving in the labyrinth’s innermost chamber, the heroes are welcomed by Gordolf, who still believes he is a Tokugawa. Kasuga demands to know where Iemitsu is. In response, Kama removes a pillbox from her chest and reveals each pillbox is a shogun's soul, serving as anchors for the Ooku. The one she has is Iemitsu's soul.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Act 7: God of Love
She explains when she first came to the Ooku, she created a personal space--a part of her, in a way--in an empty space inside the real Ooku. She then invited Iemitsu inside when he visited the Ooku and entertained him until he was satisfied and forgot everything else. After obtaining his soul, she followed Iemitsu's connections to gather materials, following them to everyone in the Ooku, Edo Castle, and the surrounding area.
But even with all those souls, she still needed more materials to create her Ooku, so she followed Iemitsu's connection into his past and future. From there, she seized the souls of Tokugawa shoguns from the past and the future and converted them into materials--the pillboxes. They were significant, so she made them into anchors for her Ooku, using them as guidelines when making the other floors. Once she was done, she no longer needed them besides Iemitsu's, so she repurposed them as a power source for the attendants.
Parvati surmises Chaldea was Kama's next target after her Ooku was built. But while she understands how Kama's Ooku was built, she doesn't understand its purpose, suspecting it isn't just for pleasure. Furthermore, she wants to know why Kama targeted Chaldea, wondering if she considers them a threat and if she seeks to destroy humanity.
Kama mocks Parvati for getting it wrong and confesses she didn't have to use the Tokugawas and the Ooku for her plans. It just happened to be the perfect place to fulfill her true goal of drowning Ritsuka in her love. In fact, she was only able to reach into Novum Chaldea because they are connected by fate. But Sion protected them against her, so she had Ritsuka go through her Ooku of their own volition. None of their loopholes worked like they thought for they still accepted her love and made their way to her.
Ritsuka suddenly begins to believe they are a Tokugawa. Nobutsuna reveals Kama's Ooku is a curse designed to turn any who reach the innermost chamber by breaking the Five Precepts into a Tokugawa. Kama adds if the Ooku is defined as a place devoted to the shogun's pleasure, then conceptually anyone who experiences those pleasures is the shogun. Kiara realizes Kama intended to corrupt Ritsuka into a Tokugawa. Kama reveals Goredolf was the first one she invited to her Ooku, calling him the perfect subject for her first Tokugawafication experiment.
Scheherazade considers it impossible for even a Divine Spirit like Kama to create such a massive specialized spell. Kama counters she can, thanks to the power of her love, and all she has to do is prove it. When she does, it strengthens the concept behind her Ooku, which is why she chose a labyrinth design and the Five Precepts.
She tells Ritsuka that no matter how they sin, she will love them unconditionally. Parvati doesn't consider that love but depravity. Nobutsuna says it doesn't matter how it's defined because once someone becomes a Tokugawa, they can never escape Kama's Ooku.
Mata Hari and Kasuga implore Ritsuka to resist while Munenori and Scheherazade fight Kama.
Unfortunately, Munenori finds himself unable to swing his sword like he wants to. The thrill of the battle causes Kama, against her will, to change into an adult woman with burning arms and legs. She tells a confused Parvati that her husband did this to her. She then reveals the innermost chamber is her and changes it into a scenery of the universe.
Parvati realizes what Kama is now. Kama confirms she is indeed Ananga, the formless one, now. Shiva had disintegrated her with his third eye when she shot him with one of her arrows of love to get him out of his deep meditation per the gods' commands. But not only was her body disintegrated, her very existence became vague and hazy.
However, since Shiva is meant to incinerate the universe, and he incinerate Kama, she and the universe became conceptually linked. Kama admits it doesn't make sense, and normally, no one could handle such a thing. But she isn't an ordinary god of love; she is a demon king.
Parvati realizes Kama is now her alternate self, the Demon King Mara. Mara reveals her Ooku's innermost chamber is now her own self-contained universe, meaning everyone is inside her and thus cannot move as they please. She, therefore, tells them to surrender and deprave themselves in her love.
Kiara finds it impossible for Mara to wield the power of the universe like she is, sensing there is more to it. Mara reveals she is an Evil of Humanity, having awoken to the position because the "Right" side was defeated, causing the "scales" to tip to the Left. She has also realized by now Kiara is a fragment of the Right vessel. Kiara confirms she was and asks Mara why she is after Ritsuka.
Mara confesses she sought Ritsuka because they stopped Kiara from maturing when she was still the immature R. By surpassing them, she believes she, the opposite of Kiara, will fully mature. She then changes her form again, her flames now red and now possessing horns, and proclaims she is Beast III, the Beast of Pleasure, the one who will cause all humans to Lapse into depravity--Beast III/L.
She recounts R called herself the embodiment of self-love and tried to gather all the world's love into herself. But R grew too large, leading to her defeat by Servants, and ended up crumbling under her own dead weight. Mara calls herself the polar opposite, wanting to fill all of humanity--the universe--with her love.
Kiara realizes that would end love altogether because when living things are granted infinite love, they are complete and no longer need anything from anyone else, meaning there will not be any love left for new lives. Mara counters that the recipients of her infinite love will enjoy themselves forever. She can satisfy all of humanity's desires, which to her is the same as saving them.
She then implores Ritsuka to give into her love. Mata Hari tries to get them to resist while the others fight Mara.
The heroes are overwhelmed. Kiara thinks she might be able to defeat Mara if she breaks her vow to exist only as a Servant of Chaldea. She doubts, however, that defeating Mara once will end her plans if her suspicion about Beast III/L's nature is true.
Ritsuka continues to resist their Tokugawafication, so Mara has Nobutsuna bring Goredolf over. At Nobutsuna's behest, Goredolf shares a drink with Ritsuka.
Munenori notices his sword feels heavy every time Goredolf talks. Nobutsuna reveals a Tokugawa's authority is strengthened in the Ooku's innermost chamber, and those who know that authority cannot help but obey their words. Mara adds the effect is unconscious and reveals she has the same property as well. It works on an instinctual level for retainers like Munenori, which is why he can barely swing his sword.
But when all seems lost, Kasuga suddenly slaps Goredolf and scolds him. Mara is shocked that Goredolf's Tokugawa authority has no effect on her when it should affect her more since she is just a soul. Kasuga's stern scolding reawakens Goredolf's past trauma with Toole, breaking his mental conditioning.
Mara and Scheherazade question how Kasuga can raise a hand against the shogun when doing so is punishable by death. Kasuga understands that, but she will raise her hand against the shogun if it's absolutely necessary to ensure he is raised properly. If the shogun understands his mistake and her actions are still deemed punishable by death, then she will die proud. She would die happy if her death meant the shogun learns right from wrong.
Kasuga's words enrage Mara, declaring her love is the only love humans need. Goredolf suddenly attacks her, which she easily dodges. He then returns to being a Tokugawa since his reversion to his old self was only temporary.
Kiara decides to hold Mara back while the others escape. She tells them to gather the hanafuda cards to counteract Mara, then expels them from the chamber. Afterward, she fights Mara using her power as a Beast fragment.
Mara seemingly destroys her and waits for Ritsuka to return as they have no other choice but to.
===Tokugawa's End===
The heroes are back outside. Ritsuka's Tokugawafication seems to have stopped. Mash and Sion also re-establish contact.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Act 8: Tokugawa's End
After the current situation is explained to her and Mash, Sion deduces the Counter Force never sent a Grand Servant after Mara because it didn't recognize her as a Beast since she is still immature and hiding in the Ooku. But she recognizes it is far too reckless for them to fight a Beast head-on, so she suggests finding a weakness linked to Mara's other properties.
Munenori recalls Mara had said she was both Tokugawa and the Ooku. But most importantly, she holds a pillbox containing Iemitsu's soul in her body. When he tried to attack her, his sword felt heavy as when Goredolf spoke. Scheherazade adds Mara is linked to Ooku since its inner sanctum is the universe and she is linked to that.
At Sion's request, the heroes tell her and Mash everything that happened after they lost their connection. Sion deduces from all this information that the heroes are still missing a pillbox; that of , the fifteenth and final Tokugawa shogun.
Kasugua is shocked to hear the Tokugawa shogunate will end 200 years from now, but she accepts all great civilizations must come to an end eventually. She asks then what happens to Japan after the Tokugawa are gone, wondering if it returns to when it was in constant conflict. She is relieved to hear from Ritsuka that Japan eventually becomes peaceful after some turbulence. But Munenori surprises her when he informs her the shogunate system is abolished, and the right to rule is returned to the emperor, with governing conducted by representatives chosen by the citizens.
Sion states Yoshinobu abolished the shogunate of his own accord. The act of ending the Tokugawa had set him apart from other shogun, which is probably why the heroes never found his pillbox. Sion analyzed the pillboxes and found they possess properties indicative of that shogun's reign. Thus, Yoshinobu's should have the power to end the Tokugawa and could be used against Mara since she is both the Ooku and Tokugawa.
Munenori recalls the blank wall they found, suspecting there is something hidden behind it. Sion finds it likely whatever Mara is hiding has an adverse effect. She also reassures thanks to the inner Ooku data stuck to Ritsuka's Mystic Code, she was able to modify communications so they can remain in contact even at the very bottom of the Ooku.
Kasuga thinks to herself how in the back of the mind she always knew the Tokugawa's reign would one day end. It is unfortunate, but that is how the world works. Still Kasuga wonders why, for some reason, she feels relief now.
===The Final Tokugawa===
Returning to the blank wall, Munenori is hesitant to cut it down since the Ooku is made out of people from Edo Castle and Chaldea. But Sion assures him he will not kill anyone because they were atomized before being used as construction material and aren't physically bonded. With that reassurance, Munenori slashes the wall without hesitation.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Act 9: The Final Tokugawa
His slash has no effect, however, since the wall has a special seal. Sion senses there is a hidden keyhole, a conceptual/magecraft hole, designed to accommodate a long, thin catalyst like a card. She deduces that the hanafuda cards have the energy to break the seal if all the cards the heroes collected along the way are interested. It is almost as though they exist solely to counteract the Ooku. The heroes then use the cards to break the seal and enter the room beyond.
They find a pillar with a ghost partially fused to it. They destroy the ghost and acquire Yoshinobu's pillbox, yet Ritsuka hears no voices.
Sion scans the pillbox and confirms there are no signs of Mental Pollution or spiritual traps. She worries, however, that since Tokugawafication is a completely new concept, there is no accurate way to measure it. There is also the possibility the pillboxes may induce unforeseen side effects. Progressing through the Ooku may not be the only way to Tokugawafy someone as well.
Per Sion's instructions, Ritsuka adds Yoshinobu's pillbox to their Mystic Code, giving it Anti-Tokugawa properties and granting it an Anti-Tokugawa defensive spell. It cannot, unfortunately, be used to cleanse Ritsuka of their existing Tokugawafication. The best it can do is act as a barrier to keep Mara from exerting her influence any further. It may also be turned into a projectile, like Gandr.
The heroes head back to Mara's chamber, knowing their chances of victory are extremely low.
===Ooku===
====Part One====
Upon returning to Mara’s chamber, Ritsuka activates their Mystic Code to create a barrier that negates Tokugawafication and diminishes the constraints on Munenori. Mara cryptically laughs at the fact the heroes found and are using Yoshinobu’s pillbox before fighting them.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Act 10: Ooku
The heroes appear to have the advantage over Mara since her horns are starting to crack. But Mara mocks them and reveals she planned from the beginning for them to find Yoshinbou’s pillbox. If it was an actual threat to her, she would’ve hidden it better. She wanted them to find it all so they’d despair when they lost with what was meant to be their only hope.
Then, to make it more difficult for Parvati to use her Spirit Origin, she reveals she chose the Ooku to complete her maturation because she sensed the dying Kasuga’s desire to continue loving the Tokugawa. Kasuga is understandably shocked by this revelation. Parvati implores Kasuga to calm down, trying to warn her about what will happen if she, a mere soul, lets the shock get to her.
Mara further reminds Kasuga of the dream she showed her when they first met, a dream where she could raise and coddle every shogun like she did with Iemitsu forever. Sion realizes the voices Ritsuka had been hearing from the pillboxes were residual thoughts left over from Mara’s actions. Mara confirms as much and reveals she reached every shogun via Kasuga’s connections with the Tokugawa.
She further guilts Kasuga into feeling personally responsible for the Tokugawa’s downfall, but she promises to still love her like everyone else. Mash and Mata Hari realize Mara intends to erase all the love people naturally have from existence. It would be a world where the concept of loving one another loses all meaning.
Mara asserts her ability to drive all humans into depravity is already being proven, as Ritsuka’s Tokugawafication is suddenly re-triggered. The Five Precepts were never her true temptations, rather it was the pillboxes. She actually wanted Ritsuka to find and use them all to facilitate their Tokugawafication. Their transformation will soon be complete and when it is, they’ll be what she needs to become a fully mature Beast.
Light suddenly shines from beneath her cracked horns. They shatter, revealing the next stage of her growth, a form she claims proves she has become deeply linked to the space of this chamber. Mash is shocked to read that Mara’s magical energy output has grown even more.
Mara removes the gravity, leaving everyone adrift in space. Scheherazade orders the Djin of the lamp to hold on to Ritsuka. Mara then proves she is the universe by showing every star is her, one for every human, every desire. Humans weren’t designed to survive in outer space, so they cannot hope to defeat a Beast who is the universe. To prove her point, Mara then leaves the heroes floating in the cold darkness of space with the barest minimum of oxygen, all to break Ritsuka’s spirit.
Kasuga remembers she had accepted her incoming demise but at the very last moment she didn’t accept it and wished she could stay and keep loving the Tokugawa. She believes that is why this incident occurred, calling it her punishment for her shamelessness.
Scheherazade unfolds the Magic Carpet for all them to rest on. Sion concludes they need to redefine the chamber to somewhere that isn’t the universe and reinforce that definition for them to stand a chance against Mara. Ritsuka states this place has been the Ooku in their mind.
Kasuga thinks she deserves to die for what she had done and that Parvati should have never saved her. But her final request is to die in the Ooku, which she had dedicated herself to her whole life. She wonders why she isn’t there right now when she remembers what Ritsuka said a moment ago. She realizes her life up to now wasn’t a mistake if an ordinary person like Ritsuka still knows about the Ooku centuries from now. So she needs to take responsibility and fulfill her duties as head of the Ooku. Risen from her despair, she requests Parvati relinquish her.
Meanwhile, Mara tells Nobutsuna she will reward him with lots of extra love for his devotion once she has achieved her goal. But then she notices a light that wasn’t there before. Kasuga proclaims her name will always be spoken alongside the Tokugawa Ooku, so if she is here now, then this place must be the Ooku. A wooden floor suddenly appears.
Earlier, Parvati refused Kasuga’s request because her Spirit Origin is the only thing keeping her in this world. But Kasuga had realized that since Mara used the souls to create her Ooku, then as a soul herself, she should be able to rebuild this place into what the Ooku should be. She only has the feeling she can do it, though, probably because Mara’s formless universe is connected to the Ooku labyrinth, which has form.
Sion understood Kasuga’s logic and believed she could do it, but told her she had nowhere near the power necessary to accomplish it. Kasuga knew that, which is why she requested Scheherazade to tell a story depicting her as the undisputed ruler of the Ooku and Mata Hari to use her Noble Phantasm to make her believe she is like the Kasuga depicted in the story. Sion realized it could work since Kasuga was only a soul now. Scheherazade said she needed time to recite Kasuga’s tale, so Parvati deployed a Bounded Field to slow the flow of time a bit.
After Scheherazade and Mata Hari finished modifying her, Kasuga left Parvati, then she dispersed the darkness and manifested a floor at Sion’s suggestion.
Kasuga remembers the dreams she had on her deathbed. She vows to stop the evil her own weakness created and dreams about raising every shogun properly and steering them away from Mara’s influence. It was only a dream, but it was what she needed to reaffirm who she is. She is synonymous with the Ooku and nothing will ever change that.
Mara is shocked to see there is a floor in her universe. Sion informs Ritsuka she added thrusters to their Mystic Code to keep them upright and a life preservation zone around their head to keep them breathing. The heroes are confident they can fight now they can, are no longer floating, and have a solid foothold. Irritated by their newfound confidence, Mara reminds them of her other selves and the fact Ritsuka’s Tokugawafication is still present.
Nobutsuna suddenly offers the heroes his assistance. Kasuga denounces him as a traitor but Nobutsuna tells her she owes him a favor, revealing it was him and who rescued her soul. Tenkai immediately came to see him the moment he realized Iemitsu was abducted, and the Tokugawa were facing an existential threat. Once they learned the Ooku was the locus of this crisis, they protected Kasuga, the one whom they deemed essential to resolving this crisis. Nobutsuna believes the reason Kasuga can preserve herself in soul form and manipulate soul energy is due to the protection spell Tenkai casted on her when they saved her.
He joined Mara all to protect Tokugawa. But he understood he couldn’t kill her, so he had Tenkai provide him with a less direct form of assistance.
All the sudden he starts coughing up blood. Sion realizes the hanafuda cards were actually made from Nobutsuna’s organs. The cards’ black boxes then all activate at once and are now running a backdoor program that reveals what is already there. Mara is confused by what is happening.
Nobutsuna proclaims himself a traitor to the Tokugawa, his actions thus far proving as much. Sion reveals the cards have inward-facing power as opposed to the outward-facing power of Yoshinobu’s pillbox, meaning they can be used to cleanse RItsuka’s Tokugawafication. Nobutsuna gives his consent to use the cards, willing to give his life for this plan and knowing the heroes have no other choice. The heroes give all the cards to Ritsuka.
====Part Two====
Ritsuka uses the cards to cleanse themselves of their Tokugawafication.
Munenori realizes the butterflies depicted on the cards are from the Matsudaira Clan crest. Nobutsuna reveals that Tenkai engraved his body with a spell at the cost of his own life. He requests Munenori to kill him as he is an enemy of the Tokugawa. Munenori calls him loyal, but Nobutsuna insists he is a traitor, saying he must be for this plan to work. Munenori kills him without hesitation.
Nobutsuna’s soul is released, becoming just like Kasuga, either thanks to Tenkai’s spell or his own sheer willpower. But like Kasuga, he too can now change his shape. Munenori expects said shape will be a blade meant to be the Tokugawa’s mortal enemy.
A katana emerges from Nobutsuna’s body; his soul has become a false Muramasa blade. Munenori takes it to destroy the false Tokugawa. Sion deduces. Nobutsuna had turned his entire body into the ultimate Anti-Tokugawa weapon, honing his blade—himself—this whole time until someone worthy of wielding him could come and end the false Tokugawa.
Mara admits she knew Nobutsuna was betraying, though she was surprised he helped Kasuga escape. She also knew about the truth about the cards. She only kept Nobutsuna around so she could see the look on his face when his plan failed, but he succeeded against her expectations.
Mata Hari tells Mara that Nobutsuna was far more loyal than she could conceive, which is why she failed to see the full scope of his plan. Mara admits she had never expected what Nobutsuna was thinking. It disgusts her he betrayed the Tokugawa in order to fill himself with Anti-Tokugawa properties and chose to be killed to become a Tokugawa-Slayer and help defeat her.
Kasuga understands what Nobutsuna was thinking, though, calling his actions to protect the Tokugawa a pure expression of his love. Mara utterly refuses to accept any love that isn't her own, especially the sort she knows nothing about.
Parvati tells Mara that is why she and humanity will never get along. There are many forms of love, but Mara wants to control all that herself. If she grows to full maturity, it would mean the end of the world, even the universe. Parvati, therefore, proclaims she will stop her here and now, no matter what.
Matar Hari says she wouldn't want love to be monopolized as it was thanks to love she became a Heroic Spirit.
Scheherezade knows (though admittedly she doesn't know how she does) that love is precious, calling it the only thing that makes her forget her fear of death.
Mash admits she only knows about love in theory, but everyone has told her she will know when she feels it and that it's meant to be shared with someone special. She looks forward to that day and knows she will never experience it with Mara's one-sided depravity, calling that desire not love.
The heroes fight Mara after she admits her plan to satisfy all desires will lead to stagnation.
As Munenori kills her other selves at surprising speed, Mara eventually understands he will only kill her if she continues to be Tokugawa and the Ooku. She thus removes said properties from herself, but that allows Kasuga full control of the Ooku and change it into what it's meant to look like.
On Ritsuka's command, Mata Hari, Scheherazade, and Munenori attack Mara.
Kasuga tells Mara there is more to love than indulgence, with tough love being equally as important. She suspects despite calling herself the embodiment of love Mara knows nothing about the kind of love that comes from watching someone grow and improve. She then exerts her authority over the Ooku to expel Mara from it.
Mara is expelled outside and into the air. Parvati tells her it's over, believing love isn't meant to be one-sided. She thinks either love has no clear definition or it's something gods can never truly understand. As the god of love, Kama should have been the closest to figuring it out, instead she was consumed by depravity. Parvati thus declares she will show her what she believes love to be as her final gift to her, the love for her husband, and strike Mara with Trishula Shakti.
In agony, Mara asserts she is always the victim. Whether she is the god or demon king of love, people always blame her for there not being enough love in the world. That is why she tried to give them her infinite love as a form of revenge. She knew a god meant to love others would never be loved herself, so she had to love--dominate--everyone to keep herself from feeling like the victim again. She is destroyed, lamenting she couldn't dominate every human with her love.
Commenting on Mara's final words, Kasuga admits it does feel good to love, especially when the recipients are weak and in need of protection because it makes you feel needed and that you matter. It can be terrifying to end that, but breaking from that obsession to love someone forever is a love that guardians like her must one day be willing to embrace. If you truly love something, you must be willing to let it go.
===Epilogue===
With Mara destroyed, everyone will return to where they belong. Goredolf has also returned to normal.Fate/Grand Order: Cosmos in the Lostbelt - Ooku: Tokugawa's World-Changing Labyrinth - Epilogue
Kasuga gives Ritsuka the Grail she found inside the labyrinth's central support pillar earlier. Ritsuka is sad for Kasuga, but she tells them goodbyes are meant to be said with a smile. She has accepted her death. If it wasn't for the situation and Parvati's aid, she would have gone to the afterlife long ago. All this was a dream she had right before ascending to Nirvana, so it's best that it's over.
Munenori begins to return to Chaldea. Kasuga imagines herself fighting alongside him as another of Ritsuka's Servants. Sion comments that while her Spirit Origin isn't stronger to summon Kasuga normally, there are other ways to help with that nowadays. They may see her again if not in the way they expect. Kasuga decides to hold onto that hope just in case.
Parvati also hopes to see Kasuga again someday too. The two of them were one and the same for a while after all, and at this point, she considers her a dear friend.
Feeling her time is almost up, Kasuga thanks Mata Hari and Scheherezade for their help. She then tells Ritsuka they will become a great person one day so long as they stay on their current path. She thanks everyone and disappears, hoping to one day repay their kindness. Munenori returns to Chaldea immediately afterward.
Parvati starts to disappear as well, having expended all she had to defeat Mara. But she keeps herself materialized to reveal Kama became Beast III because her Mara was stronger. Such a thing should be impossible, as the Hindu gods keep Mara under constant supervision. Parvati, therefore, theorizes something happened to the gods when the Human Order Revision occurred. Mash realizes there may be a connection in the Indian Lostbelt. Parvati apologizes she won’t be able to help in India, but she’ll send someone to help.
After she disappears, Ritsuka, Mata Hari, and Scheherazade return to Chaldea.
Back at Chaldea, everything has returned to normal. A new firewall is set up to ensure another attack like Kama's never occurs again. Da Vinci swears from now on to prepare for any and every possible situation, no matter how outlandish. Holmes is disappointed he missed the chance to personally observe a Beast.
As for Goredolf, Da Vinci is making him run on a high-speed treadmill. He gained considerable weight with all his feasting and got a D- on everything for the emergency physical Da Vinci gave him when they returned. He needs to lose weight, or else it will affect his ability to do his job, so Da Vinci is having him undergo her special Get Fit Quick program.
Meanwhile, in her inner universe, Kama finds herself in the giant hands of Kiara, much to her irritation. Kiara apparently felt pity for her because even in her own mind, she would submit himself to self-incineration for her failure, possessing no love for herself. Kama realizes Kiara can exist in her inner universe because she had incinerated her.
Kiara denies her accusations she wants to absorb to become a fully realized Beast III. The two of them could never merge, for Kama is about giving while Kiara is about taking. They may be both Beasts born of pleasure, but they are completely opposed.
She then grants Kama the ability to be summoned as Ritsuka's Servant, calling it her punishment and a chance to redeem herself and learn about mutual love. Kama accepts it as a chance to learn about the love Kasuga spoke of and to irritate Parvati with her seductions.
Meanwhile, back in her ailing body, Kasuga looks at the moonlit sky, commenting Japan will still know peace even after Tokugawa's reign ends. She doubts Iemitsu would punish her for saying that like her lady-in-waiting fears. She is certain she raised him properly so he'd want what is best for Japan and expects he'd laugh off her remark. But she tells her confused lady-in-waiting what speaks of is a dream centuries from now. She then passes away in her sleep.
==Participants==
Servants
Designation	Identity 	Affiliation
Alter Ego 	Kiara Sessyoin	Ritsuka Fujimaru
Lancer 	 	Ritsuka Fujimaru
Saber 	 	Ritsuka Fujimaru
Assassin 	 	Ritsuka Fujimaru
Caster 	 	Ritsuka Fujimaru
Assassin 	 	N/A
Non-Servants
Designation	Identity 	Affiliation
Human 	 	Tokugawa Shogunate
Human 	Goredolf Musik	Tokugawa Shogunate (false)
Human 	 	Kama (false)
Beast III/L	/ 	N/A
==References==
Category:Locations in Fate/Grand Order‎
Category:Singularity
Category:Human Order Revision
Category:Japan
Category:Castles
Category:Edo
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