Chaos/Legends

Chaos was the name given to the Netherworld of the Force thought to be inhabited by spirits of deceased Dark Lords of the Sith.

The Dark Underlord was said to have been summoned from the realm of Chaos by a Sith acolyte during the New Sith Wars. Upon his final death, Palpatine was thought to have descended into the "madness of the dark side", and presumably endured a tortorous existence in Chaos. Marka Ragnos's spirit was summoned from Chaos by Tavion Axmis and the Disciples of Ragnos, though Ragnos was summarily defeated and returned to the netherworld by Jaden Korr.