Old Hob was a stray cat that came across the Turtles and Splinter after they were dropped by the pair of ninja that had stolen them from Stockgen. The mutagen that was also stolen spilled, and Hob came into contact with it, causing him to mutate. He tried to scurry off with a pre-mutated Raphael, but Splinter attacked, clawing out one of Hob's eyes. He would later mutate and team up with Baxter Stockman to get revenge on Splinter and the Turtles. Since the mutagen Old Hob came into contact was contaminated, he was sent to bring in the other mutants dead or alive in order to get mutagen samples from their blood. He was put in charge of a street gang and tried multiple times to take down Splinter and the Turtles.