The “Moon Holy Grail War” begins again... After humanity discovered a supercomputer hidden on the moon, everything changed. Known as the Moon Cell Automaton, this powerful computer created SE.RA.PH, a digital world where 128 combatants are pitted against each other for the ultimate prize, the Holy Grail. An omnipotent wish-granting device, the Holy Grail is capable of fulfilling any desire. Now in the role of Masters, these combatants form contracts with Servants, digital beings embodying historical figures and heroes, hoping to be the final victor in this life-or-death battle.

 Having lost all memories, unable even to recall why they’re trapped inside this virtual battlefield, one such combatant is thrust into the role of Master and must step into the grueling Moon Holy Grail War alongside a single Servant, driven solely by the will to survive.