The Super Virus Daemon infected the Super Computer and all of the Guardians including Cardon. As Daemon's infection grew stronger Cardon's Key Tool left him, just like the rest of the infected Guardians.
Cardon led the Guardian Armada into Mainframe with instructions to secure the system so that Daemon could spread her infection there. When his lead ship arrived in Mainframe Bob intercepted it, standing between the fleet and Mainframe's long range guns. Cardon activated a hologram generator in front of his ship to talk to Bob. He tried to convince Bob to lay down his arms and join with them, telling him the only thing that mattered was the Word, and the Word is Daemon.