Fate/Zero

Ten years before the events of Fate/stay night, seven mages summon legendary Heroic Spirits as Servants and set them fighting to the death for the Holy Grail. Among them is Kiritsugu Emiya, a magus who works as a freelance assassin and enters the fourth Holy Grail War determined to make it the last one ever fought. Drawn by Shinjirou from Gen Urobuchi's novels, the manga follows Kiritsugu through that war alongside Kirei Kotomine, the conflicted priest whose path keeps crossing his.