True Assassin

"It looks like your weapon is a projectile weapon as well. Would you like to try a match?"

- True Assassin, Fate/stay night

The True Assassin is a villain from Fate/stay night. He is an exceptionally dangerous Servant with a limited appearance in both said title and Fate/hollow ataraxia but has an expanded role in Fate/Zero. The designation of "True" is meant to distinguish this Assassin from the one that Caster summoned which not only broke the rules of the fifth Holy Grail War but also saw to it that said Assassin usurped this one's place in the war. All True Assassins share a collective identity and have appeared in every Holy Grail War throughout history. They are all infamous for wearing an ebony and tattered costume, as well as concealing their identity behind an ashen skull mask.

This Assassin, in particular, was summoned by Zouken Matou through the use of the corpse of Caster's Assassin-class servant as a catalyst in the Heaven's Feel route. Zouken did so because he was disgusted by Rider losing to Saber and enraged at his grandson Shinji Matou's incompetence, so he decided to enter the Holy Grail War and summon True Assassin. True Assassin later attacks and devours Lancer to gain the ability to speak normally.

Appearance
His appearance is that of a slender, dark man with his right arm bandaged. According to Saber, his right arm is described as a useless flat board, incapable of doing much. His face, as revealed by Sakura in Heaven's Feel, is that of a skull, without any skin, which inspires her to say that he tries to live for eternity when he has already lost his identity.