Jack is one of the monsters exclusive to The Cabin in The Woods Universal Attraction.
Physical Description & Attributes
Jack resembles the Clowns in appearance, but is very different from them. Unlike the Clowns, he has a more sinister and scary appearance. He is seen wearing grayish white make up on his face with black lipstick on his lips and black eyeshadow under his eyes. He has a wide, evil smile on his face and red hair spilt into three points to resemble a jester's hat on his head.
Inspiration
Jack, like the Clowns, may have been inspired by movies about killer clowns, like Pennywise from Stephen King's It, Killjoy from the movie of the same name, Spaulding from Devil's Rejects, or infamous serial killer John Wayne Gacy.