Medrengard: Medrengard is one of the many daemon-worlds to be found in the Eye of Terror, and is the current homeworld of the Iron Warriors Traitor Legion. Like all daemon-worlds, Medrengard lacks many of the normal physical laws, and the planet has been rendered into one giant fortress by the Iron Warriors and their Primarch, Perturabo. Vast towers reach into the ionosphere, dungeons and tunnels and bunkers burrow into the very core and bastions and redoubts bloom like poisonous flowers, blistered with weapons hardpoints and razorwire.
From within, the Grand Companies of the Iron Warriors plot vengeance on the Imperium and plan crusades intended to enslave all before them. Behind the most intricate series of defences and trenches is the Eternal Fortress of the Daemon-Prince Perturabo himself, elevated to daemon-hood for the many atrocities committed by his Legion during the Horus Heresy.
Source: Dead Sky, Black Sun by Graham McNeill, Codex: Chaos, 2nd Edition by various, Codex: Chaos Space Marines, 3rd Edition by various
Submitter: Simguinus
Hive World Terra