The Clowns are Billy’s worst fear and and villains in the episode Attack of the Clowns of The Grim Adventures of Billy & Mandy cartoon show. Annoyed by Billy's dread and paranoia of clowns, Grim and Mandy try to cure Billy’s coulrophobia (fear of clowns). The Clowns also made an appearance in The Grim Adventures of Billy & Mandy Video Game.