Fate/Extra

Fate/Extra - The main character wakes up in a mysterious virtual world, having no memories of his past. Drawn into an inexplicable war, he must fight for a chance to fulfill his most cherished wish. His only ally is a mysterious "Servant" with incredible power. To survive, he will have to battle friends and foes alike, striving to obtain the legendary "Holy Grail" and uncover the mystery of his own identity.