At one time, Korving and Joy were headed to the ruins of Cyber-Control, which was inhabited by the Cult of C'iva to question their high priest at gunpoint. They hoped to discover what had happened to Golgoth's son and if he could save Mondas and its inhabitants.
As Mondas slowly made it way back to Earth, Korving, the only presumed survivor, accidentally fell into the Cybermen conversion machinery. He became a Cyberman, the first one since the war against Golgoth. (COMIC: The Cybermen: The Ugly Underneath)