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Wait, what? So, did the bodies suddenly disappeared, nobody noticed blood on animatronics or just the smell or what? This doesn't makes any sense. First one is possible considering how much weird stuff (including Golden Freddy) is happening in the games, but not others.
What he does in the first game (teleporting into the office) also applies to 2nd and 3rd game (except he doesn't attacks in 3rd one and he also lacks that burnt appearance that Phantoms have, so, maybe he isn't one). I know that fifth child is in the Fredbear, but i don't think he still remains here like others.
I know about that. But sharp teeth always were here (and they are present on Foxy), so, its more of an issue.
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Have another screencap
FNAF1 again: (brightened so it's easier to read)
So yeah, there was some pointers that they were in the suit. Now it's entirely possible that those are the remains from Phone Guy and the night guards that came before Mike Schmidt (Night 3's phone call says congratulates you on making it that far claiming that most night guards don't last that long), but considering the evidence in the minigames for 2 and 3, I'd say it's more likely those are the kids' remains.
As far as Golden Freddy showing up in FNaF3, there's pretty strong evidence that he's now Phantom Freddy. Compare these rips from the games.
Golden Freddy in FNaF2Phantom Freddy in FNaF3Note how Phantom Freddy is missing the same ear as Golden Freddy, has the exact same mic, and has wires sticking out of him like that. Some people argue that the mysterious Freddy hallucination in the office in FNaF3 is Golden Freddy, but as the game is naturally green tinted, people have found that removing the green tints makes Freddy look Purple (like Shadow Freddy).
I'll answer the Mangle bit in the next part.
Makes sense. Still don't understand why no one fixed the glitch once its been found out what they do at night (someone should have been stuffed into the suit first for Phone Guy to hear/know about it because thats not the first thing you think about when hearing about animatronics walking around at night and attempting to harm the night guard) in such case.
Oh this one's actually pretty easy to answer. The FNaF1 phone call on Night One details that the company will not take responsibility for damages to its staffers, and that if anything happens, they'll just file a Missing Person report and bleach the carpets. They also state that they NEED the animatronics to walk around at night or their servos lock up.
If that sounds messed up, in FNaF3, Night Three's phone call instructs that if someone gets caught in a springlock malfunction to make sure that they make it to the "safe room" so that they can bleed out without customers seeing them (although on Night Four, they discontinue the suits after multiple springlock failures happen.
In short: they just don't give a shit unless it drives customers away, so I'm sure they're not worried about kids playing with exposed animatronic parts that have sharp teeth, nor do they care about their employees getting shoved into suits.
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I see your point, but the only thing that that really proves is that the restaurant has masks for the kids to wear. Any kid can wear a mask. And again, that doesn't really address the fact that their bodies are too big to hide inside the animatronics with all the wiring and endoskeletons. At least not in such a way that their bodies would never be discovered.
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This is mostly guesswork, but if you notice the Game Over screen in FNaF1, it can comfortably fit a grown man, and the only real giveaway that there's a person in there is that his eyeballs are hanging out in front of the suit. While it's hard to guess due to the Atari-esque nature of the sprites, it looks like you could fit a kid in the belly of one of those suits.
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That's only if you're assuming that Fredbear was immediately replaced with Freddy Fazbear at the time when they rebranded the place. That "Fredbear and Friends" cartoon easter egg suggests that that cadre of characters existed at least as far back as 1983.
Also worth considering: The company that actually runs Fazbear's has been pretty consistently portrayed as not giving a hard boiled shit about things like safety or maintenance or spending a single dime more than they absolutely have to on that restaurant. It's conceivable that after they made the shift from Fredbear to Freddy they just kept using the Fredbear stuff as long as they possibly could in order to cut costs, and just sold it as "Golden Freddy."
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If FNaF4 takes place before '87, then that's probably a good enough reason to rebrand as fast as possible.
Holding onto Fredbear for that long and selling it as Golden Freddy in 1987 wouldn't work though. Recall that in FNaF2 on the Night Six call, Phone Guy refers to him as merely "a spare in the back, a yellow one." This is especially odd for Phone Guy since he seems to be one of the higher ups in the company based on his calls in FNaF2 and 3, and he can only barely remember the name of the restaurant they bought out. Another thing to keep in mind: by the time FNaF2 happens, the chain has gone through two changes: Fredbear's Family Diner -> Fazbear restaurant we never see -> Freddy Fazbear's Pizza in FNaF2. As there is an old Freddy Fazbear animatronic that exists for that second restaurant, it would be really weird to have both simultaneously.
And like I said above, they are frugal with their spending IF it doesn't have a negative impact on the customers. So yeah, I'm sure they know they wouldn't fool anyone if they put Fredbear out there and tried to convince people that it's really a Golden version of their mascot.