Dwell was a world old in human memory, a place of libraries and long-lived seers whose knowledge stretched back to ages before the Imperium. The Battle of Dwell delivered this fragile inheritance into the hands of monsters, for it was the World Eaters and the Emperor's Children who fell upon it, two Legions already sliding into the abyss of their chosen gods.
The assault became a grotesque competition. Where the sons of Angron sought only the red harvest, the joyous butchery that fed their rising thirst, the Emperor's Children pursued a subtler and sicker prize, the perfection of sensation in all its forms, and Dwell's people suffered horrors that neither pure violence nor pure cruelty could wholly encompass. The two traitor Legions goaded and outdid one another, and the world's ancient wisdom burned as an afterthought.
The seers of Dwell, it was said, had glimpsed the coming darkness in their auguries and despaired, for foreknowledge availed them nothing against the tide. When the World Eaters at last withdrew, glutted, they left behind a graveyard of learning, its accumulated centuries reduced to ash and echoes. The galaxy grew a little more ignorant that day, and the two Legions a little more lost to the powers that would soon own them entirely.