It was a nice, good ol' gloomy day in Atlas. People were freezing, grimm were killing etc.
Suddenly, a fucking wormhole opened. A screeching sound not unlike those of the damned blared so hard that the area around the wormhole disintegrated and it could be heard from the Grimmlands.
Indescribable terrors wrecked their way through the ashes and started killing everything. Trillions (Literally) of madmen began running everywhere and destroying shit while yelling something unintelligible.
And then a gigantic cosmic terror whipped the entire city with its massive dick, rendering it uninhabitable.
The things proceeded to do this for the other cities as well, conquering all of Remnant.
AND EVERYONE TURNED INTO A CULTIST.
THE END