FATE/ZERO Episode 1
FATE/ZERO Episode 2
FATE/ZERO Episode 3

This is the first episode of FATE/ZERO, the prequel of Fate/Stay Night telling the story of the 4th Great Holy Grail War. The Holy Grail War is a battle to death between seven Masters and their Servants which are Heroic Spirits of legend. They have seven different rank in order to be summoned more easily: Saber, Archer, Lancer, Rider, Caster, Assassin, Berserker.

Confirmed Servant and their real names:

Servant Saber: King of Knights, King Arthur
Servant Archer: King of Heroes, The First King - Gilgamesh
Servant Lancer: The Knight of Fianna, Diarmuid Ua Duibhne
Servant Rider: The Lord of War, The King of Conquerors - Alexander the Great
Servant Caster: Gille de Rais, Bluebeard
Servant Assassin: Old Man of the Mountain, Hassan-i-Sabah
Servant Berserker: Knight of the Lake, Sir Lancelot