Mr. Snuff is a pink fat gastropood alien, who speaks Flatula. He is voiced by Dee Bradley Baker.
Mr. Snuff is a fat yellow alien who resembles a slug, but with the exception of his strange tentacles (which serve as two pairs of arms and are also found in the form of 2 rows on his back) and his trunk-like snouts, both of which emit strong flatulent noises as his form of communication. Doppler is able to understand and communicate with him, having taken two years of "Flatula" (a language class that involves making flatulent noises, hence the name) in high school, which he demonstrates when he manages to reason and joke around with Snuff after Jim accidentally steps on part of his tail. He has suction cups for feet, which are hidden underneath his flabby body and tail, and they come in handy sticking to the Legacy's deck in times that the ship lacks gravity. It is unknown whether or not Snuff was part of John Silver's crew or what had happened to him in the film; he is last seen with some of the pirates observing their arrival to Treasure Planet, but as soon as Silver initiated the mutiny, he mysteriously disappeared and was never seen again throughout the rest of the film.