In M32, the space hulk Da Iron Worm carried marauding orks across the sector. They destroyed Battlegroup Azezel, the Fortress Worlds Armstrong and Velgagrad, and the Forge World of Temaxia, leaving the Ul-Seraph Cluster defenceless. A warp storm blasted Da Iron Worm off course and into the Warp. Scout vessels determined that its course took it into the Dark Marches and it was never heard from again.
Worlds known to exist within the Uhulis Sector include:
- 1: Codex: Space Marines (5th Edition), p. 30
- 2: Imperial Armour Volume Twelve - The Fall of Orpheus, p. 17
- 3: Codex: Imperial Guard (5th Edition), p. 26
- 4: Warhammer 40,000 5th Edition Rulebook, p. 116