At Chaldea Security Organization, the final Master of humanity Ritsuka Fujimaru and his Servant Mash Kyrielight have journeyed through six regions of differing eras in order to retrieve their future lost due to the "incineration of humanity" caused by the Mage King. And now, to repair the final Singularity, the pair head forth into ancient Mesopotamia. As soon as they land in those lands where the gods exist on an everyday basis, they are assaulted by an overwhelming number of Demonic Beasts. And just as suddenly, a beautiful girl descends down from the sky.

Fujimaru, Mash and the goddesses enjoy one last moment of peace on the eve of the final battle. That same night, Kingu reaches the peak of the ziggurat. So badly injured that he can no longer stand, he looks up to see a figure looming over him... As morning dawns, King Gilgamesh gives Fujimaru and his companions some final words of encouragement. Their attack on Tiamat begins now!