Cog Changer (voiced by Michael Sorich) was a robot monster used by the Machine Empire to access Zeo technology. He was capable of replacing the cogs on the Zeo Jet Cycles with evil ones that would cause the Rangers to lose control of the cycles. As such, the Zeo Cycles ended up getting destroyed. He also piloted the Zeo Megazord after knocking it out of the Rangers' control. He later fused with Impursonator.