There is not much known about this version of Kariya and it is unknown if he was killed before, during or after the Fourth Ainsworth Holy Grail War. After being brought back to life, the Ainsworth family gave him the Rider Class Card to stop Shirou Emiya who was defeating all the other Card Users of this War.
He takes the appearance of Rider from the Fate/stay night series and the facial scars from his Fate/Zero counterpart. His Install has him wear a dark shirt and pants, with a stitched together Breaker Gorgon and small plate-covered shoes. He has very long hair similar to Rider but coloured white. When revealed his Mystic Eyes are two separate colours; one is purple and the other is a reddish-pink.
Similar to the Kariya from Fate/Zero, this Kariya was also tasked to obtain the Holy Grail when he was alive. This caused him to be obsessed over the Holy Grail even after he died, muttering to himself that he must win at all cost and bring it back.
Fate/kaleid liner PRISMA☆ILLYAEdit
In Fate/kaleid liner PRISMA☆ILLYA Oath of Snow, Kariya battled Shirou, who was determined to win the Holy Grail and save Miyu. Kariya, who was also determined to win, removed his Breaker Gorgon and petrified Shirou, causing too much strain on his body to the point he was coughing up blood. Before Kariya can kill him, Shirou's Kanshou and Bakuya that he had thrown before returns and stab Kariya in the back and releases Shirou, who then finishes him off. Kariya asks which Heroic Spirit Shirou was supposed to be before he dies, something to which Shirou replied "EMIYA".
The ability of Kariya as a magus in this alternate universe is currently unknown though he appears to be physically strained and in pain using the abilities of his Class Card, becoming tired, coughing up blood or creating wounds on his body. After being brought back to life, in terms of strategy, he is obsessed with the fact that he has to win the Holy Grail War in order to rescue Sakura, showing himself to be careless around Shirou and believing quickly in his victory. This causes him to not being able to notice that while he was removing his Breaker Gorgon in order to paralyse his opponent, Shirou had already thrown a pair of Kanshou and Bakuya behind him.
Rider Class CardEdit
As a Card User of the Fifth Ainsworth Holy Grail War, he is able to Install the Rider Class Card. He used Rider's Nail Chains and had Mystic Eyes of Petrification which he blocked with Breaker Gorgon. He attempted to summoned Bellerophon by creating the sigil with the blood he lost overexerting himself using his Mystic Eyes, but was stabbed before he could complete the summoning.