Transmutate had a life span of 1 episode, but he was still cool. He was the result of a broken stasis pod running crappy scanners. He couldn't even transform, but he had one of the coolest weapons in the series: his scream. His few words amounted to "Friend, Fly, Hurt." The coolest part of the episode was when Silverbolt wouldn't let Optimus and Cheetor slag Rampage, because, he said they were "brothers."
