Fate/Zero

The story of Fate/Zero takes place ten years prior to the events of Fate/stay night, detailing the events of the Fourth Holy Grail War in Fuyuki City.[4] The Holy Grail War is a contest, founded by the Einzbern, Matou, and Tohsaka families centuries ago, in which seven mages summon seven Heroic Spirits to compete and obtain the power of the "Holy Grail", which grants a wish to each member of the winning duo. After three inconclusive wars for the elusive Holy Grail, the Fourth War commences.