Fate/Zero is a Japanese light novel series written by Gen Urobuchi and illustrated by Takashi Takeuchi. It serves as a prequel to all routes in the Fate/stay night visual novel by Type-Moon. It was published by Type-Moon with four volumes released between December 2006 and 2007. The story follows the Fourth Holy Grail War, which is a magical tournament that is held in Fuyuki City, Japan. Seven mages known as Masters must summon Servants, which are reincarnations of legendary souls and heroes from all across time, where they fight in a deadly battle royale where the winner obtains the Holy Grail, a legendary magical chalice capable of granting wishes. The main protagonist of Fate/Zero, Kiritsugu Emiya, joins the tournament on behalf of his wife's family, the Einzberns.