As Omega is attacked by Adjutants, Colonel Raymond Ashe and General Oleg Petrovsky arrive aboard the Elbrus and destroy the remaining Adjutant-controlled Cerberus transports. During the cleanup aboard the station, Ashe orders Aria T'Loak's mercenaries to finish the job and kill those who were wounded before they can transform into Adjutants themselves. Aria takes offense at Ashe disrespecting her authority so visibly and hits him with a biotic attack. Later, while Aria and Petrovsky oversee the defense of Omega from the Elbrus, Ashe is kept on the station in chains until the crisis is over. As Ashe's guards taunt him, he intimates that he's right where he needs to be. He kills the guards, then contacts the Illusive Man to inform him that he is ready for the real battle for Omega. He quickly slaughters everyone in Omega Control so that no one could be alerted to the arriving Cerberus reinforcements. He then broadcasted to all of Omega, declaring a coup and demanding that everyone submit to Cerberus for their own protection or suffer the consequences.
Initially, after Aria T'Loak is taken aboard the Elbrus to Cerberus's Avernus Station beyond the Omega 4 Relay, her allies assume that she has been killed. Realizing the power vacuum, Omega's gangs go to war with each other. In the chaos, Ashe commands the Cerberus forces on the station as they move in and attempt to secure it. Aria is able to return, however, and quickly coordinates the gangs to fights against Cerberus. With Petrovsky also back to take command of the situation, Ashe is criticized for his lack of consideration for Cerberus and civilian casualties.
The growing rift between Petrovsky and Ashe comes to a head when Ashe uses an Adjutant to attack Aria and her men within the Afterlife Club. Petrovsky is outraged that Ashe would place everyone on the station in danger by letting an Adjutant loose, but Ashe counters that they are acceptable losses. They begin to fight, but are interrupted when Aria flings the Adjutant at them. While Ashe tries to shoot her the Adjutant infects him. As he begins to transform, Ashe asks Petrovsky what he will do. The General says he will protect his men, and shoots Ashe in the head. In his report to the Illusive Man, Petrovsky claims that Ashe is missing and assumed to have met the end he deserved.