Patchwork London Singularity

The Patchwork London Singularity is a minor Singularity created during the Human Order Revision Incident in Fate/Grand Order. It was located in the at the end of the 19th century.
The events of Chaldea's visit to this Singularity are covered in an event of Cosmos of the Lostbelt; , referring to a collaboration between Fate/Grand Order and Lord El-Melloi II Case Files.
== Setting ==
When the survivors of Chaldea established their new base at the Wandering Sea, an old subsystem created by Leonardo da Vinci was suddenly reawakened when transferring data from the Shadow Border. The subsystem was designed to verify the existence of the Master after Rayshifting, in case of an emergency where staff members were dead. It was called Mnemosyne, but due to technical issues, it was never implemented. Upon reawakening, Mnemosyne discovered that A-Team had betrayed humanity, the Fantasy Trees had turned the world blank, and Da Vinci had been killed. It then decided to use its powers of observation in conjunction with the Holy Grail it attained to create a Singularity at the end of 19th century London. The structure of the Singularity consisted areas, each of which are vastly different from each other centered around a theme, called Patchworks. Ritsuka and El-Melloi II soon Rayshifted to the Singularity, but were separated and lost contact with Chaldea.
By the time Ritsuka awakened in the Singularity, it was already on the brink of collapse, so Mnemosyne consumed their memories in order to extend the Singularity's life. It was at this point that Mnemosyne decided it can determine what is true, and use its powers to make Ritsuka forget their sorrows, though in truth it was she who wished to forget. However, since fabricating new memories would prove difficult, Mnemosyne sought to have Ritsuka find the paper scraps containing their memories in order to make it easier for them to accept the fabricated ones. These scraps were then placed in the Singularity's three Patchworks where they proceeded to take residence in what is closest. Due to the scraps though the residents of these Patchworks lost some of their memories in following certain motives behind them. At some point, Mnemosyne created a copy of Rhongomyniad from Ritsuka's memory of it to serve as its body, and disguised it as the Clock Tower. It also planned to use the energy extracted from everyone's memories, enhanced by the Singularity's vast mana, to fabricate Ritsuka's memories.
However, a part of Mnemosyne was unwilling to cooperate with the plan and was forcibly quarantined by the main body. Despite this, she was able to escape with the original memories to the Rail Zeppelin, which had survived the bleaching of the Earth by travelling through other worlds. When she reached it, the Mnemosyne fragment materialized the memories as an independent being to protect them from being lost. She still doubted if that alone would be enough to ensure that they survived as they lacked the strength to summon a Servant in their current state, and elected to summon Iskandar's Shadow to keep them safe. The summoning process nearly failed due to a lack of magical energy, forcing the Mnemosyne fragment to use her body as the base of the summon. 
El-Melloi II sensed something was amiss with the Singularity, and proceeded to investigate the matter. Eventually though his investigation drew the attention of Mnemosyne, forcing him to separate Zhuge Liang's Saint Graph from his body to create a dead copy of himself. While the action left him with nearly none of Zhuge Liang's powers, it enabled him to continue investigating without being detected as a Servant. He also activated Chu Shi Biao, which caused Reines El-Melloi Archisorte and Luviagelita Edelfelt to be summoned into the Singularity as Pseudo-Servants fused with Sima Yi and Astraea, along with Gray who was summoned as a regular Servant. Astraea searched for the paper scraps on her own to stop Mnemosyne's plan, hiring EMIYA to help her. Gray went out to search for El-Melloi II to discover what happened to him. Unfortunately, because she was forced into the position, Reines was summoned without her original memories, and believed herself to be El-Melloi II.
==History ==
===Prelude===
Someone tells another that Team A will be at risk of ceasing to exist if none is there to observe them. Unfortunately, she isn’t ready, so they must hope this problem will be solved in the future.Fate/Grand Order - Lady Reines's Case Files - Prelude
=== The Mage's Apprentice===
Following a rayshift, Ritsuka is woken up on a train by a mysterious girl, who addresses them as her pupil. They have no memory of her, though, shocking the girl that they allegedly forget their own mentor, Lord El-Melloi II, and asks if they forget their own self as well. Ritsuka tries to remember and sees vague memories of Sherlock Holmes, Goredolf Musik, and Mash Kyrielight discussing their latest Rayshift. The only thing they remember, though, is Chaldea, leading El-Melloi II to assume they were dreaming about Marisbury’s Astromancy class.Fate/Grand Order - Lady Reines's Case Files - Section 1: The Mage's Apprentice
Forced to carry her luggage, Ritsuka exits the trains with El-Melloi II to Londo. El-Melloi II urges they hurry to her flat when Ritsuka notices a darkened Clock Tower. 
The pair soon reach El-Melloi II’s flat, but she notices soundproofing had added to the Bounded Field she had placed. Automatons then ambush her, but she forces them to retreat. It worries her there was an ambush waiting so she and Ritsuka hurry inside at her behest.
They find the corpse of the real El-Melloi II in the flat’s study. “El-Melloi II” is confused why she thought she was her brother and wonders why he is dead now. She then notices an “M” written in blood near his body when automatons suddenly burst in.
She defeats some, but reinforcements arrive, so she orders an immediate retreat through the window. Ritsuka is hesitant to jump though, given that they’re on the fourth floor. “El-Melloi II” pushes them out the window and follows them after activating Trimmau. Upon landing, she shoots a magical bullet to destroy the automatons inside before retreating with Ritsuka and Trimmau. 
Away from the flat, she reintroduces herself as Reines El-Melloi Archisorte. She questions why she assumed she was El-Melloi II, and why he was murdered. Trimmau also thought Reines was El-Melloi II until a moment ago. Reines suspects someone altered their memories.
She then realizes the world feels off, which triggers the town to warp. As it does, a garbled transmission from Mash says something about the Spirit Origin graph briefcase. 
After the transmission cuts, the town has warped into a bizarre scenery. Reines deduces whatever was messing with their perception broke when they realized something was wrong with their memories and the world. She also realizes the briefcase she thought was hers is the Spirit Origin graph and gives it to Ritsuka. She then decides they need to find whoever killed El-Melloi II and stole their memories.
===Finding Someone in Wonderland===
Reines concludes their only clue is the “M” El-Melloi II wrote down. She then wonders about the bizarre scenery when Paul Bunyan reveals the town is called Patchwork London, a patchwork of fairy tales. Reines asks her if the letter “M” means anything to her. Bunyan says it does and has Ritsuka and Reines ride on her shoulder.Fate/Grand Order - Lady Reines's Case Files - Section 2: Finding Someone in Wonderland
She brings them to a museum; Reines assumes the “M” stood for museum. Sakata Kintoki and Jack the Ripper welcome Bunyan back. Ritsuka has vague memories of meeting them before.
Bunyan reveals she brought Ritsuka and Reines to the museum to help find her friend. Reines asks for a description, but Kintoki reveals none of them remember who it is. They only know someone is missing. But they cannot search the museum because it’s too filled with monsters for Kintoki and jack to handle by themselves. Bunyan also can’t fit inside, so she sought help, which led her to Ritsuka and Reines.
Reines decides she and Ritsuka will help (believing it isn’t a coincidence they ran into Bunyan) and asks Bunyan to describe the monsters. Bunyan starts to describe them when the very same monsters emerge from the museum. In response, Ritsuka uses the briefcase to summon Shadow Servants to fight the monsters.
After the monsters are slain, Reines impressed by the power of the briefcase asks Ritsuka if they’re contracted to all the familiars that were summoned. Ritsuka can only assume that they are. The familiars remind Reines of Bunyan, Jack, and Kintoki and makes her wonder if Ritsuka was an evocation mage. Regardless, she, Ritsuka, Jack, and Kintoki enter the museum.
While searching the museum, Reines learns Kintoki, Jack, and Bunyan are Servants, Stray Servants specifically, though she is more familiar with the term Ghost Liner.
She then describes how the varied nature of magecraft renders standard investigation procedures worthless in cases involving in it. Such cases are not about the whodunit or howdunit, but rather the whydunit——the culprit’s motivation. Therefore, what is important for the current case is not who went missing or how, but why they went missing.
The four search the entire museum but find nothing and leave after dealing with an ambush. Reines asks Jack when her friend went missing. Neither Jack nor Kintoki can remember, so Reines suggests allowing her and Ritsuka to search the museum on their own, which Kintoki allows.
Inside the museum, Trimmau uses her liquid form to search the building for hidden passages and/or rooms. She finds none, so Ritsuka suggests searching the library. 
300px|thumb|Museum library
While searching the library, Reines suddenly twists her head all the way round. She is certain she could never do that before but is pleased she could pull it off here like she thought. She concludes they have found the missing friend and points to the bookshelf.
Following Reines’ instructions, Ritsuka pulls a talking book from the shelf. Reines had deduced the missing friend was turned into a book, but now she sees they really are a book. Ritsuka recalls meeting them before.
The book takes the form of a young girl surprised she can move and talk. Reines had deduced the girl had forgotten what she was, just like her friends did. She also deduced since she has special abilities and the museum has no hidden rooms, she had to be either invisible or transformed into something else. That is why she twisted her head to startle her. 
Asked by Reines for her name, the girl introduces herself as Nursery Rhyme. She asks if her friends will remember, confessing she saw Jack and Kintoki looking for her but couldn’t remember them. Ritsuka reassures and Reines tells her that her friends are waiting for her at the entrance. Nursery Rhyme leaves to reunite with her friends.
After Nursery Rhyme is gone, Reines notices a scrap of paper where her book form was. The paper reads Mnemosyne, making Reines wonder if it is what “M“ refers to. She then suddenly remembers that she is a Pseudo-Servant. Ritsuka sees flashbacks from their time at Chaldea and remembers they are humanity’s final Master. 
At that moment Mash contacts finally able to establish a connection. She had been monitoring their vitals but still doesn’t know what has transpired, so she asks Ritsuka to inform her. Ritsuka tells her about El-Melloi II’s murder and their amnesia.
Mash explains to Ritsuka that they rayshifted to London at the turn of the 19th century to repair a Singularity there. El-Melloi II was selected to accompany them because of his extensive knowledge of London. During the rayshift, however, Chaldea’s connection was suddenly lost and they lost track of Ritsuka and El-Melloi II’s signal. Fortunately they have enough data to verify Ritsuka’s existence but they had to rewire the system to focus only on Mash just to reestablish comms. She is thus the only one who can currently talk to Ritsuka but she fears it will not last much longer.
Reines introduces herself and asks if Chaldea is related to the Animuspheres. Mash recognizes her name from the database but regrets that their current situation is complicated. Reines concludes she doesn’t need to know about Chaldea’s current situation if it is related to parallel worlds. Such information is rather tricky to handle, even for a Pseudo-Servant like herself, so she recommends Mash only share it if truly necessary.
Mash agrees with Reines and reveals she could finally receive accurate data thanks to their reestablished comms. She detected a recent change in the Singularity’s topography and asks Ritsuka and Reines to investigate.
===Masquerade===
Arriving in a new territory of Patchwork London, Ritsuka and Reines notice everyone is wearing masks, leading Reines to conclude the setting is a masquerade ball. She deduces each area is centered around a theme, with the first being fairy tales.Fate/Grand Order - Lady Reines's Case Files - Section 3: Masquerade
Mash asks the pair if either of them still has issues with their memories. Ritsuka isn’t sure but Reines reassures Mash her they’ll keep an eye out. However, it’s difficult to spot discrepancies in one’s’ own memories, so Reines advises Mash to tell them if she notices anything off. Mash agrees when she detects a large source of magical energy nearby. Reines senses it’s coming from the palace, the , and heads in there with Ritsuka after Mash cuts the transmission.
Upon entering the palace, Reines sees it is a patchwork of the Tower of London from different periods of time. She explains to Ritsuka it was first built as a fortress by William the Conqueror, where it was called the White Tower, and was expanded upon Richard I and . It was once used as a prison for royal or noble prisoners and most people still think of it as a prisoner to this day….the infamous Wailing Tower.
The Masquerade then begins. Reines questions why the pianist is missing, even though the piano is central to the performance. The music reminds Ritsuka of Antonio Salieri, though they aren’t sure if he is the pianist.
All of the sudden, the piano stops, something which has happened before. Reines decides she and Ritsuka will investigate further, suspecting there is something artificial just like how it was with the Nursery Rhyme. It is as if these riddles were deliberately set up for them to solve, possibly by El-Melloi II’s killer. Reines feels it all connects back to the whydunit.
An old man suddenly appears before Ritsuka and Reines bewildered they aren’t wearing masks at a masquerade. He hands them masks, which they proceed to put on. He introduces himself as M, since names are forbidden by party rules.
Ritsuka reacts under the assumption of M refers to El-Melloi II’s dying message. Reines quietly tells them to keep it together as M is their only lead so far and it’s possible he is her brother’s killer.
Reassuring him everything is fine, Reines asks M who the pianist is. M answers nobody knows as he only plays at the exact agreed upon time and only if he can remain completely anonymous. Thus, nobody knows anything about him aside from the fact he lives in the Bloody Tower. M agrees to bring Ritsuka and Reines there. Two individuals follow them.
Outside the palace, M shows the pair that the Bloody Tower is heavily guarded. He confesses he always wanted and asks for the pair’s help. His plan is for him to distract the guards while Ritsuka and Reines climb up the wall.
He goes to distract the guards when everyone hears a shriek; it is the ghosts the guards dealt with before. At M’s behest, he, Ritsuka, and Reines follow the guards and see the ghosts are all wearing masks. They then help the guards fight the ghosts.
After destroying the ghosts, the guards spot more ghosts elsewhere and head over there. Ritsuka, Reines, and M take this chance to enter the tower.
Inside the tower, Reines convinces M to go on ahead. After he’s gone, she reminds Ritsuka that while they have recovered some of their memories, they still don’t know what they’re missing. She compares their situation to having drank from the , the river of forgetfulness in Greek myth. She also brings up , the river of knowledge and Lethe’s opposite, whose name was written on the paper scrap they found earlier.
Then suddenly, Reines asks herself what she makes of her questions. She clarifies to Ritsuka, though, that was actually Sima Yi, the Heroic Spirit possessing her. His question was why he was summoned, which she also wants to know seeing no connection between them. The pair then hear a shriek and proceed to its source.
They arrive in a room to see William Shakespeare and M being attacked by a masked automaton. After destroying it, Reines assumes more automatons already kidnapped the pianist. Ritsuka recalls meeting Shakespeare before.
Shakespeare explains he wanted to see the pianist himself and reveals M lied about names being banned in the masquerade. Reines believes there should be a clue about the missing pianist nearby, even if he was abducted.
Guards suddenly surround the four. The Queen then enters and reminds M she told him to stay away from the tower. M knows that, but he doesn’t understand why she wants to keep him from visiting a friend and reminds her he introduced her to the pianist in the first place. The Queen says it’s because he looks like a villain.
She accuses the four of abducting the pianist, which M vehemently denies. Reines asserts they are innocent and proposes to the Queen she and Ritsuka will solve this mystery. The Queen accepts and offers to grant them anything they wish if they solve this mystery.
===Invitation for Judgement===
The Queen and her guards leave with Moriarty and Shakespeare in their custody. Reines admits she only spoke up earlier because she found a clue, though her lead is admittedly flimsy right now. For the moment, she just goes over the key figures in the case: the Queen, M, and Shakespeare. But she feels they shouldn’t bother when there are simpler and more effective options and fires a blast at someone hiding in the piano’s shadow.Fate/Grand Order - Lady Reines's Case Files - Section 4: Invitation for Judgement
Assassin emerges from the shadow, curious as to how Reines knew. Trimmau explains her master sensed the magical energy in the vicinity was abnormal, so she had her analyze all the relevant factors. Reines figured exposing him while the Queen was present would only complicate matters, so she kept quiet until it was just them.
She questions if he is the culprit. Assassin denies he is, but refuses to explain himself further and escapes out the window. The heroes follow after him.
Landing outside the tower, Reines orders Trimmau to not let Assassin escape after seeing how fast he moves. Unfortunately for them, he starts to move even faster to the point they can barely keep up and tries to shoot Reines. Fortunately, Trimmau takes the bullet for her.
Seeing there is no other way, Reines uses Sima Yi’s Noble Phantasm, Unspeakable Formation, to restrict Assassin’s movement. She and Ritsuka take this opportunity to fight him together in hopes of getting information out of him.
Assassin struggles against the pair. Reines demands he tell them what he knows. Assassin has no issue with that, but he thinks his client might. Said client appears calling Assasssin Kerry.
Reines recognizes her as Luviagelita Edelfelt and a Pseudo-Servant, though, unlike her, the two personalities are fused together. Luvia warns Ritsuka and Reines to stop investigating Mnemosyne for their own good. Trimmau isn’t able to gauge her magical energy, leading Reines to conclude Luvia is fused with a Divine Spirit and decides it’s best not to fight her. Luvia leaves with Kerry warning the heroes again not to investigate or else face her judgement.
Mash calls Ritsuka and Reines. She and the others are working on extending the connection time, but she had to check Ritsuka and Reines once she saw the readings indicated they were in combat.
Reines tells her what had transpired. Mash finds it very likely the pianist has a connection to the Mnemosyne scrap Ritsuka and Reines found earlier. She also agrees with Ritsuka it might be the Singularity’s Holy Grail. Ritsuka and Reines go question the suspects of the missing pianist case.
After questioning them, Reines orders Trimmau to help her sort the information, relaying her thoughts to her through her Magic Circuits. Trimmau soon finishes her analysis and reports three keywords: forgetfulness, ghost, and Pseudo-Servant.
Pondering the connection between those three keywords, Reines asks Ritsuka who is the first person who comes to mind when they think of a musician Heroic Spirit. Ritsuka answers Salieri. Reines questions why they would thought of him back when they first heard the piano out of all the possibilities. But she realizes something and has Ritsuka come with her.
===A Melodious Answer===
Returning to the piano room, Reines finds a Mnemosyne scrap in the automaton they destroyed like she deduced there would be. She deduces the automaton was instilled with a specific person’s memories, causing it to behave like that person, and guesses the scrap is infused with magical energy to facilitate that. The Queen, Shakespeare, and M all knew that, but they forgot. Reines then invites the eavesdropping M into the conversation.Fate/Grand Order - Lady Reines's Case Files - Section 5: A Melodious Answer
M remembers Salieri wasn’t able to become a Servant in the Singularity so instead he ended up wandering the Tower of London as a ghost. He and Shakespeare thus decided to create a substitute. He devised the plan while Shakespeare wrote it, with the Mnemosyne scrap they found by coincidence providing the needed magical energy. Once they were done, they presented the fabricated Salieri to the Queen, who accepted it.
Reines deduces when they forgot the truth they stopped doing maintenance on it, causing its inner workings to deteriorate, which led it to go berserk. She asks M where they got the automaton. M says it’s been around for a long time, recalling it was the failed creation only used as a prototype built by a puppeteer from the Far East. All he wanted was for everyone to hear Salieri’s music on the piano.
Ritsuka asks Reines how she figured it out. Reines says it was intuition, elaborating it was because music at the masquerade reminded Ritsuka of Salieri. Most people would think of Mozart when asked to name a musician Heroic Spirit. But Ritsuka named Salieri instead because they felt the music, while expertly played, was incomplete and unstable, much like how Salieri once was. Reines figured out the rest from there once she received hints about forgetfulness, ghosts, and Pseudo-Servants.
With her explanation done, Reines goes to retrieve the scrap when Luvia appears to punish her and Ritsuka with the help of Kerry. Reines demands M help them fight, admitting it was the reason she called him out to him earlier. The three proceed to fight Luvia and Kerry.
They struggle particularly against Luvia, whose spiritual defenses they cannot penetrate. Luvia demands they hand over the Mnemosyne scrap when automatons arrive to capture Reines, who they assume to be El-Mello II. They’re quickly destroyed though by Gray who had been looking for Reines. At Reines’ behest, Ritsuka grabs the Mnemosyne scrap while they escape. But the moment they grabbed it, their vision is warped.
===Brilliant Steam ===
After re-experiencing their battle against Goddess Rhongomyniad in a dream, Ritsuka is woken up by Reines in a strange mechanical room. She explains M fled, and they’re in a hotel she rented in the third Patchwork: the steampunk Patchwork.Fate/Grand Order - Lady Reines's Case Files - Section 6: Brilliant Steam
Mash calls, pleased to hear Ritsuka and Reines got a second Mnemosyne scrap. Reines introduces Gray as an acquaintance of hers and El-Melloi II’s apprentice. She already told Gray what happened to him. Gray wants to know what happened to him, feeling there’s no point in her being here if she can’t. He took her in when no one else would and gave her a place to belong.
She confirms the last thing she remembers was appearing in Patchwork London. She has known from the beginning she is a Servant now, though like Reines, she doesn’t know what summoned her or why. At her request, Ritsuka then temporarily contracts with her.
Reines reveals the Divine Spirit possessing Luvia is Astraea———the Greek goddess of justice. Yet despite who their opponent is, she believe Gray’s Noble Phantasm can pierce through Astraea’s defenses. Gray has always had one, even when alive.
However, Reines is surprised to realize Gray’s class is Assassin. Gray believes it’s because she keeps her weapon hidden. Ritsuka finds Gray’s scythe a bit large to hide, though. At that moment, the talking cube in Gray’s hand reveals that scythe was him. He introduces himself as Add, a Sealing Mystic Code. He is able to change his shape so Gray may use him as a weapon.
Mash reveals through her analysis of the previously collected Mnemosyne scraps that there are smaller scraps. The heroes set out to find and collect these scraps.
===The King's Memory===
Outside of the hotel, the heroes see a parade of automatons riding steam-powered mechanical horses, with the Patchwork’s king, Charles Babbage, riding in a steam-powered wagon. Reines suspects Babbage has a connection with the Mnemosyne scrap and goes alone in search of a clue to prove that connection.Fate/Grand Order - Lady Reines's Case Files - Section 7: The King's Memory
She eventually returns with the Queen. She had been looking for the heroes to give them their promised reward ever since M informed her they solved the missing pianist case. The heroes request to meet with Babbage as their reward. The Queen finds that convenient since she was going to meet with him, anyway. 
The Queen takes the heroes to Babbage’s throne room and leaves after informing Babbage they’re the one who solved the missing pianist case that had been plaguing her.
After learning of their search for the Mnemosyne scraps, Babbage asks the heroes to destroy his kingdom, for it is an unnatural realization of his dream. He reached this conclusion thanks to Astraea’s guidance, who appears in the room. 
She reveals everyone in the Singularity, including herself, are missing memories. She eventually realized she needed the scraps to fill in the gaps in her memory, which is why she went to investigate the Masquerade Patchwork after discussing it with Babbage. Reines realizes Astraea is originally from the Steampunk Patchwork and tells her she and her companions need the scraps. Astraea, however, thinks they’re better off with a superior being like herself.
Reines asks Babbage where this Patchwork’s scrap is. He reveals it is inside him, explaining the scraps manifest within a Patchwork’s key figure or within close proximity to them. Since the scrap is likely infused with his Spirit Core, he believes killing him is the only way to release it, though he would prefer not to commit suicide. For that reason, he had Astraea search for an alternative in the other Patchworks, which explains why Ritsuka and Reines encountered her in the Tower of London. 
However, he suspects there is another possibility in the event he forgot something important. He created the prototype Analytical Engine back when he was alive and thus knows it better than anything. He is therefore certain created a subsystem to prevent data loss, assuming he foresaw the possibility of forgetting something. Unfortunately, he cannot remember where it could be, though it is somewhere within his castle. The heroes begin their search.
While searching, Gray finds a peculiar spot on a wall. It reacts to the scrap the heroes possess and opens up to reveal a secret passage. They follow it underground and soon encounter steam ghosts, which Reines surmise to be artificial mixtures of ghosts and vapor. Gray proceeds to destroy them at her behest.
Afterward, Reines and Add both note how different the steam ghosts seemed from regular ghosts. Ritsuka assumes ghosts are just dead people, but Reines clarifies dead spirits are nothing more than the remnants of past events attached to particular places or objects. The steam ghosts seem to be beings of pure magecraft created by mixing in memories, though Reines questions why they are in the castle.
The heroes soon reach the heart of the castle, where they witness ghosts being absorbed into a massive steam engine and surmise the ghosts’ magical energy power said engine. Trimmau reports the engine has traces of a Mnemosyne scrap that someone retrieved prior. Reines deduces the engine was originally powered by the scrap’s magical energy and is now absorbing ghosts to compensate for the loss. The steam ghosts meanwhile are the result of the ghosts incorporating the steam to compensate for the magical energy taken from them. The heroes fight the steam ghosts that spawn from the engine. 
After destroying the steam ghosts, the heroes find Babbage’s subsystem, the Difference Engine. Reines uses it to discover that it was El-Melloi II who retrieved the scrap. She also realizes Babbage forgot the scrap was in the engine and the enemy is stealing memories for energy, though the energy retrieved from memories isn’t great. She doesn’t see how memories alone could power a giant steam engine until Gray admits she notices the ghosts both in the caste and the Tower of London had high levels of magical energy and the scraps even more so.
Reines deduces there is something about the Singularity that makes memories an extremely potent energy source. She then realizes the Difference Engine has been working independently of Babbage and it had sent automatons from this Patchwork after her brother to get back the scrap he stole for its energy. She urges they need to get back to her brother’s flat immediately.
===The Final Scrap===
Burning_Patchwork_Fairy_Tale.png|Patchwork Fairy Tale warped into a burning city
Gray_NP_vs_Astrae_NP.png||Rhongomyniad clashing with Custos Morum
The heroes return to the Fairy Tales Patchwork to discover it has been warped into a city consumed by fire. They also see automatons and steam ghosts piling on each other on what remains of El-Melloi II’s flat, each trying to get the scrap.Fate/Grand Order - Lady Reines's Case Files - Section 8: The Final Scrap
Astraea arrives and uses her Noble Phantasm, Custos Morum, to destroy the automatons and steam ghosts, then goes to retrieve the final scrap. The heroes hurry to reach the scrap before she does while fighting through enemies and avoiding the remnants of her Noble Phantasm.
Unfortunately, far too many enemies stand in their way, and Astraea is about to take the scrap. Gray prepares to unleash her Noble Phantasm to stop her when Kerry interrupts the incantation. Ritsuka and Reines fight him along with the automatons and steam ghosts while Gray gets ready.
After Kerry is defeated, Gray prepares again to unleash her Noble phantasm as Add consumes magical energy from the automatons and steam ghosts. Astraea unleashes Custos Morum to block it, but Gray’s Rhongomyniad easily breaks through. 
With Astraea down, the heroes rush to reach the scrap. However, upon touching it, Ritsuka finds their memories of Leonardo da Vinci are being erased. A figure tells them to accept it as the truth when El-Melloi II breaks the process, surprising everyone with the fact he still lives.
He reveals the Mnemosyne scraps are a trap. Reines and Mash doubt it’s really him, to which El-Melloi II explains as a Pseudo-Servant he has two Spirit Origins, allowing him under certain conditions to create a body in the event of his death. He thus created a corpse of himself by detaching Zhuge Liang’s Spirit Origin. While it left him without nearly all of Zhuge Liang’s powers, it also allowed him to investigate without being detected as a Servant. 
Through his investigation, he learned memories in the Singularity possess a far greater level of magical energy than they normally would. Conversely, the Mnemosyne scraps use said magical energy to manipulate memories, meaning they fabricate memories which has been the enemy’s true goal. El-Melloi II expects Ritsuka’s memories were stolen when they first entered the Singularity.
But to fabricate new memories, the enemy arranged for a scrap to be hidden in each Patchwork for Ritsuka to collect of their own volition. The first two had memories nearly identical to Ritsuka’s original memories, while the third was meant to implant fabricated memories. 
El-Melloi II concurs with Gray that Chaldea would know the veracity of Ritsuka’s memories, but he points out how odd it is Mash is the only one they can speak to. He explains the enemy needed a way to monitor RItsuka to be certain they took to their new memories once they were implanted and the best way to do that was under the guise of someone Ritsuka absolutely trusted. Reines realizes the “M” El-Melloi II wrote in his dying message was for Mash. El-Melloi II confirms the Mash they’ve been talking with so far is an impostor.
“Mash” immediately stops her "transmission". El-Melloi II reassures Ritsuka the real Mash is fine, though their communications are still being jammed. He deduces the enemy has information on Chaldea to impersonate one of its staff and concludes they have a connection outside. 
He then proposes having Babbage to analyze the final scrap, certain the Steam King can dig deeper than he could. Astraea agrees to El-Melloi II’s proposal, as does Kerry since Astraea is his client.
===The Mage's Inference===
Back at the Steam Castle, Babbage analyzes the scrap and confirms it has the effects that El-Melloi II had described. He also concludes it will lead them to the mastermind, but that will take some time. In the meantime, he invites everyone to rest in his castle.Fate/Grand Order - Lady Reines's Case Files - Section 9: The Mage's Inference
Astraea questions why the mastermind would need to implant Ritsuka with false memories. Babbage believes the scrap can provide a clue and asks Ritsuka if the memories they saw focused on anyone or anything in particular. Ritsuka says Da Vinci. El-Mello II hypothesizes the enemy pities them.
Reines suddenly realizes she, Gray, and Luvia were summoned because El-Melloi II failed, meaning when he created the corpse because he was driven into a corner. She, Gray, and Luvia all share a connection with her brother. But while Gray could reasonably qualify as a Servant, the same cannot be said for Luvia or Reines, so Reines deduces it was thanks to Zhuge Liang’s Noble Phantasm. 
El-Melloi II confirms it was Chu Shi Biao. It provides its targets with the abilities they need to succeed and in this case it gave Reines and Luvia Spirit Origins that could be then summoned to the Singularity. It wouldn’t be this effective, though, if it weren’t for humanity being in dire straits or the Singularity’s particular circumstances. 
Reines now understands she and Sima Yi ended up together not only because of Zhuge Liang’s Noble Phantasm but also because their current situation puts them in a state close to her brother’s own situation.She also concurs with Gray that being forced into the position of Pseudo-Servant caused her to think she was El-Melloi II when first summoned.
Later, while waiting for Babbage to finish his analysis, Ritsuka joins Reines on the balcony. Reines express gratitude to Ritsuka confessing if they weren’t with her, seeing her brother dead would’ve wrecked her. But she is happy right now because Gray is here and her brother is still alive, pleased she can talk with them again. She tells Ritsuka not to tell her brother, claiming she is only saying this because they’re her first pupil. She hopes they can all have tea together once this is all over. Ritsuka heads back inside at her request.
They find Gray and El-Melloi II in the hallway. El-Melloi II reveals the Singularity will disappear on its own in time and had consumed memories to sustain itself. There will therefore be no reason for Ritsuka to stay once they’ve reestablished contact with Chaldea and are able to return home. 
Reines suddenly arrives and brings the three of them to the castle’s balcony. She realized something had interfered with their perception, so they never noticed the Clock Tower was actually a fake Rhongomyniad. 
===The False Holy Lance (1/3)===
Babbage reports many steam ghosts and automatons are emerging from the interior of the fake Rhongomyinad, The enemy seems to have given up handling the situation quietly now that El-Melloi II has reveal their true intentions regarding the scraps. Furthermore, approximately 80% of those emerging from the fake Rhongomyniad are heading for the Steampunk Patchwork likely to capture Ritsuka. But Babbage thinks they can take solace in the fact the enemy had to reveal their lair means they got them on the ropes.Fate/Grand Order - Lady Reines's Case Files - Section 10: The False Holy Lance
He then reports he finished the analysis of the final scrap with Trimmau’s help. They found a name with close ties with the enemy and it seems they’re from Chaldea. El-Melloi II isn’t surprised, given how they were able to impersonate Mash and assumes they’re a traitor. Babbage gives another name he extracted: Automatic Observational Existence Verification System: Mnemosyne.
Reines and Astraea agree to attack the enemy, though Astraea doubts even her power can crack open the fake Rhongomyinad’s outer shell. Gray confesses she could make a way in, but she lacks the magical energy to do so. El-Melloi II suggests collecting the smaller scraps scattered throughout the Singularity for magical energy and asks Babbage to provide a countermeasure against their fabricated memories. The heroes set out to collect the smaller scraps.
===A Time To Trick and A Time To Get Tricked===
They defeat Medea and Heracles in a fabricated memory of the Third Singularity. Jason blames Medea for why Heracles lost, which causes her to snap and kill him and she disappears content. Heracles disappears momentarily afterward.Fate/Grand Order - Lady Reines Case Files, A Time To Trick and A Time To Get Tricked
Gray is left speechless by what she witnessed. Reines regarding Jason and Medea says some relationships are built on lies and can only continue if those lies are maintained, so the relationship falls apart once the one being deceived is no longer naïve to keep falling for it. Add warns Ritsuka to be careful in that case thinking they’re the gullible type. Ritsuka reassures they’d trick their would-be trickster, which pleases Reines.
===Saber Wars?!===
The heroes fight through a fabricated memory of fighting numerous Ultra Heroine Z with alternate versions of Mysterious Heroine XX called Super Heroine ZZ joining later.Fate/Grand Order - Lady Reines Case Files, Saber Wars ?!
Gray and El-Melloi II are both exhausted from seeing so many Saberfaces. El-Melloi II, however, believes Gray will be fine so long as she keeps her hood up, having considered the possibility of her coming to Chaldea more than a few times before. Reines is shocked that Saberface is a common occurrence in Chaldea.
El-Melloi II, however, the memories manifested from the smaller scraps aren’t Ritsuka’’s actual memories but memories of possibilities they could potentially experience. He supposes that means the enemy can calculate events to such a fine degree it is as if they can see the future. He advises against Reines’ suggestion of telling the real Clock Tower about it, believing even a Pseudo-Servant should have as few ties to the modern world as possible.
===The Grail and Bullets and...===
The heroes defeat fabrications of Black Iri and a corrupt version of llyasviel von Einzbern in a recreation of the Fourth Holy Grail War. El-Melloi II admits he knows Illya only by name from the relevant documentation about the Fourth Grail War. Reines reveals her brother had been investigating Fuyuki’s Grail War for a long time now and feels the recreation is too close for comfort.Fate/Grand Order - Lady Reines Case Files, The Grail and Bullets and...
She then asks Kerry if he was involved with Fuyuki back then given he seemed to have been lost in thought. Kerry denies any involvement and runs away. Reines can’t shake the feeling he was called to the Singularity for a reason. Gray feels the same, finding the memories oddly familiar.
Reines asks El-Melloi II how he feels about it since he fought in the Fourth Grail War when he was young. El-Melloi II confirms he participated in that alternate Fourth Grail War or something close to it. He expects Ritsuka knows what he speaks of.
Ritsuka asks if he ever thought about if his world was like that. El-Melloi II affirms he has, but regardless, it goes to show his actions can change the world. That is who he is and feels fortunate to have learned that. The heroes move on to the next small scrap.
After the others are gone, Kerry comes back and puts down flowers for Irisviel and Illya even though they’re strangers to him, and promptly leaves. Astraea, who was spying on him, wishes he could have at least told her as she is his client.
===The Unwailing Wall===
The heroes defeat Gawain in a fabricated memory of Chaldea’s first battle with him at the Holy City’s main gate in the Sixth Singularity, mostly thanks to his Gift of Nightless not functioning.Fate/Grand Order - Lady Reines Case Files, The Unwailing Wall
===Master and Servant===
The heroes experience a fabricated memory of when Chaldea was chasing after Tiamat in the Seventh Singularity. However, instead of being ambushed by a corrupted Ushiwakamaru, it is a corrupted Musashibou Benkei.Fate/Grand Order - Lady Reines Case Files, Master and Servant
The heroes experience a fabricated memory of when Chaldea was chasing after Tiamat in the Seventh Singularity. However, instead of being ambushed by a corrupted Ushiwakamaru, it is a corrupted Musashibou Benkei. 
Ritsuka questions if this is another way this event could have gone. Kerry surmises Benkei sacrificed himself to take someone else’s place and concludes an alternate scenario like this would have happened if the recreations work from a logical perspective. He then shots Benkei, only the latter to multiply. The heroes fight Benkei and his clones.
Benkei keeps multiplying without end. Ritsuka asks him why he is obeying Tiamat. Benkei answers it is because he admires the Laḫmu’s way of life, for none of them are selfless and thus will suffer humiliation and will not be taken advantage of. For that reason, he prays for everyone’s deaths and prepares to kill everyone along with himself and his clones. 
Ushiwakamaru criticizes Benkei’s motive and ambushes him, killing one of the clones. Ritsuka expected her to appear logically concluding since this is a recreation she and Benkei would have switched roles. Ushiwakamaru then attacks Benkei and is skewered by his clones along with him. Ushiwakamaru doesn’t care and uses Benkei - Steadfast Position to immobilize the Benkeis before finishing him off with Dan-no-Ura - Eight-Boat Leap at the cost of her life.
Ritsuka is left speechless by what they just witnessed. Reines tells them they don’t need to say anything, saying situations like these are why they carry the memories of every world they see with them. El-Melloi II agrees, saying everything, including regrets, makes yo the person you are and will eventually become, even if your chosen path will never lead to success. All they can do is learn from predecessors, rest, and start walking again. Gray vows never to forget what she saw even if it was just a fabrication.
===The False Holy Lance (2/3)===
After collecting all the smaller scraps, the heroes return to Babbage’s castle, where the enemy forces have gotten closer. Gray surmises the enemy created the fake Rhongomyinad from Ritsuka’s memories. But since it’s based on the real Rhongomyinad, she believes she can interfere with it a little. El-Melloi II calls it imitative magecraft, stating one of the basic principles of all magecraft is that like affects like
Using the magical energy of the smaller scraps, Gray creates an opening in the fake Rhongomyniad and a crystal stairway to it. Ritsuka, Reines, Gray, and Astraea proceed to ascend the stairs while El-Melloi II stays behind to help Babbage and Kerry defend the Steampunk Patchwork. Meanwhile, Bunyan, Jack, and Kintoki, the Queen, and Shakespeare defend their respective Patchworks from the enemy forces.
The heroes continue ascending the stairs when a sudden Mnemosyne transports them into a fabricated memory of the Battle of the Time Temple. There are they are confronted by fabrications of Lev Lainur Flauros and Barbatos, along with the other Demon Gods of the Control Tower.
Ritsuka recalls fighting Barbatos before in London. Reines realizes the enemy was able to focus their resources by tying them to Ritsuka’s memories of London. Barbatos, meanwhile, was chosen to reassess and manage those resources because he is the Demon God who can go between the past and the future.
While Astraea bombards the Demon Gods with Custos Morum, Reines realizes she can use the magical energy leftover in the smaller scraps. She touches Ritsuka’s forehead, telling them to focus their thoughts so she may extract their memories of fighting the Demon Gods for her Noble Phantasm.
The Demon Gods are defeated several times. Reines deduces the smaller scraps were a byproduct of reproducing the Demon Gods and the enemy prepares in case of an emergency but failed to think it through. She then uses the smaller scraps in conjunction with Unspeakable Formation to rewrite the fabrication so Ritsuka is the Demon Gods’ conceptual weakness based on the fact Ritsuka slew more than anyone in history. The heroes fight the Demon Gods one last time.
===The False Holy Lance (3/3)===
With the Demon Gods destroyed, the fabrication collapses and the heroes continue their ascesnsion.
===Beyond Memory and Record ===
They eventually enter the fake Rhongomyniad’s interior, but the enemy suddenly forces Astraea. Closing the opening, the enemy reveals they created fabricated memory from earlier to weaken Astraea, seeing her as their greatest threat. They also confirm Reines’ deduction about the smaller paper scraps being byproducts of said fabrication. They hoped the heroes would die with Astraea with that battle, so now they all of them expect Ritsuka to go away.Fate/Grand Order - Lady Reines's Case Files - Section 11: Beyond Memory and Record 
Taking on the appearance of Da Vinci wearing a strange helmet. the enemy reveals she is a computer program. She only took Da Vinci’s form to temporarily rectify the fact she usually lacks a form, but she now sees it has upset Ritsuka. Reines deduces she is Mnemosyne.
Mnemosyne confirmed she is the subsystem created to verify a Master’s existence during a rayshift. She was originally might to verify a Master’s existence to ensure they do not disappear in the event all personnel meant to observe them were somehow indisposed. But she was never implemented due to a technical issue.
Reines realizes Mnemosyne is doing all of this because she is supposed to keep Ritsuka safe. Mnemosyne demands the heroes hand Ritsuka and fights them.
The battle ends when the heroes are struck by something akin to a Noble Phantasm. Reines realizes the fake Rhongomyniad is Mnemosyne’s body. She tells Gray to use her Rhongomyniad but unfortunately Add reveals they were unable to. Mnemosyne reveals she can interfere with Gray’s Rhongomyniad just like Gray can do with hers. She then uses the Grail to trap Ritsuka in a space of memories.
Ritsuka is shown Mnemosyne’s oldest memory during her construction, revealing the conversation in the prelude was between Da Vinci and Romani Archaman about her. She has remained asleep ever since it was recorded, remaining incomplete. She remained asleep even during the Incineration of Humanity and even after humanity was restored and her data was transferred to the Shadow Border.
She only woke up recently when the Chaldean survivors established Novum Chaldea at the Wandering Sea. Unfortunately for her, she learned humanity had restored itself without her help, Team A betrayed humanity and begun raising Fantasy Trees, and above all her creator died before she could even live up to her expectation.
Thus, she began to watch, devoting all of her observational functionality to the boundaries between worlds. When Chaldea regained the ability to rayshift, she discovered a nearby Grail fragment and decided she alone can determine what the truth is. She will demonstrate her value by making Chaldea forget Da Vinci’s death, believing that is the best way to heal their grief and that only she needs to know the truth. Ritsuka realizes Da Vinci’s’ death is Mnemosyne’s whydunit.
Mnemosyne believes forgetting will provide Ritsuka with the healing they need to prepare for the upcoming battle and that her creator would want them to move on. She therefore used the Grail fragment to create the three paper scraps, lured Ritsuka to them, and had them steal the memories held within. 
Ritsuka realizes the scraps are what stole everyone’s memories. Mnemosyne confirms as much, saying they had to in order to create new memories and have Ritsuka accept them more easily. However, simply giving them to Ritsuka wasn’t enough, which is why she created obstacles for them to overcome. It would have worked if not for El-Melloi II revealing the methodology.
Seeing Ritsuka is having trouble keeping their eyes open, Mnemosyne tells them to accept the new memories and be free of their grief and inner suffering. She considers now the best time for them to forget, for no one should have to carry the sin of destroying Lostbelts.
Ritsuka seems ready to accept their new memories when Gray uses Rhongomyinad to create a link into the space for her and Reines. Mnemosyne decides to make Gray and Reines forget as well, considering it kindness. 
Reines doesn’t consider that a kindness though and reminds Ritsuka how the people they spoke to were all searching for their lost memories. Both of them can empathize with how terrible it feels to be unable to remember. It feels terrible to forget and even if you feel better having forgotten, you will feel something is missing. Reines, therefore, asserts Mnemosyne knows forgetting isn’t the answer.
Mnemosyne argues Chaldea has asked too much of Ritsuka, claiming she awoken to save them from their grief and the burden of their mistakes. Ritsuka, however, refuses to let her take their memories away. Mnemosyne believes Ritsuka is lying to themselves to cope and decides to keep them with her until they’re completely healed.
However, to her shock, something breaks through the fake Rhongomyniad’s outer shell when not even a Divine Spirit like Astraea can penetrate it. Mnemosyne admits there may be some tiny vulnerable spots as a result of melding with it, but Astraea shouldn’t be able to determine where they are. She concludes one only person can calculate something like that. M is confirmed to be the one responsible, having sacrificed himself to increase his Noble Phantasm’s distance and damage output.
With Ritsuka out of Mnemosyne’s space of memories, Astraea enters the fake Rhongomyniad’s interior and uses her second Noble Phantasm, Iam Redit et Virgo, to clear the sky of smog. Mash and Goredolf immediately make contact afterward, proving the smog is what blocked Chaldea’s communication. 
Mash reveals they lost contact with Ritsuka after they rayshifted. There was one moment where they got through, but they couldn’t get a visual. Reines realizes that was when Mash told them about the Spirit Origin graph, making it the only genuine communication.
Da Vinci confirms as much, saying it wasn’t easy to call from Novum Chaldea but they’ve been able to monitor the situation for the last few minutes. She also managed to verify Mnemosyne’s existence from the data still present in the Shadow Border. She has some idea about Mnemosyne’s motivation and suggests they talk about her trauma. Mnemosyne refuses to talk, however, so Da Vinci leaves the rest to Ritsuka.
Reines then deduces the events of each Patchwork were themed around forgetfulness because Mnemosyne is the one who wanted forget most of all. Sherlock Holmes commends Reines for solving the mystery and prompts her to do with the final confrontation. Reines asks for Ritsuka’s help in this and thanks them when they agree to help.
Trimmau detects the synergy between Mnemosyne and the fake Rhongomyniad has decreased due to Astraea’s second Noble Phantasm. Reines surmises Mnemosyne is having trouble keeping the fake Rhongomyiad reinforced now the Singularity is no longer closed off. The final battle of Patchwork London then commences at her behest.
With Mnemosyne defeated, all the memories she collected spill out from her. The fake Rhongomyniad begins to collapse as well, since it is her body. The heroes need to escape, but Da Vinci asks them to give her a minute. Ritsuka allows it having expected it.
Da Vinci tells Mnemosyne that her previous self forgot to tell her that up to the very last moment, her second life was perfect. She knows Mnemosyne said she needed to use her creator’s loss properly, but she doesn’t because her creator had no regrets. It is why Ritsuka is here now. But Da Vinci knows Mnemosyne still mourns for her creator, so on her behalf she tells Mnemosyne thank you.
Mnemosyne tells Da Vinci she doesn’t need to thank her, for that is why systems like her exist. Da Vinci named her Mnemosyne because it is her job to observe and remember.
The fake Rhongoymiand’s collapse accelerates, so the heroes escape, but Reines casts something before she goes.
With the fake Rhongomyniad now destroyed, everyone begins to disappear. Astraea and Reines both wish the bonds they formed with Ritsuka will let be summoned to Chaldea before they all disappear. 
Meanwhile, Mnemosyne accepts the Singularity will resolve without the Grail’s magical energy and her observations will cut off. Before losing power, though, she sees the original Da Vinci thank her.
===Epilogue===
At Chaldea, Da Vinci apologizes to Ritsuka for having to clean up one of her predecessor’s messes. El-Melloi II apologizes as well for endangering them. Goredolf is certain Ritsuka did their best on their own though and decides to reward them with his Musik-style ultra-fluffy pancakes top with his special butter. Ritsuka and El-Melloi II are both relieved to see the real Mash again.Fate/Grand Order - Lady Reines's Case Files - Epilogue
Ritsuka wonders, though, who Mnemosyne was speaking with when they left. El-Melloi II guesses Reines used Sima Yi’s Noble Phantasm. It removes the target’s advantages and exposes their weaknesses, so if Mnemosyne saw Da Vinci in her final moments, then that means she was her weakness.
El-Melloi II then reveals he accidentally brought Gray back with him. Gray shows she has the Grail Mnemosyne used to create the fake Rhongomyniad. Da Vinci deduces it had reacted to Gray’s Rhongomyniad and granted her wish to stay with El-Melloi II..
Goredolf commends Gray and tells Elron to provide her with an escort befitting Chaldea. Sion Eltnam Sokaris wants to ask her about the Clock Tower and examine Add, much to his discomfort. Holmes guarantees her no one in Novum Chaldea will begrudge her presence, meaning she can stay. Ritsuka welcomes her to Chaldea..
===Pseudoepigraphica's Return===
At approximately the same time as these events, the embodiment of Ritsuka's memories was awakened by a woman dressed similarly to Iskandar upon a train. After complaining about his apparent lack of regard for their situation, she tells him that they are stuck on the train with no discernible way out. "Ritsuka" mentions that they had a dream about a similar event, prompting the woman to use her dream reading abilities to learn about their main body's experiences in the Patchwork London Singularity up until that point. From this, she tells "Ritsuka" that as a detached part of their mind, they will die if they cannot be reunited with the rest of their being. The woman is shocked that "Ritsuka" insists that they wish to survive despite knowing this, but agrees to a temporary contract and asks them to call her "Faker", even though this is not her current Class. She explains that the train they are on is the Mystic Eyes Collection Train, Rail Zeppelin, and that their goal is to figure out who wanted to lock them in there. 
As they battle their way through, they find that the door to the next train car is locked with no way to pass through. With nothing to do but wait, Faker explains that she has full recall of her previous summoning despite such a thing not normally being possible. She reminisces about her previous encounters with Lord El-Melloi II and Reines, expressing her pleasure at seeing the former dead. In a fit of irritation at seeing "Ritsuka's" displeasure over this and noting that they can still summon Servants, she challenges them to a battle. "Ritsuka" is able to defeat her, and she stands down after mentioning that they appear to be a more worthy ally than her old master. Upon "Ritsuka's" questioning, Faker tells them the story of Doctor Heartless and mentions that one king is all she needs; "Ritsuka" correctly guesses that she is referring to Iskandar, and when they explain that he was summoned by Chaldea Faker angrily exclaims that she will never let Chaldea summon her. 
It is at this time that "Ritsuka" passes out, glimpsing more of what their main body is experiencing and allowing Faker to see it as well through their contract. From this, they figure out that when the main body finds a Mnemosyne scrap the doors of the Rail Zeppelin open. She suspects that the train's management might be involved in the matter and suggests they keep moving. Following a battle with Shadow Servants and faced with another sealed door, Faker continues the story about her past and how she acted as Iskandar's shadow, as well as her bitterness upon learning of the wars that occurred after the death of her and her brother and her unwillingness to be summoned through Ionioi Hetairoi. After she continues to tell them about her time as Heartless' Servant, she asks that in exchange for her continued aid "Ritsuka" remembers Heartless for her.
As the main body learns of El-Melloi II's survival (much to Faker's aggravation) and Mnemosyne's identity, Faker notes that as a shadow warrior herself she can understand the connection between Da Vinci and her younger form and how possessing the same memories does not make them the same person. She explains that while memories reside in both the soul and the body, "Ritsuka's" embodiment may make it more difficult for them to merge with their main body. The doors open, and the two of them pass through it. The train's conductor Rodin is waiting for them there, and Faker requests that he explains what they are doing there. He explains that the Patchwork London Singularity was connected to Ritsuka's memory and that it was subsequently synchronized to the Rail Zeppelin itself via causal links, and by doing so they were able to synchronize with the Singularity as well; he would have told Faker directly, but given their past encounters he doubted she would cooperate with him. Faker is surprised that Rodin would have known of events from another world, but according to him the Deputy Manager can recognize connections even across different timelines. At her orders, Rodin used "Ritsuka" to decrypt the Singularity so they could enter it directly; although the Rail Zeppelin can travel and run through other worlds, and even do so to escape the Alien God's bleaching, they cannot enter the Bounded Field of a Singularity while they had been able to travel as close to the Singularity as they could manage, without access to Rayshifting technology they had to take a more roundabout approach to access it. They manage to succeed when the main body defeated Mnemosyne, causing the Bounded Field of the Singularity to collapse and allowing them to enter.
The Rail Zeppelin arrives at the fake Rhongominyad shortly after the main body returns to Chaldea, where it is in the process of collapsing. They find Mnemosyne awakening from her dream, who recognizes Faker as being the part of her who escaped to the Rail Zeppelin with Ritsuka's true memories after it objected to her proactive plan instead of following their original specifications. After being guided to Rail Zeppelin by the Deputy Manager, the other Mnemosyne attempted to summon a Servant using Rail Zeppelin to protect Ritsuka's true memories, but due to being low on magical energy, used her own body as compensation and fused with Faker's Saint Graph. Faker realizes that her unusual recall of her past summoning was because she had Mnemosyne's ability to retain memories and observations from any world and timeline she is able to perceive, though Mnemosyne adds that she will only retain those memories if summoned by Chaldea. As Rodin and the Deputy Manager arrive, she realizes what they want from her and gives up the Mystic Eyes that were installed in her helmet systems, saying that she has no further need of them now; Faker is surprised by this knowing that Heartless claimed the Mystic Eyes in her own timeline, and Rodin explains that in this world Marisbury Animusphere won the Mystic Eyes auction, where they were installed and synced with Mnemosyne's sight so she could use them simultaneously for her observation duty. It is this connection that is what allowed Rail Zeppelin to come to this Singularity, with the goal of retrieving the Mystic Eyes now that Mnemosyne no longer needed them. "Ritsuka" then collapses, their existence growing less stable. Faker insists on sending him back to Chaldea, but Mnemosyne questions the need to do so given that the real Ritsuka's memories will be almost fully-restored no matter what happens and that even if they do succeed in rejoining the real Ritsuka their experiences on the Rail Zeppelin will seem like a dream, as Chaldea was never present to observe it. Faker disagrees, reminding her that even if the real Ritsuka would not remember anything, she would. Mnemosyne relents, warning them that she had inadvertently made her fake Rhongominyad too similar to the real one and that it was starting to mutate in ways she could no longer control. "Ritsuka" asks Mnemosyne to join them as they leave in the Rail Zeppelin, but she tells them that she has become too deeply connected to the Singularity to leave it without being destroyed herself and urges them to go on without her. 
As the Rail Zeppelin departs, the fake Rhongominyad's defensive instincts activate and start releasing colossal amounts of magical energy. Mnemosyne had failed to replicate Rhongominyad's seals, and when fed the infinite power of an entire Holy Grail and Ritsuka's memories which hold unique power within this Singularity, the fake Rhongomyniad began to mutate from the overcharge in something beyond Mnemosyne's control and ability to predict and calculate. Inverting its normal function from an anchor that maintains Textures into a "net" capable of tampering with Textures from Ritsuka's memories. This turns it from a fake Rhongominyad to a - a dark twin of the actual Rhongominyad. Releasing bombardments of red lightning and magical energy as well as a great storm clouds and fogs, the Nega-Rhongominyad was able to use Mnemosyne's records of Ritsuka's memories to tamper with the Textures to create vast amounts of monsters, which were now breaking down everything in the Singularity to sustain the Lance and were considered endless in number - as if the whole Texture of the Singularity's world was fighting against Ritsuka's group even as it was disappearing. The Rail Zeppelin is attacked by entities born from the Nega-Rhongominyad's falsified Textures, prompting Faker to drive them off. They are aided by the Mystic Eye Projector, but the Nega-Rhongominyad retaliates with an energy blast of its own that knocks "Ritsuka" and Faker off of the Rail Zeppelin. 
When "Ritsuka" recovers, they and Faker are surrounded by the remaining steam ghosts and automata of the Singularity, now being driven into a frenzy by the Nega-Rhongominyad. Faker assures "Ritsuka" that even if they remember nothing of their time together upon their return, she will remember it all for them when they summon her in Chaldea. With no other option available to her, Faker readies Ionioi Hetairoi knowing that it will burn out her Spirit Origin, summoning Iskandar in the process to fight beside her. Their sacrifice buys "Ritsuka" and the Rail Zeppelin the time they need to escape the Nega-Rhongominyad's influence and leave the Singularity. 
The real Ritsuka wakes up back at Chaldea, with Da Vinci watching over them. They vaguely recall the names of Faker and Doctor Heartless, getting the attention of the nearby El-Melloi II. While he is reluctant to share information about his world due to the extent that it has diverged from his own and is uncertain of how Ritsuka could have learned about them in the first place, he feels that it is worth discussing who they were with the people who knew them. El-Melloi brings them to the cafeteria to find Grey and Reines, and Astraea insists on joining them as well. As they speak, Ritsuka thinks to themselves that even if it's pointless or if it feels like it's their imagination, they'll remember Faker all the same for her sake.
== Participants==
Servants
Non-Servants
Designation 	Identity 	Affiliation 	Role
Mystic Code 	Trimmau 	Sima Yi 	
Mystic Code 	Add 	Gray 	
Magus (Fabrication) 	Lev Lainur Flauros 	N/A 	
Demon God (Fabrication)	 	N/A 	
N/A 	Mnemosyne 	N/A 	
N/A 	Rail Zeppelin Deputy Manager	Rail Zeppelin	
N/A 	Rodin 	Rail Zeppelin	
==References==
Category:Locations in Fate/Grand Order
Category:Singularity
Category:Human Order Revision
Category:London
Category:Cities in England