Clowns

The Clown is a humanoid Monster kept in the Facility. He is listed on the Whiteboard, and is bet on by the Electrical department. He is later released during the Purge and is seen twice.

Physical Description and Attributes
The Clown resembles the stereotypical appearance of a clown; poofy red hair, red nose, colorful makeup, and baggy, multi-colored clothes with frilly trim. He has no outwardly or supernatural features, so the main reasoning behind him being held in the Facility is unknown. Due to his colorful, friendly, and inviting appearance, it may enable him to visit densely populated areas without scaring people, and unwary victims could easily mistake him for a regular circus clown and not suspect his true, violent nature. His joyous pretense is perhaps his most deadly weapon of all.

His preferred method of killing his victims is by stabbing them with a long, curved knife while giggling and laughing hysterically afterwards.

In the Cabin's Cellar, using a fortune-telling machine is what summons him.

Appearances
During the Purge, he is seen mocking Hadley from one of the camera monitors, laughing hysterically as the chaos from the System Purge happens behind him. Later he is seen stabbing an employee of the facility in the stomach, before turning to face a female security guard who is sitting on the ground. She shoots the Clown three times in the chest, but to no avail; the Clown reveals he is bulletproof and is unaffected by the shots.

Trivia

 * Though the whiteboard says "Clowns", only one clown is seen in the whole film.
 * Earlier in the film, when told that that Electrical had placed their bet, Hadley stated "Did you see who they picked? They're practically giving their money away." This seems to suggest that the Clowns are rarely ever summoned to the Cabin.
 * Even though he does not have any supernatural or outwardly characteristics, he does prove to be bulletproof somehow.
 * The Cabin in The Woods at Universal Studios during the Halloween Horror Nights event in 2013 featured a clown named Jack.

Inspiration
The "Evil Clown" is a classic horror trope which stems from the common real-life fear of clowns, or Coulrophobia, as well as the infamous serial killer John Wayne Gacy. Other famous fictional examples include:

The House of Sorority Row, Jack Attack from Demonic Toys'', among many others.
 * Joker from DC Comics
 * The Penguin's minions from Batman Returns.
 * Killer Klowns from Outer Space
 * Pennywise from Stephen King's It
 * The Evil Clown Doll from Poltergeist
 * Killjoy from the movie franchise of the same name.
 * Spaulding from House of 1000 Corpses and The Devil's Rejects.
 * Zombieland where the protagonist has Coulrophobia (fear of clowns) and has to meet a zombie clown during the film.
 * Many movies such as Clownhouse, Drive Thru, The Funhouse, Amusement, Circus Of Fear,
 * Stitches from the horror movie of the same name.
 * Twisty the Clown from American Horror Story: Freak Show.
 * Needles Kane, better known as Sweet Tooth from the videogame Twisted Metal
 * Murder the Clown from the Goosebumps franchise.
 * In the popular horror-survival game Dead by Daylight, one of the playable Killers is The Clown.