At some point, a colony of Reaper creatures known as Adjutants broke loose on Avernus Station, overwhelming the personnel. The Adjutants reach the transport ships docked at the station and cross the Omega 4 Relay, arriving at Omega. Some Cerberus operatives manage to survive the initial outbreak on Avernus and flee to the station's exterior, in the hopes that the high levels of cosmic radiation will kill the Adjutants; they are proven wrong, and the Adjutants follow them. They are saved by the timely arrival of the Elbrus, a Cerberus warship commanded by General Oleg Petrovsky. Petrovksy and Aria T'Loak assist the troopers in eliminating the remaining Adjutants and re-securing the station.
- Lake Avernus is a volcanic crater lake in southern Italy, believed by the ancient Romans to be the entrance to Hades.