The Ultimate Custom Night Demo is a reskin of Scott Cawthon's first PC game, "Doofas the Dinosaur," which he created in 1989. The changes include a Freddy head on Doofas, enemies changing to various animatronics from the Five Nights at Freddy's series, and gems changing to Mr. Cupcake.

The Ultimate Custom Night Demo has a serious, non-troll version that was previously only available to well-known YouTube stars and was presented by Scott Cawthon. All characters are available for selection in the menu, making the demo essentially identical to the full game. When the player tried to start the night, a message would appear in the middle of the menu, preventing them from going any further if the chosen roster had more than 2,000 points.