Periremunda System

The Periremunda System is an Ultima plateau well whose principal world is eighteen thousand habitable mesas over volcanic lowlands. Ciaphas Cain and the 597th landed here for a 'simple' uprising and found genestealers, a Tyranid fleet inbound, and Amberley Vail already on the ground.

The system is a Cain war-story address, not a hive cluster and not a second Tarsis Ultra. Keep the unofficial Ultima pin. The mesas are why anyone can live here at all.

The Periremunda System still matters as a mesa-world that almost became biomass because a commissar's rest stop was a cult. Unofficial summaries keep the Ultima parent and do not invent a Guard homeworld cult here.