Apocalypse tanks were deployed during the initial invasion of the United States (several were seen in San Francisco when the Allies traveled back in time to stop Yuri).
The Apocalypse tank was the most powerful tank in the Third World War. It possessed a pair of powerful cannons effective against both vehicles and structures and was capable of eliminating the IFV and other light vehicles with a single volley. Against infantry, the cannons were significantly less effective, doing relatively minor damage. The Apocalypse also featured dual Mammoth Tusk missile launchers, effective against enemy aircraft. Lt. Zofia described them as “war in a can”. Like the earlier Mammoth tanks, the Apocalypse was designed to go toe-to-toe with any enemy unit, and emerge the last unit standing.