Clayton

Clayton is a recurring student in Miss Simian's class at Elmore Junior High in The Amazing World of Gumball. He is a red ball of clay who can shapeshift into anything, and a compulsive liar with a habit of inventing absurd stories about his life; the fan wiki adds that he can disguise himself as other people and mimic their voices, and that his lying comes from finding himself boring and socially awkward. He was voiced by Rupert Degas in season 1 and by Max Cazier from season 2 onward.