A Kaleidostick, a magical device that enables her user to become a magical girl. Though Ruby initially belongs to Rin, Rin's constant squabbling with Luvia causes Ruby to abandon Rin and contract herself to Illya instead. Ruby is Sapphire's older sister.
Ruby is a Mystic Code that resembles a toy Magical Girl Stick. Her appearance consists of a yellow star in a ring that has two small red bead with six white wings (the size of each wing is smaller than the one above it), and a red retractable handle that has a white top with a gold color cross at the bottom.
When not being wielded as a Kaleidostick, she lacks the handle.
Ruby is a cheerful, mischievous, but also sadistic Mystic Code that hates her creator, while also enjoy teasing and annoying her user/master. Aside from her sadistic traits, Ruby can be exceptionally loyal to her master; especially Illya, such as warning her about the dangers of invoking Zwei form on her body. Of course even with her loyalty, Ruby can be extremely manipulative, as she was able to smoothly trick Illya into proceeding through all three steps to establish a contract with it. She holds pride on the standards of a Magical Girl, something that she often berates Illya on.
Comically, Ruby's preferred method of teasing Illya is to reference her crush on her brother and then providing Illya a method to "win" his love, usually through manipulation. She also has used this level of teasing in Illya's relationship with Chloe and Miyu, pointing out the level of intimacy all three of them share.
Fate/kaleid liner PRISMA☆ILLYA
Ruby and her sister Sapphire abandon both Rin and Luvia respectively when they had grown tired of the two's quarreling for the last time. Reverting the transformation on the two girls while they were fighting, the wands left the two to fall from mid-air and went off to find new masters with Ruby's choice being the reluctant Illya.
Ruby plays a minor role in the game. She's been stashed by Rin along with the blueprints for the Jeweled Sword Zelretch in Zelretch's Treasure Chest. When Rin is accidentally trapped inside the Chest along with Shirou, Ruby offers her help to leave, though Rin rebuffs her, remembering the last time she tried to use the wand. On that occasion, Ruby took control of Rin for several hours, after which Rin's friends alienated her as a weirdo.
After a few hours of being trapped in the Chest, Ruby manages to provoke Rin into using her again, transforming her into Kaleido Ruby. Unfortunately, just as everyone leaves the Chest, they're found by Issei and Ayako, leaving Rin to explain why she was inside a chest with Shirou while dressed as a magical girl.
Event: Prisma Causeway
Ruby and Magical Sapphire were with their respective masters, Illyasviel von Einzbern and Miyu Edelfelt, traveling back to the Mirror World when the First Lady summoned them into her Reality Marble. They were attacked by Connacht ☆ Medb, allowing the First Lady disguised as one of Medb's familiar to capture Miyu. Not knowing the truth, Illya blamed Medb and demanded she gives Miyu back. She tried fight but Ruby fled.
She bumps into Mash and detects powerful magical energy from her. She tries to ask for help when Medb attacks with a barrage of spells. Medb demands Ritsuka and Mash hand over Ruby as she summons. Ruby refuses to let her be her master, prompting Ritsuka and Mash to fight the monsters. After slaying the monsters, Mash tries to stop Medb from summoning more, but her attacks prove too weak for some reason. Ritsuka tells her to retreat, but she refuses to give up. Illya then arrives; Ruby promptly joins her side. Illya rejects Medb's attempt to recruit her and demands she give Miyu back. She then has Ruby transform her into her Magical Girl form, and she easily overwhelms Medb. Her next attack meant to finish Medb off is blocked, though, by Medb's familiar, Mini Cu. After Medb and Mini Cu leave, Illya suddenly returns to normal because of the magical energy feed from Ruby not stabilizing for some reason. After Illya explains her circumstances, Ruby confesses to Mash that she analyzed her when she dumped into her. She assumes Mash's Servant designation as a Shielder is her having a very rare class of Heroic Spirit installed. When Ritsuka compares Mash to a Magical Girl, Ruby agrees and notes that Mash has great Magical Girl potential. She, therefore, tries to claim she was seeking help from an unknown Magical Girl when she fled from Medb earlier. Ritsuka and Mash are then contacted by Romani Archaman. He reveals they’re inside a Reality Marble.
Ritsuka returns to Chaldea temporarily, and while they're gone, Mash and Illya encounter the people of the Land of the Sweets. Mash tries to ask them for information, only for the candylanders to abduct her and Illya to their kingdom. Ruby flees back to the Neutral Zone and tells Ritsuka what transpired. The two reunite with Mash and Illya, ad together they fight the candylanders. . Most however flee upon learning that Illya is a Magical Girl. Illya uses this to her advantage to get information. Learning the queen may know more, the group head for Candy Castle.
While heading towards the castle, the group are confronted by what appears to be Tamamo Cat. However, after defeating her, they discover her to be a Mystic Code copying Cat’s form before breaking under the strain.
Arriving in Candy Castle, the group is greeted by the queen, Nursery ☆ Rhyme. She promises to tell what she knows in exchange for playing with her. llya replies they can play later, but Nursery ☆ Rhyme refuses as her only playmate is a black sheep. It turns out to be the Demon God Glasya Labolas. Nursery ☆ Rhyme then proceeds to "play" with the group. Afterward, Nursery ☆ Rhyme gives Illya her jewel, believing it may help find Miyu.
Outside the castle, Mash realizes her attacks were more effective on Nursery ☆ Rhyme compared to Medb. Ruby attributes it to her Magical Girl power increasing. The jewel then suddenly glows and points towards the Land of Dragons and Sea.
As the group sails through the ocean, Romani asks Ruby for her thoughts on Illya and Miyu's ability to return to their world. Ruby answers that neither Illya nor Miyu can use such advanced spells. Even if they could, they wouldn't have the skill and knowledge to precisely select a location to return to. Dragon Tooth Warriors then board the ship. After destroying them, they meet Medical ☆ Medea. Illya and Ruby recognize her from their memories of fighting a Medea in their world. Medea demands to know which kingdom’s Magical Girl they killed to get her jewel. Illya explains Nursery ☆ Rhyme gave it without bloodshed. Realizing they’ve come to take her jewel, Medea invites the group to her castle.
In her throne room, Medea offers to never interfere with the group's affairs if they never interfere with her kingdom. But she'll never hand over her jewel, as it supports her kingdom and grants her power. She then reveals the kingdoms were founded as a result of a conflict between the Magical Girls. Equating the loss of her jewel to her own death, Medea demands the group leave her kingdom. She tells Illya to use her jewel to create a kingdom filled with friends. Illya refuses to do so as she only wants to return home with Miyu. However, Medea reveals Magical Girls cannot leave the Reality Marble and tells Illya she'll use the jewel's power in the end. She continues that Illya should give up on Miyu, revealing Nursery ☆ Rhyme disappeared after giving her jewel as they're what keep Magical Girls alive. Illya refuses to give up though, which makes Medea finally snap and fight the group.
Refusing to be defeated, Medea prepares to transform into her adult self. Illya stops her, however, saying she'll find a way to save Miyu without Medea's jewel. Mini Jason gives her Medea's jewel, not wanting Medea to become a witch. Medea accepts the outcome but remains silent on the subjects of Magical Girls fighting as it'll only bring back sad memories.
Following the light of the jewels, the group arrives in the Land of Dead Bookshelves. Mash notices a large black wall that Romani cannot scan past. A ghost then appears, but the group ignores it since it is passive. After the ghost departs for the black wall, the group continues onto the land’s center. But the jewels' light stops leading them, so Illya transforms to get an overview of the area. However, she and the others are attacked by ghosts that eventually prove too strong and numerous for them. Mahatma ♀ Helena arrives and reveals the land is the graveyard of Magical Girls, and the ghosts are theirs. Recognizing Romani’s communications as a leyline directly linked to a parallel world, Helena realizes “she” found a way to the outside world. She then brings the group into her library so she may continue talking without danger.
Inside Helena's library, Ruby shakes as she likely senses all the grimoires were once Magical Girls. Helena reveals the Reality Marble was created by the First Lady residing beyond the black wall. She then tries to give her jewel to the group, unconcerned that the Echoes will attack her without it. She also informs Ilya of the truth of Miyu's kidnapping. Illya refuses to take the jewel, but Helena reveals the jewels are needed to bypass the black wall as they’re the crystallized emotions that grant wishes. She warns though the First Lady is likely gathering the jewels to use them to escape to the outside world. But she advises against fighting her as the First Lady’s power in the Reality Marble is absolute. She then demands Illya take her jewel, forcing Illya to fight her. After she's defeated, Helena accepts Ritsuka's offer to join their group.
Returning to the Neutral Zone, Helena reveals Medb is forming a rebellion against the First Lady, which explains Medb trying to recruit Illya earlier. After slaying Medb’s monsters, Ritsuka and Mash lose contact with Romani. He reestablishes contact but reveals Chaldea's Servants just repelled an assault on the facility using its leyline connection. He gives Ritsuka and Mash five minutes to decide whether to return to Chaldea or stay with Illya. Suddenly it starts to snow, signifying that Medb is attacking the surrounding lands. Ruby has Mash return to normal as her power is solely dependent on Ritsuka’s magical energy with the connection with Chaldea now cut. After the group decides to stay and help Illya, Ruby has Illya teach Mash how to recharge her magical energy through kissing. Romani then reestablishes contact to hear Ritsuka and Mash’s decision.
After Ritsuka and Mash tell Romani of their decision, the group travels to the Land of Sweets, which has been assimilated into the Land of Snow and Honey. There they fight Mini Cu's monsters despite Mash being weakened in Medb’s territory. After his monsters are slain, Mini Cu prepares to unleash his Noble Phantasm, Gentle Bite Coinchenn, on Illya, even though he knows Medb wants to recruit her. Mash protects Illya when Magical Sapphire suddenly appears. Sapphire agrees with Ruby’s request to temporarily contract with Mash since she is Illya’s ally. After Sapphire contracts with Mash, Mini Cu retreats as Helena tells him to tell Medb that Illya has two jewels. Sapphire then plays a message from Miyu. Miyu reveals she is imprisoned in the First Lady's castle, and the latter has been luring Magical Girls from different worlds into the Reality Marble. She suspects it's for a nefarious purpose, and it's related to her captivity. She then ends the message warning Illya not to come. Ruby suspects the First Lady has power over Magical Girls, given that Miyu is still transformed despite Sapphire's distance from her. Sapphire believes Miyu doesn’t want Illya to come because she knows something about the First Lady’s true identity. Helena only heard that the First Lady was the first Magical Girl.
After Helena gives her jewel to Illya, the group enters Medb's castle without Helena. Inside the throne room, the group fight Medb. They defeat her and Illya unintentionally breaks her by saying the former considered the Magical Girls who disappeared as her comrades. As proof, Medb's castle begins to collapse. Ritsuka and Illya plead with Medb to come with them. But Mini Cu tells them that's impossible as Medb can no longer bear the strain of forcibly interfering with parallel worlds. The group then escapes the collapsing castle, leaving Medb and Mini Cu to disappear together. Medb’s jewel appears in Mash’s hand. Illya returns Helena’s jewel to her. With all four jewels, the group can now bypass the black wall.
Returning to the Neutral Zone, the group watches the black wall disappear. Illya, Ruby, and Sapphire fly up to get an overview of the First Lady’s kingdom. The First Lady's familiars soon approach. Illya, Ruby, and Sapphire rejoin the others and warn them of the approaching familiars. They eventually breakthrough and enter the First Lady's kingdom.
As they head closer to the First Lady's castle, the group is attacked by a large enemy force. Using power borrowed from Ruby and Sapphire, Illya initially tries to hold off the enemy herself so the others can go on ahead. She eventually exhausts herself, though, fighting so many enemies. Helena takes over from her so Illya can meet the First Lady with Ritsuka and Mash.
Inside the First Lady’s throne room, the group sees Chloe von Einzbern on the throne. Chloe reveals that she and Miyu have been in the Reality Marble for a very long time, though she’s been in it since the beginning. The group finds Miyu restrained by the Anti-Magical Girl Mystic Code, Voile de Deuil, part of which turns into hostile familiar when Mash tries to check Miyu’s condition. Chloe reveals that she secretly followed Illya and Miyu into the Mirror. She ended jumping into the Reality Marble but became trapped, arriving during the Magical Girls conflicts. She hid her presence, but her magical energy soon depleted. That was when she met the First Lady through her familiar. She calls her appearance in the Reality Marble an inevitability as the First Lady turned her against Illya by calling her an accessory to Illya. Illya denies that, but Chloe projects a weapon in response and fights her.
Their shared pain puts Chloe at a disadvantage when she reveals she is the First Lady’s vessel. The First Lady then possesses her. She explains her history and how her desire to spread the Magical Girls’ magic of love and hope throughout the world attracted Echoes to the Reality Marble. She attempted to use them to grant her wish by giving them temporary bodies and bodies, but it failed because they weren't real Magical Girls. That is when she met Chloe and made her into her vessel. With Miyu’s power, the First Lady will incarnate the Echoes into Magical Girls and spread them across parallel worlds to save people. She’ll soon absorb Miyu, as Chloe resists assimilation with her. Miyu asks Illya to help Chloe and the First Lady both, saying the latter has an impossible wish in her heart. Chloe briefly takes back control of her body before the First Lady retakes control. The First Lady reveals her and Chloe’s desire for Miyu allowed her to break through the latter’s mental wall and fully control her body. Once Miyu is emotionally broken by seeing the group dead before her, she’ll use Miyu to reach infinite parallel worlds. The group then fights the First Lady to save her from herself.
With the First Lady defeated, Chloe slowly regains control of her body, and Miyu is freed. The First Lady confuses she killed her best friend to protect the world when she refused to be a Magical Girl. Helena then arrives and takes everyone outside.
There they encounter the passive Echo from before. Ruby has it possess Illya; the First Lady recognizes her as her friend Mila. Mila became an Echo since she was a Magical Girl, even if it was for a brief time. After Mila explains her circumstances, Ruby realizes she is the corrupted Magical Girl. Helena convinces the First Lady to give her ownership of the Reality Marble so it can serve as a refuge for wounded Magical Girls to stop them from becoming like the First Lady. The First Lady and Mila then reconcile and disappear. Afterward, everyone uses the power of the jewels to return their respective worlds.
As a Kaleidostick Mystic Code, Ruby can access the Mana Plane and provide her user/master unlimited magical energy. She can decide who can be her user/master through a three-step contract, while also allowing a temporary contract for others who wish to wield her.
Ruby's combat functions allows her to manipulate the Od within the user and assist them by either acting as medium to fire energy blasts or reinforce physical parameters. More experience users like Rin display the ability to condense mana onto the tip of the wand to create a blade durable enough to clash with Excalibur.
Ruby also has the ability to Include and Install Class Cards. This makes Ruby transform into the respective weapon of the Class Card's Heroic Spirit. When Illya Installed the Berserker Class Card and overwrite it with Rider which inherited the Berserker Class, Ruby is able to bite her opponents with a poison.
Defensively, Ruby can form a transparent barrier with A-rank strength that while powerful by modern standards, can only barely resists attacks like Caster's Rain of Light spell from the Age of Gods as Illya could still feel the intense heat from the beams. In close combat situations, the shield can be compress into a sort of second skin strong enough to stop a slash from Excalibur, but doing so would require diverting a large portion of mana. With the proper training and/or the right amount of imagination, the Kaleidosticks can also grant their users the ability to fly.
Outside of combat, the Kaleidosticks have demonstrated the ability to transform into wireless communication devices complete with live video chat. The two wands can also trade data between each other with a built in USB-like wire and port. She can record and project videos like a camera. When she isn't being wielded, she is able to move on her own by flight.
Another among of Ruby's device functions is called Secret Device #18 which allows Ruby to predict an immediate future event based on statistics and event fluctuation patterns based on the target's life.
Humorously, it has been implied that Ruby is a very skilled chemist as she keeps multiple powerful sedatives, able to cause the victims to enter a 'nirvana'-type trance when injected, handy as well as a truth and love serum.
- Fate/Grand Order - Prisma Causeway, Prolog: Grave of the Abandoned
- Fate/Grand Order - Prisma Causeway, 4ier!!!: The Land of Snow and Honey III
- Fate/Grand Order - Prisma Causeway, 4ier!!!: The Land of Snow and Honey IV
- Fate/Grand Order - Prisma Causeway, 1ins: A Strange, Strange Land of Sweets II
- Fate/Grand Order - Prisma Causeway, Land of Sweets EXTRA I
- Fate/Grand Order - Prisma Causeway, 1ins: A Strange, Strange Land of Sweets III
- Fate/Grand Order - Prisma Causeway, World End Match: Nursery★Rhyme
- Fate/Grand Order - Prisma Causeway, 2wei!: the Land of Dragons and Sea I
- Fate/Grand Order - Prisma Causeway, 2wei!: the Land of Dragons and Sea II
- Fate/Grand Order - Prisma Causeway, 2wei!: the Land of Dragons and Sea III
- Fate/Grand Order - Prisma Causeway, World End Match: Medical★Medea
- Fate/Grand Order - Prisma Causeway, 3rei!: the Land of Dead Bookshelves II
- Fate/Grand Order - Prisma Causeway, 3rei!: the Land of Dead Bookshelves III
- Fate/Grand Order - Prisma Causeway, World End Match: Mahatma Helena
- Fate/Grand Order - Prisma Causeway, 4ier!!!: The Land of Snow and Honey II
- Fate/Grand Order - Prisma Causeway, World End Match: Connacht★Medb
- Fate/Grand Order - Prisma Causeway,Ietztes: The Land of Stars and Crystals I
- Fate/Grand Order - Prisma Causeway,Ietztes: The Land of Stars and Crystals II
- Fate/Grand Order - Prisma Causeway,Ietztes: The Land of Stars and Crystals III
- Fate/Grand Order - Prisma Causeway,Ietztes: The Land of Stars and Crystals IV
- Fate/Grand Order - Prisma Causeway, World End Match: First Lady
- Fate/Grand Order - Prisma Causeway, Epilog: The Windflower Blooming in the Breeze
- Fate/kaleid liner PRISMA☆ILLYA 2wei! - Chapter 2