Gutrot is the Omnitrix's DNA sample of an unknown species from an unknown planet.
Gutrot has the appearance of a mechanical humanoid in a green outfit, with the exception of his head and shoulders being a bluish-purple color. He has four fingers on each hand, which are apparently gloved. Like Water Hazard, he has nozzles/openings from which he can eject gas. He has two on both of his arms, one on each of his shoulders, three on the rim in between his shoulders, three on his head, one on his back and one in the center of his posterior. He has a belt with a window on his stomach so that the gas he uses can be seen.
Gutrot wears the Omnitrix symbol on what appears to be some kind of gas mask in front of his mouth.
Gutrot has a cynical sense of humor and speaks with a gruff tone. He also speaks in what could be a New Jersey accent.