Clyde is a racehorse who is Marvin's younger brother (even though he is now bigger than Marvin). He appeared in "Marvin Keeps Track". He and Marvin used to do great things together when they were young and Marvin was always the winner, but now Clyde always beats Marvin. Marvin was not pleased to see him because he had forgotten all about their past, but then Clyde reminded him. So if not for Marvin, Clyde would've never been a racehorse.