A senior member of the Inquisition on Terra, Rassilo was greatly respected and powerful. However, upon learning of the failings of the Golden Throne she became part of a scheme to recruit help from the Dark Eldar to repair the vital construct and save the life of the Emperor. She smuggled a Dark Eldar Haemonculus onto Terra, but it promptly went rogue and began conduct its own ritual killings. Rassilo, the Custodian Ephoroi agent Navradaran, and the Inquisitor Erasmus Crowl all began to hunt the creature underneath the Imperial Palace. Battle was joined between Rassilo and her followers and the Custodes and Crowl's Retinue and ultimately the Haemonculus was slain and Rassilo's plan foiled. She attempted to explain her actions to Crowl, but he nonetheless condemned her as an enemy. Rassilo was able to flee but was later found by the Custodes and disposed of.
- 1: Vaults of Terra: The Carrion Throne (Novel), Chapter 25
- 2: Vaults of Terra: The Hollow Mountain (Novel), Chapter 2