Nikaea System

The Nikaea System is a star system in the Segmentum Solar that the Emperor terraformed to host a council of the Legions on the status of psykers. The council met in an amphitheatre constructed for the purpose, and the system is accordingly known as the Council world.

The edict that followed the debate prohibited sorcery, imposed restraints on the Librarius, and instructed Magnus to cease his practices. Magnus did not comply. A later search for a shard of Magnus brought the Thousand Sons and the Space Wolves back to the same site.

The system remains significant because the Imperium’s law concerning psykers originated there. Fan summaries distinguish it as the Council world, not as one of the agricultural worlds of the Segmentum Solar, and unofficial compilations retain the Segmentum Solar as its parent region.