Clown

Clowns are creatures evil and playful.

Season 2
Sam and Dean investigate a series of murders that have occurred while a circus is in town. A clown has been seen in the vicinity of the deaths. Dean teases Sam about his fear of clowns: "you still bust out crying whenever you see Ronald McDonald on the television".

The boys start investigating Cooper's Carnival and their suspicions are aroused after a little girl sees a clown her parents can’t see. They stake out the girl’s house, and manage to save her from a clown, who disappears as they shoot at it. Sam calls Ellen, who tells the boys the creature is a Rakshasa that must be killed with a brass dagger. Suspecting Mr Cooper, the carnival owner, the boys return to the circus. The real culprit is the blind knife thrower, who attacks the boys and traps them in the funhouse. Sam manages to kill the Rakshasa with a brass pipe from the organ.

Season 7
Howard is using Hoodoo to exact revenge on people he perceives as mean or neglectful parents. Howard takes a drawing of the child's fear, which the restaurant chain encourages them to do on placemats, and combined with an object owned by the parent. There is power in the child's fear, and combined with the spell, it manifests in reality.

When Sam and Dean arrive in Wichita, Kansas, Sam is reluctant to go to Plucky Pennywhistle's Magical Menagerie and Dean teases him that it's because of his clown phobia. Sam denies it, but is obviously uncomfortable when he is confronted by all the clowns at the restaurant. Another employee, Cliff, tells Dean and Sam he and Saul heard noises coming from the sub-basement. When one of the waitresses Libby berates her son Tyler, she appears to be the next victim. Sam follows, on the lookout for the giant robot with laser beam eyes (Tyler's fear). Dean goes to the sub basement, and finds Howard's hoodoo books and equipment, including a cauldron with a fire in it. Howard confronts him, and tells him he's put a spell on Sam. As Sam watched Libby and Tyler, he is approached by two evil-looking clowns, who attack him. Dean manages to get a clown statue Howard owns, along with a drawing he did of his brother drowning, and tosses them into the fire. Howard's drowned brother appears, and Howard "drowns". His death causes the clowns attacking Sam to disappear in a shower of glitter.

Afterwards, Dean apologises to Sam for leaving him at Plucky Pennywhistle's Magic Menagerie when he was a kid, assuming that's where Sam's clown fear comes from. Sam says that fighting the nightmarish clowns was "therapeutic". But when Dean gives him a toy "Plucky Pennywhistle" calling it his "clown phobia sobriety chip", Sam grimaces, and throws it out the window as they drive off.