Zhao-Arkkad

Zhao Arkkad is a toxic rainforest death-forge world of Segmentum Tempestus, its forge complexes driven entirely underground. The surface biosphere is corrosive to flesh and metal alike, and the Magi of the world long ago abandoned open-air manufactory halls for deep subterranean works, where ore and promethium are refined away from the poisoned canopy above.

During the Horus Heresy, Zhao Arkkad pledged its forges to the Thousand Sons and despatched war engines to reinforce Prospero, binding the death-forge’s fate to that of Magnus the Red’s Legion at the height of their rebellion. The alliance drew the world into the wider war: a Dark Angels fleet pursued the conflict into the Zhao Arkkad system itself, fighting the forge world on its own ground rather than leaving it to stand untouched behind the front lines.

The Scouring that followed the Heresy brought Zhao Arkkad back under Imperial authority, as the Dark Angels and their allies rolled back the Thousand Sons’ remaining footholds across the Segmentum. Nominal loyalty was restored, and the forge world resumed its place within the Imperium’s manufactory network, its underground works continuing much as before under renewed oversight.

That restoration was never complete in spirit. The Magi of Zhao Arkkad were ordered to scrap their Xestobiax-pattern Titans as a condition of readmission, yet accounts agree that entombed war engines of this pattern remain within the world’s deep vaults rather than having been destroyed. Their survival, quietly tolerated or quietly concealed, stands as the clearest surviving sign of Zhao Arkkad’s old loyalties and an unresolved thread in its long return to the Imperial fold.