Kidd

A former Zi-Fighter and Amy's former lover, Kidd was soundly beaten in a championship battle and left the league. He returned with a Holotech Saber Tiger, an unusual Zoid that had the ability to turn invisible and conceal itself from sensory detection. Using the Zoid, he went on a rampage, attacking other Zi-Fighters. He was able to destroy many Zoids including two Blade Ligers, the Dark Assassins' Killer Spiner, and Sigma's Boldguard before being stopped by the Mach Storm team.

(Source: Wikipedia)