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 Phantasmal Collection Domain: Patchwork London (幻想蒐集領域パッチワーク・ロンドン^?) 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; Lady Reines Case Files (レディ･ライネスの事件簿^?), referring to a collaboration between Fate/Grand Order and Lord El-Melloi II Case Files.

Setting

Map of the Singularity's London.

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 traveling through the underworld. 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

Ritsuka is woken up on a train by a mysterious girl, who addresses them as her disciple. She introduces herself as Lord El-Melloi II. Ritsuka sees vague memories of Sherlock Holmes, Goredolf Musik, and Mash Kyrielight discussing their latest Rayshift, but they can’t remember who they are. They exit the train to London with El-Melloi II carrying her luggage. El-Melloi II suggests first returning to her flat when Ritsuka notices a darkened Clock Tower. Eventually, the pair arrives outside of her flat when she notices something is amiss with its Bounded Field. She then forces an automaton that ambushed them to retreat. Feeling like they’re being watched, she and Ritsuka enter her flat.

El-Melloi II found dead in his flat.

The pair find the corpse of the real El-Melloi II in the study. “El-Melloi II“ becomes confused as to why she thought she was El-Melloi II. She then notices an “M“ written in blood near El-Melloi II when an automaton suddenly bursts in. After defeating it, reinforcements arrive, so “El-Melloi II“ orders an immediate retreat through the window. Despite them being on the fourth floor, she pushes Ritsuka out of the window and follows them after activating Trimmau.

Patchwork Fairy Tale

Upon landing outside, “El-Melloi II“ shoots a magical bullet to destroy the automatons inside before retreating with Ritsuka and Trimmau. She then introduces 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 surmises she and Ritsuka both had their memories falsified. She then realizes something is wrong with this world, which triggers the town to warp. As it does, a garbled transmission from Mash says something about Saint Graph Trunk. After the transmission cuts, the town is 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 trunk she thought was hers is the Saint Graph Trunk. She then decides they need to find whoever killed El-Melloi II and stole their memories. Though stumped on how to proceed, she knows the “M“ is their leading clue. She wonders about the bizarre scenery when Paul Bunyan reveals the town is called Patchwork London, a patchwork of fairy tales. She then carries Reines and Ritsuka on her shoulders after saying she knows about the “M“.

Patchwork Fairy Tale museum

Bunyan takes the pair to a museum, where she is welcomed back by Sakata Kintoki and Jack the Ripper. Ritsuka suddenly recalls meeting them before. Bunyan asks Ritsuka and Reines to help find her friend, but neither she nor Kintoki remember who it is. She explains that since the museum is filled with enemies Jack and Kintoki defeat, and she cannot enter herself, she sought help when she found Ritsuka and Reines. Reines agrees to help and asks Bunyan about the enemy’s identities. As Bunyan describes them, the very same monsters emerge from the museum. In response, Ritsuka uses the trunk to summon Servants to fight the monsters. Afterwards, they, Reines, Jack, and Kintoki enter the museum.

The group makes a full circuit of the museum and leaves after dealing with a monster ambush. Reines asks Jack when her friend went missing. But neither Jack nor Kintoki can remember, so Reines suggests allowing her and Ritsuka to explore the museum on their own, which Kintoki allows.

Patchwork Fairy Tale museum library

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. There, the pair find a talking book hidden amongst the others. Reines deduces it is Bunyan, Kintoki, and Jack’s missing friend, and their true form is a book. Ritsuka then recalls meeting them before. After the book takes the form of a young girl, Reines deduces the girl forgot about her friends as both she and her friends forgot who or what she was. The girl introduces herself as Nursery Rhyme. Reines tells her that her friends are waiting at the museum’s entrance. After Nursery Rhyme leaves, Reines notices a scrap of paper where Nursery Rhyme in her book form was. The paper reads Mnemosyne, which makes Reines wonder if it is what the “M“ referred 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. Mash then contacts them, and they tell her about El-Melloi II’s murder and their amnesia. Mash reveals Ritsuka had Rayshifted into a Singularity that appeared at the end of 19th century London, while El-Melloi II was the Servant selected to accompany them. During the Rayshift, however, communications were completely severed, and Ritsuka and El-Melloi II’s signal was lost. Chaldea needed to reset communications and other systems just to barely allow Mash to contact Ritsuka. Mash then reveals there was a recent change in the Singularity's topography and tells Ritsuka and Reines to investigate.

Arriving in a new territory of Patchwork London, Ritsuka and Reines notice everyone is wearing masks, so Reines dubs it Patchwork Masquerade. She deduces each Patchwork is centered around a theme, with the first being fairy tales. Mash asks the pair if they’ve noticed anything strange in their memories. Reines replies it would be difficult to tell currently, but they’ll be cautious nonetheless. Mash agrees to tell them immediately if she notices anything when she detects a large source of magical energy nearby. Reines deduces it’s from the palace, the Tower of London, and heads there with Ritsuka after Mash cuts the transmission.

Patchwork Masquerade

Upon entering the palace, Reines deduces it is a patchwork of its history. The Masquerade soon begins; Reines questions why the pianist is absent despite the piano being the central performance. The music causes Ritsuka to remember Antonio Salieri, making them wonder if he’s the pianist. The piano then stops in the middle of the song, and upon hearing it has happened before, Ritsuka and Reines decide to investigate further. An old man then suddenly hands them masks that they proceed to wear. He introduces himself as M since the Masquerade is where names aren’t given. Ritsuka reacts under the assumption of M refers to El-Melloi II’s dying message. Reines quietly warns them not to react so openly and says they need to think on how to proceed if M is the murderer or an accomplice. Asked by Reines, M explains the pianist’s identity is unknown since every investigation involving them is unauthorized. The only fact known about them is that they reside in the palace. He then decides to take the pair to the Bloody Tower where the pianist supposedly resides.

Outside the palace, M warns the pair that the Bloody Tower’s security is strict on this path. He tells them to scale up the wall while he distracts the guard. He starts distracting the guards when mask wearing ghosts suddenly appear. After destroying some ghosts, the group enters the tower.

Piano room inside the Bloody Tower

Inside the tower, while M goes on ahead, Reines asks herself a particular question. She explains to a confused Ritsuka that was Sima Yi, the Heroic Spirit possessing her. His question was why he was summoned, which she also wants to know. 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 the automatons already kidnapped the pianist. Ritsuka recalls meeting Shakespeare in the London Singularity. Shakespeare explains he wanted to see the pianist himself and reveals M lied about names being banned in the Masquarede. The Queen then enters the room with her guards and assumes the group kidnapped the pianists, even though M introduced her to them. M responds he and the others came to find the pianist as well. Reines asserts they are innocent and tells the Queen she and Ritsuka will solve this mystery. The Queen agrees to reward them if they do. After the Queen and her guards leave with Moriarty and Shakespeare in their custody, Reines deduces they're all connected to the pianist. She then suddenly fires a blast at EMIYA hiding behind the piano, having sensed him earlier while conversing with the Queen but didn’t reveal him so to avoid complications. He claims he isn’t the kidnapper and flees out the window with the others giving chase.

Landing outside the tower, Reines orders Trimmau to not let Assassin escape. While the three are fighting, Assassin tries to shoot Reines, but Trimmau protects her at the cost of damaging herself. In response, Reines activates Sima Yi’s Noble Phantasm, Unspeakable Formation, to restrict Assassin’s movement. He struggles against her and Ritsuka when his client arrives, who calls him Kerry. Reines recognizes her as Luviagelita Edelfelt and a Pseudo-Servant. Luvia warns Ritsuka and Reines to stop investigating Mnemosyne for their own good. Trimmau isn’t able to read her magical energy. Reines realizes Luvia is fused with a Divine Spirit and decides it's best not to fight her. After Luvia and Kerry leave, Ritsuka and Reines go question the suspects of the missing pianist case. After questioning them, she orders Trimmau to sift through her unconsciousness for any keywords. Trimmau reports she has discovered three keywords: forgetfulness, ghost, and Pseudo-Servant. Reines ponders about the connection when she realizes something about the pianist. The pair then return to the piano room.

Upon returning to the piano room, Reines finds a Mnemosyne scrap in the automaton like she deduced there would be. She deduces the scrap was used to instill the automaton with specific human memories and allow it to move. Everyone knew, but they forgot. Everyone knew, but they forgot. She then invites the eavesdropping M into the conversation. M remembers Salieri wasn’t able to be summoned in the Singularity because his Saint Graph was insufficient. Thus, he and Shakespeare decided to create a substitute. He created the plan, while Shakespeare did the composition. By coincidence, they found the Mnemosyne scrap and used it for magical energy. They then presented the fabricated Salieri to the Queen, who accepted the arrangement. But when they forgot that the pianist was a facade, the automaton went berserk. Reines prepares to retrieve the scrap when Luvia arrives to punish them. Ritsuka and Reines fight her, while M holds Kerry off. The pair struggle against Luvia when automatons arrive to capture Reines, who they assume to be El-Mello II. They’re quickly destroyed though by Gray, and Ritsuka retrieves the scrap.

After re-experiencing their battle against Goddess Rhongomyniad, 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 Patchwork of Dazzling Steam. She then introduces Gray as El-Melloi II’s disciple. Because of her status as a Servant, Gray understands the current situation , though, like Reines, she isn’t unsure why she was summoned. After Ritsuka temporarily contracts with Gray, Reines reveals the Divine Spirit possessing Luvia is Astraea. Mash reveals through her analysis of the previously collected Mnemosyne scraps that there are smaller scraps. The group set out to find and retrieve the scraps.

Patchwork of Dazzling Steam

Outside of the hotel, the group sees a parade of automatons riding steam-powered horses, with the Patchwork's king, Charles Babbage, riding in a steam-powered wagon. Suspecting Babbage has a connection with the scrap, Reines goes alone to search for a clue to prove that connection. She eventually returns with the Queen, who was looking for them to grant their promised reward. The group request a meeting with Babbage as their reward. The Queen agrees since she was planning to meet with him anyway.

Charles Babbage's throne room

The Queen takes the group to Babbage’s throne room. After learning of their search for the Mnemosyne scraps, Babbage asks them to destroy his kingdom, as it is an unnatural realization of his dream. He reached this conclusion thanks to the Astraea’s guidance, who appears in the room. She reveals everyone in the Singularity, including herself, are missing memories. She found it was necessary to compensate it with the scraps, so she went searching for them in the Patchwork Masquerade after meeting with Babbage. Babbage reveals the scrap is infused into his body when Reines asks where it is. He explains the scraps are central to each Patchwork, and they immediately seek residence in what’s closest. Since the scrap is likely infused with his Spirit Core, he requests the group to kill him, calling it a last resort when they refuse. He reveals Astraea searched for an alternative in the other Patchworks, which explains why Ritsuka and Reines met her in the Tower of London. He then tells the group to locate his subsystem located somewhere in his castle.

Difference Engine absorbing ghosts

As the group search for the subsystem, Gray finds a particular spot on a wall. Ritsuka opens it to reveal a secret passage. It continues on underground, and eventually the group encounter steam ghosts that Reines calls unnatural. After the ghosts are destroyed, Gray explains they weren’t acting on their memories in life like actual ghosts. The group soon reaches the core of the castle, a massive steam engine, and witness ghosts being absorbed into it, whose magical energy they deduce powers the engine. Trimmau reports the engine has traces of a Mnemosyne scrap that someone retrieved prior. Reines surmises the steam ghosts are the result of the scraps’ magical energy and ghosts fusing with the steam. After destroying the steam ghosts, the group finds Babbage’s subsystem, the Difference Engine. Reines uses it to discover that it was El-Melloi II who retrieved the scrap. She also realizes Babbagge forgot the scrap was in the engine. She further realizes the enemy’s goal wasn’t to consume their memories, but to use the energy from them, though the energy retrieved isn't great. Gray realizes the ghosts in the castle and the Tower of London had high levels of magical energy and the scraps had even more. Reines deduces there is something about the Singularity that makes memories an extremely potent energy source. She further deduces the Difference Engine has been working independently and surmises the automatons went after her brother to get back the scrap he stole. She then says they need to return to her brother’s flat immediately.

• Patchwork Fairy Tale warped into a burning city
• Rhongomyniad clashing with Custos Morum

1/2

The group returns to Patchwork Fairy Tales to discover it has been warped into a city consumed by fire. Automatons and steam ghosts piling on each other in what remains of El-Melloi II's flat, each trying to get the scrap. Astraea soon arrives and uses her Noble Phantasm, Custos Morum, to destroy automatons and steam ghosts, then goes to retrieve the final scrap. The group gives chase to reach the scrap before she does while fighting through enemies, and avoiding the remaining stars from her Noble Phantasm. However, far too many enemies stand in their way, as Astraea nearly reaches to the scrap. Gray prepares to unleash her Noble Phantasm to stop her when Kerry arrives and stops Gray. 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 is easily breaks through. With Astraea down, the group rush to reach the scrap. However, upon touching the scrap, Ritsuka finds their memories of Da Vinci are being erased. A figure tells them to accept those as no longer being the truth when El-Melloi II breaks the process. He reveals the scrap was a trap. Reines and Mash doubt it’s really him, to which he explains he as a Pseudo-Servant, has two Saint Graphs: his and Zhuge Liang. Thus, he created a corpse of himself through the separation of Zhuge Liang’s Saint Graph. While it left him without nearly all of Zhuge Liang’s powers, it also allowed him to investigate without being detected as a Servant. He reveals the scraps were being used to manipulate Ritsuka’s memories, suspecting their memories were stolen from the moment they arrived. But to rewrite Ritsuka’s memories, the enemy arranged for the scraps to be placed at certain locations for Ritsuka to retrieve of their own volition. The first two contained Ritsuka’s original memories, while the third was meant to implant fabricated memories. El-Melloi II concurs with Gray that Chaldea would know whether Ritsuka’s memories are true or not. He questions, though, why they’ve been only received transmissions from Mash, and explains the enemy needed someone Ritsuka absolutely trusted to guide them. Reines then deduces the “M“ in El-Melloi II’s message was for Mash. El-Melloi II reveals the Mash they’ve been talking with so far is a fake. After “Mash“ blocks communications, El-Melloi explains the enemy fabricated her to manipulate the group. He therefore suspects the enemy has information on Chaldea and believes the final scrap is related. He cannot deduce anymore though with his analysis of the final scrap, but he says Babbage could provide a deeper analysis. The group then return to Babbage’s castle with El-Melloi II, Astraea, and Kerry.

Babbage agrees to analyze the scrap, believing it may provide clues to the enemy. The analysis will take time, so he invites the group to rest in his castle. He believes the enemy would know why Ritsuka needed false memories implanted into them when Astrae asks why. He also wonders what particular memories of theirs were being erased. El-Melloi II deduces the enemy pities them, with good yet ill intentions. Reines then realizes she, Luvia, and Gray were summoned because El-Melloi II failed, meaning when he created the corpse because he was driven into a corner. She, Gray, and Luvia were more inclined to be summoned because of their deep connections with him. 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 and explains it grants allies the abilities they need, which in this case, was to provide Reines and Luvia with Servant Saint Graphs. Its effects wouldn’t be that tremendous if it weren't for humanity being in dire straits or the Singularity’s circumstances. Reines deduces Sima Yi was summoned thanks to his connection with Zhuge Liang. 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.

Fake Rhongomyniad

Later, El-Melloi II reveals the Singularity was ready to collapse when Ritsuka woke up, so it consumed their memories to lengthen its lifespan. The group then rushes to the castle’s balcony when Reines retrieves them. Reines realizes their awareness of the Clock Tower was obstructed, so they never saw it was a fake Rhongomyniad.

Babbage reports many steam ghosts and automatons are emerging from its interior, with approximately 80% of them heading out to capture Ritsuka. He then gives his analysis of the final scrap, revealing the enemy is related to Chaldea. El-Melloi II assumes they’re a traitor since they knew both Mash’s appearance and mannerisms. Babbage then gives the second name revealed in his analysis: Mnemosyne, a system of Chaldea. Reines and Astraea decide to assault the fake Rhongomyniad, but Babbage warns against it with all the enemies swarming out. Gray says she could clear a path, but she lacks the magical energy to do so. El-Melloi II suggests collecting the smaller scraps for magical energy and asks Babbage to provide a countermeasure against their fabricated memories.

Joined by Babbage, the group search for the smaller scraps, and fight through their fabricated memories. A memory of fighting Ultra Heroine Z, except a alternate version of Mysterious Heroine XX called Super Heroine ZZ also joins in. A memory of the first battle against Gawain at Holy City Camelot's main gate during the Camelot Singularity, but his Gift of Nightlessness doesn't function. A memory of the battle against Black Iri, though she later transform into a corrupt version of Illyasviel von Einzbern. A fabricated memory of fighting Medea and Heracles during the Okeanos Singularity. A fabricated memory of fighting a horde of corrupt Musashibou Benkeis, who are weakened by Ushiwakamaru's Benkei - Steadfast Position and finished off by Jumping the Eight Ships at Dan-no-ura.

Crystal stairway created by Gray wrapping around the fake Rhongomyniad

With the smaller scraps collected, Gray uses their magical energy to create an opening in the fake Rhongomyniad and a crystal stairway to it. While Ritsuka, Reines, Gray, and Astraea ascend the stairs, Babbage, El-Melloi II, and Kerry prepare for the onslaught of automatons and ghosts. Meanwhile, Bunyan, Jack, and Kintoki, the Queen, and Shakespeare defend their respective Patchworks from the automatons and ghosts. The group continues ascending the stairs when they’re transpoted into a fabrication of the Battle of the Time Temple by a sudden Mnemosyne scrap. There they are confronted by fabrications of Lev Lainur Flauros and Barbatos. Ritsuka recalls fighting Barbatos in the London Singularity, and Reines realizes the enemy is using that link to create the fabrication. While Astraea bombards the Demon Gods with Custos Morum, Reines Unspeakable extracts Ritsuka’s memories of fighting the Demon Gods for her Noble Phantasm. Then, after Barbatos is fought several times, she uses her Noble Phantasm to rewrite the fabrication so Ritsuka is the Demon Gods’ conceptual weakness based on the fact Ritsuka slew more than anyone in history. With the fabricated Barbatos destroyed, the group continued their ascension.

Fake Rhongomyniad interior

Eventually the group enters the fake Rhongomyniad’s interior, but Astraea is suddenly forced outside. Closing the opening, the enemy explains they created the fabricated memory from earlier in order to weaken Astraea since she was a major threat. Taking on the appearance of Da Vinci, the enemy reveals she was originally a formless program; Reines deduces she is Mnemosyne. Mnemosyne reveals she is a subsystem for verifying a Master's existence during rayshift. Prior to rayshifting, staff members would verify reality at the destination to ensure the Master’s safety. Mnemosyne was created as a system to ensure the Master still existed in case the staff died. However, due to technical issues, she was never implemented. Reines realizes Mnemosyne is trying to ensure Ritsuka is protected. Mnemosyne demands the group hand Ritsuka over and fights them. The battle ends when they’re struck by something akin to a Noble Phantasm. Reines deduces Mnemosyne is using the memory of Rhongomyniad since the fake one is her body. She tells Gray to use Rhongomyniad, but Add says he isn’t able to. Mnemosyne reveals she can interfere with Gray’s Rhongomyniad to prevent its activation like Gray can also do. She did so before the group arrived, since it would be their key to a swift victory. She then uses the Grail to transport Ritsuka into a space of memories.

Mnemosyne's oldest memory

Ritsuka is shown Mnemosyne’s oldest memory during her construction. However, since she was never completed, she could only observe the Incineration of Humanity. After humanity was restored, her data was transferred into the Shadow Border, which changed her heavily. When the Chaldean survivors established their base at the Wandering Sea, Mnemosyne reawakened, only to discover A-Team betrayed humanity, and the world turned blank by the Fantasy Trees. Upon discovering her creator, Da Vinci, was dead, Mnenosyne used her functions of observation in the conjunction with her Grail to create the Singularity. She also realized she could use her observations to determine the truth and decided to use that ability to erase Ritsuka’s painful memories after realizing she could use her observations to determine what’s true. She reveals she created the three Mnemosyne scraps to take their memories in order to guide to them, so it would be easier for Ritsuka to accept the newly created memories. But instead of simply giving them to Ritsuka, she wanted Ritsuka to go through proper tribulations and turn them into their utmost version of themselves. El-Melloi II’s intervention ruined that intention, however, for which Mnemosyne apologizes. She tells Ritsuka to receive her memories and proceeds to erase theirs. However, Gray uses Rhongomyniad to create a link into the space. Mnemosyne claims the effort is too late though, as she already has complete control over Ritsuka and their memories. She argues with Reines that Chaldea has been too tragic for Ritsuka, claiming she awakened to save them from their flaws and sorrows. Ritsuka, however, refuses to let her take their memories away. Mnemosyne replies she will need to break them, believing they are 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 exterior of the fake Rhongomyniad. It was M’s Noble Phantasm, with him having sacrificed himself to increase its distance and damage output.

With Ritsuka out of Mnemosyne’s space of memories, Astraea enters the fake Rhongomyniad’s interior. She uses her second Noble Phantasm, Iam Redit et Virgo, to clear the sky of the smog that blocked Chaldea’s communicators. Mash reveals they lost contact with Ritsuka after they rayshifted, but they still had their location. Reines then reveals the motives for each Patchwork. Patchwork Fairy Tale wanted to be searched for; Patchwork Masquerade wanted to talk without their identities being known; Patchwork of Dazzling Steam wished to forget. Reines concludes Mnemosyne created the Singularity centered on memory loss because she was the one who wanted to forget. Trimmau reveals the synergy between Mnemosyne and the fake Rhongomyniad has decreased due to Astraea’s Noble Phantasm, so the group use this opportunity to defeat her. 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 group escape before it finally collapses.

With the fake Rhongomyniad now destroyed, everyone begins to disappear with the Singularity’s imminent collapse. Astraea and Reines both wish the bonds they formed with Ritsuka will let them be summoned to Chaldea before disappearing. Meanwhile, Mnemosyne accepts she will lose the magical energy granted by the Grail and the Singularity will be resolved. Before losing power, she dreams of Da Vinci praising her for her work.

At Chaldea, El-Melloi II apologizes for getting Ritsuka into such a dangerous situation. He then deduces the Da Vinci that appeared before Mnemosyne at the end was Reines using Unspeakable Formation on her. He also accidentally brought Gray back with him. Gray shows she has the Grail Mnemosyne used; Da Vinci deduces that it responded to the real Rhongomyniad and Gray’s wish to stay with El-Melloi II. Goredolf commends her for bringing back the Grail, calling it a physical record of her accomplishment. Ritsuka then 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 decode the Singularity so they could enter it directly; 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.

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 plan. 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 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 their world Marisbury Animusphere won the Mystic Eyes auction. "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 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 starts releasing colossal amounts of magical energy. Mnemosyne had failed to replicate Rhongominyad's seals, and the release of the memories she had contained overcharged it, inverting its normal function from maintaining Textures to distorting them and turning it into a "Nega-Rhongominyad". Furthermore, it had developed a crude self-preservation instinct, and was now breaking down everything in the Singularity to sustain itself. 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

Designation	Identity	Affiliation
Rider	Sima YiWP	Ritsuka Fujimaru
Berserker	Paul BunyanWP	Patchwork Fairy Tales
Berserker	Sakata KintokiWP	Patchwork Fairy Tales
Assassin	Jack the RipperWP	Patchwork Fairy Tales
Caster	Nursery RhymeWP	Patchwork Fairy Tales
Archer	James MoriartyWP	Patchwork Masquerade
Caster	William ShakespeareWP	Patchwork Masquerade
Saber	King ArthurWP (Alter)	Patchwork Masquerade
Assassin	EMIYA	Astraea
Ruler	AstraeaWP	N/A
Assassin	Gray	Ritsuka Fujimaru
Caster	Charles BabbageWP	Patchwork of Dazzling Steam
Caster	Zhuge LiangWP	Ritsuka Fujimaru
Assassin (Fabrication)	Ultra Heroine Z	N/A
Foreigner (Fabrication)	Super Heroine ZZ	N/A
Saber (Fabrication)	GawainWP	N/A
Avenger (Fabrication)	Irisviel von Einzbern (Blackened)	N/A
Avenger (Fabrication)	Illyasviel von Einzbern (Blackened)	N/A
N/A (Fabrication)	JasonWP	N/A
Caster (Fabrication)	MedeaWP	N/A
Berserker (Fabrication)	HeraclesWP	N/A
Archer (Fabrication)	IshtarWP	N/A
N/A (Fabrication)	Musashibō BenkeiWP (Blackened)	N/A
Rider (Fabrication)	UshiwakamaruWP	N/A
Pretender	Hephaestion-Mnemosyne	Ritsuka Fujimaru (Memory)

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)	BarbatosWP	N/A
N/A	Mnemosyne	N/A
N/A	Rail Zeppelin Deputy Manager	Rail Zeppelin
N/A	Rodin	Rail Zeppelin