Fate/Grand Order: Singularity VII - Babylonia

The seventh chapter of Observer on Timeless Temple. The protagonist and Mash are Rayshifted to ancient Mesopotamia in the Age of Gods. Here, they find King Gilgamesh, as well as several other Servants under his leadership, at odds with the Three Goddess Alliance, who seemingly seek to destroy humanity using forces of demonic beasts.

2655 B.C.E. The seventh Grand Order. This is the age when humans and gods first parted ways. The Three Goddess Alliance, formed to destroy humanity. A prophecy of destruction threatening to consume Uruk. Facing ultimate demise, your greatest battle begins!