Greg (voiced by Collin Dean) is the younger half-brother of Wirt. He is energetic and imaginative, acting as a sort of optimistic antithesis to Wirt. He is short and plump, wearing a pair of faded green overalls, matching black shoes and a brown satchel over a white shirt with a ribbon. Unlike Wirt, he is often unconcerned in the face of danger; for example, he gleefully follows the instructions of the Beast, unknowingly defying the Beast's intentions to exhaust his strength. He wears a tea kettle on his head so as to resemble an elephant for Halloween.
