Billy Cobb was a professional MMA fighter and the world's most feared MMA fighter. He was played by real life wrestler, Chris Jericho, and his character was meant for a special guest star appearance. He was featured in the episode "Xero Control" and that will most likely be his only appearance.
Cobb was drugged and then captured by Xero. The Omega Defiance member hoped to try his super suit on the fighter. Xero's suit would learn all of Cobb's fighting moves as Cobb did them and would then give its wearer the abilities Cobb has.
Aaron Stone went to rescue him, but the suit forced Cobb to do combat. The suit learned all of Cobb's moves. Cobb took off the suit eventually while he and Aaron were escaping, but Xero puts on a back up suit he had . Cobb fights off Xero until Aaron and Stan were able to work a device that eventually destroys Xero's suit.
In the end, Cobb visits Jason to tell him that fighters are smart,and not cave men (as Jason believed). Cobb goes on to describe his high class intellect and Jason, fearfully, accepts that people can have brains and buff.