side story 2: the grail

under the Fuyuki mountains,

the greater grail which served as the main power source for the holy grail wars was located over a layline,

deep inside the grail, a small portion of it which has yet to be corrupted by the Avenger, Angra Manyu, awoke from it's slumber

the reason for its awakening, was that someone had broken the rules for the ritual,

it used the limited amount of power it had to find the problem

instead of 7 servants being summoned, 8 servants had been summoned, out of the 8 servants, 4 servants were located in the same place, possibly for an alliance, it also detected that an incarnated servant from the last war was living in the church

the grail required the death of at least 6 servants to enact its omnipotence and grant the wish of the winner

after realising all of the anomalies, it had no choice but to use all of its remaining power to spread out additional command seals and activate the reserve system as per its directive,

the greatest grail war in the history of fuyuki had begun