|Appears in:||Fate/Somnium Summer|
|Voice actor:||Konishi Katsuyuki|
|Hair color:||Blonde, in a ponytail|
|Eye of the Mind (True)||B|
|Eternal Arms Mastership||A|
Rider is the Servant of Takako Karin in Fate/Somnium Summer, and the protagonist of the story. He is a strong Servant with a obsession on fighting all his enemies while they are at their strongest, and bringing them down. He also, at first, has no weapon that would hint to his identity, and later he is seen using multiple Noble Phantasms, none of which are representative of his true identity.
Noble Phantasm Role Rider has played a major role in Fate/Somnium Summer, being it's protagonist and the narrator. Rider was summoned accidentally by Takako Karin when Servant Assassin attacked her. After that, he has continued to protect his Master, whom he feels a bond with, as both are persons with very fragile sense of self. Rider has also "acquired" other Master, Tuuliveta Edelfelt, who bound herself to him with a powerful conceptual artifact known as "Scarf of Aino". Right now, he is getting extra prana from Tuuliveta, though most of it still goes to Tuuliveta's own Servant, Berserker.