My Top Three Theories of FNAF

1.One very popular theory is that Jeremy Fitzgerald is the victim of the much-debated Bite of '87. On Night 6, Phone Guy says, "Uh, we have one more event scheduled for tomorrow, a birthday. You'll be on day shift, wear your uniform, stay close to the animatronics, make sure they don't hurt anyone, okay?" This leads people to believe that Jeremy did as he was told and, having stayed close to the animatronics, wound up being attacked and bitten by one of them. 

Supporting this theory is the fact that the animatronic characters had been acting strangely recently, having been possibly tampered with. "But the characters have been acting very unusual, almost aggressive towards the staff. They interact with the kids just fine, but when they encounter an adult, they just...stare," Phone Guy says, which may imply that Jeremy, being so close to the animatronics, could have easily made him a target.

2.Another very popular theory is that the night guard for Night 7 - Fritz Smith, according to his termination slip - is actually the Phone Guy himself. Supporters of this theory point out that Phone Guy offers to take Jeremy's shift at night, while Jeremy fills in for the newly-available day shift; Jeremy works on Night 6, so Night 7 theoretically would be the very next night.

On the other hand, Phone Guy states on Night 6's call that they have "one more event scheduled" before the restaurant is forced to close due to an incident, and that he himself would take over the night shift "when the place eventually opens again." This implies that Phone Guy did not begin working the night shift immediately, but rather would begin if and when the pizzeria reopened. It is even possible that there was no guard necessary for that night at all, if the pizzeria closed up that very day - especially if The Bite of '87 occurred during the birthday party, causing a premature shutdown of the establishment.

Furthermore, Fritz's notice of termination states, "First day on the job? Really?!?!" which likely rules out Phone Guy as he has obviously worked for much longer than just one day - unless management considered his first night shift as his first day as it would have been his first time working that particular task.

It is also possible that Night 7 is simply not considered canon, much like the Custom Night from the first game, rendering the identity of Fritz Smith irrelevant to the story at large.

3.

There have been reports of a "Night 8" option appearing on the main menu in rare cases when 

continuing from Night 5. This seems to be a glitch in which the text that normally should read "Night 5" inexplicably changes to "Night 8", and can be triggered by scrolling the mouse quickly over the main menu screen, as seen in this video (via Twitch). When the player manages to click the Night it will show the "1st Night" screen as there is no image for the "8th Night". Since there is no data for Night 8 all animatronics and the Puppet are off, except for Foxy due his broken AI. Once the Night is completed the game will hang on the "6 AM Screen" until you close the game. You can view Night 8 being played here to completion.

Another video that surfaced on YouTube shows the player selecting Night 8 and actually being able to load into it, only to be confronted with Golden Freddy already sitting in The Office, making survival virtually impossible. However, this video was made by a user who is known for fake, edited footage, and thus the video cannot be trusted.

While the Night itself is a programming error, the rumor of Night 8 having any sort of significance to the story is proven false. It is explained how the Night comes about by the Reddit useronevsamillion in his

 post. onevsamillion went into more detail on how this works on this post. This also can occur in FNaF 1 if you do the same actions.

Additionally, this glitch can be used to make the menu read other values, including negative numbers. However, it will not show "Night 0." When completing a night with a negative number, the game will not automatically return to the main menu. Instead, the animated confetti in the background will fall indefinitely.

Tell me what you think.