The Grail is broken. The failure of the Einzberns in the Third Holy Grail War has created a shift, and Avenger is ready to cause chaos. As Fuyuki prepares for its Fourth Holy Grail War, a second, alternate one is set to begin: battle comes for Winterbaum, and this time, the prize is different. The First Moon Cell War dawns. For some, it spells hope. But, maybe for all, it is doom.