In the weeks leading up to the fall of the Confederacy, Mack was heavily involved in the war against the zerg, only to be recalled to Tarsonis to help recover a rogue telepath for the Ghost Program. Along with wrangler Malcolm Kelerchian, Mack and the rest of the unit were dispatched to the southwestern district of Tarsonis City. Unlike the rest of the Division, Mack did not seem to regard Kelerchian in a distinctly unwelcome fashion.
Due to orders from General Ledbetter, the retrieval plan was accelerated, Mack leading C Company alongside B Company against the stronghold of crime lord Fagin, in which the target resided. After an exceptional amount of gunfire and bloodshed, the target was retrieved. In the aftermath however, Mack found himself fighting against the zerg.
With the fall of the Confederacy, Mack has retained his place in the unit, though now in the service of the Dominion Marine Corps.