The Low Kryten was a version of Kryten created by the triplicator.
Low Kryten
This Kryten was a malfunctioning, twitching mechanoid covered in grease. He wore a spiked collar and gloves and thought nothing of punching through a wall (in a manner reminiscent of RoboCop) to attack the original Lister.
He twitched and stammered when speaking and seemed devoid of the original's moral fortitude. He was sadistic and callous, enjoying the violence that he inflicted on others. He inserted a spinal implant into Lister's neck to control his actions.
He was destroyed when the two versions of Red Dwarf were combined to recreate the original. (RD: Demons & Angels)