Medrengard System

The Medrengard System is Perturabo's fortress well in the Eye of Terror, a daemon-world gravity well under a black star that drinks light. Warsmiths raise kilometre-spires as docks; the primarch sits in the Kolasikon on an onyx isle in a lava lake.

Slaves die in the foundries of Pyriphon. The Iron Warriors have fought each other here as often as they have fought anyone else. This is the IV Legion's Eye fortress, not an Imperial hive.

The Medrengard System still matters as Perturabo's throne after Olympia. Unofficial fan notes keep the Obscurus parent because the Eye punches through that segmentum on this map.