Hallucinations are easter eggs in the Five Nights at Freddy's series. They happen randomly, and usually Freddy's face pops up on the screen, along with the text "IT'S ME" and then Bonnie's face with/without eyes. Sometimes, when you start the game, you may see one of these images before the screen reverts to the menu.
Upon viewing the camera and looking at the Parts/Service room you can see Withered Bonnie in a slumped over position similar to that of Golden Freddy. Rarely, if Bonnie has left the room, a figure resembling Freddy but much darker and purple will replace him, in the same position only looking at the camera without turning its head. When this entity is viewed for a long period of time, it will cause the player's game to crash.
RWQFSFASXC, also known as RXQ or Shadow Bonnie, is a hallucination which may appear when the player has lowered the monitor. It has similar effects to those of "Shadow Freddy" except for the fact that it does not appear on the monitor. It made an appearance in FNaF World where it gained an official name, even if it is just a keyboard slam.
A bare endoskeleton may be seen in front of The Puppet's box in Prize Corner. It may also be seen in the Left Air Vent preventing other animatronics from entering the vent, meaning this character may not be a hallucination. This may disprove the fact that animatronics will try to forcefully apply a suit to bare endoskeletons, however this may not be true for these animatronics simply due to the fact that they are newer models. The endoskeleton appeared in FNaF World gaining the name of Endo 02.
Paper Plate Doll
On another rare occasion a paper plate doll will disappear from Party Room 4 and reappear on the wall of the security office. This is purely cosmetic and does not affect any other elements of the game.
On certain occasions you will find hallucinations of black-eyed animatronics. Withered Foxy may appear as one of these hallucinations when you start the game. When you start a night, Toy Bonnie may be seen eyeless as well. Withered Freddy can rarely be seen with black eyes when a night is lost. This, like some other hallucinations, is only cosmetic.
Five Nights at Freddy's 3 doesn't have too many hallucinations like the first 2 games, but there are hallucinations nonetheless. We will not be counting Phantom Animatronics in this list as they are not easter egg hallucinations.
Five Nights at Freddy's 4 has only a few hallucinations.
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