The T-Rex first appeared in the short Cookie Time. His big break came in Sorry, Wrong Era as the main antagonist of the episode where he pursued Jimmy, Carl and Sheen when Hugh played with Jimmy's Quantum Replay 9000 and accidentally sent them back to the late Cretaceous Period. He made his final appearance in the The League of Villains. He later appeared in a few episodes and made a cameo in the Jimmy Timmy Power Hour 2: When Nerds Collide!