Sergeant Zarex thought he'd gotten out. He'd hung up his battered armour after the Kreludan civil war and tried to put his days in the top-secret Section Six behind him. But when the mines of Kreludor were suddenly overrun with hostile robots, everyone knew that there was only one Grundo for the job.
Energy readings show incredible activity in the deepest part of Mine Complex 13-A. Since the area is too deep underground for teleportation, Zarex will have to beam into the uppermost chamber and fight his way past swarms of angry machines in order to uncover and destroy the cause of the invasion.