Archer of "Black" is the Archer-class Servant of Fiore Forvedge Yggdmillennia of the Black Faction in the Great Holy Grail War of Fate/Apocrypha.

Spoiler

Archer's True Name is Chiron (ケイローン, Keirōn), a centaur, half man and half horse, who was known as a great sage among his kind in Greek mythology. He is the son of the Titan Cronus, patron of the harvest and the earth, and the deity Philyra, making him a Divine Spirit that would not normally qualify for the status of Heroic Spirit. Philyra, ashamed of her offspring's half man and half horse appearance, asked to be transformed into a linden tree by the gods.