The Reaverlord Crucius was a Genestealer Cult Patriarch whose Cultists infested the Imperial Hive World Khollorn VII. The world later fell to an invasion by the Tau Empire's Sept World Vior'la, who then began pacifying Khollorn VII's population. The Reaverlord commanded the Cult to attack the Tau, and the Cultists swarmed Vior'la's surprised Fire Warriors. As they began butchering the surrounded Tau, however, the Fireblade Tay'ama was able to rally a group of survivors to him, and they successfully tracked down and killed the Reaverlord. The Patriarch's death caused the Cultists' attacks to lose their cohesion, and Vior'la's forces were then able to destroy the Genestealer Cult.