King Komodo is a Mutant Komodo Dragon, who refers to himself as Go-Komodo's "half brother". At one time, he was just one of Go-Komodo's pets, but he was accidentally injected with a synthetic Mutagen during the Turtles' rescue attempt of Splinter, but in fact, he had already been purposely injected prior to that with Mutagen mixed with Go-Komodo's DNA. Believed to have been killed by Donatello's blowing up of Go-Komodo's mansion, he was rescued and trained by Pimiko.