Illyasviel von Einzbern

 Illyasviel von Einzbern (イリヤスフィール・フォン・アインツベルン, Iriyasufīru fon Aintsuberun?), often referred to as Illya, is the Master of Berserker in the Fifth Holy Grail War of Fate/stay night. She is the daughter of Kiritsugu Emiya and Irisviel von Einzbern, both who participated in the Fourth Holy Grail War, and the adoptive older sister of Shirou Emiya.