Kiritsugu Emiya

Kiritsugu Emiya is the main protagonist of the light novel/anime series Fate/Zero(although as the story is told from seven different perspectives, this status is fairly debatable) and the Master of Saber during the Fourth Holy Grail War. Being an Anti-Hero, he has several traits commonly found in villains, such as ruthlessness and a belief that there is no rules in battle beyond doing whatever is necessary to win. However, he is very tragic and not particularly proud of his methods, merely seeing them as a means to an end.