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source: https://www.reddit.com/r/fivenightsatfreddys/comments/3dhue0/the_ultimate_foxy_is_a_good_guy_theory/
evidence: well for one he does not directly attack you (see attached images) and so it is to be assumed to mean that he screams to get rid of other animatronics in the room and not that his voice box is broken.
second, after he accidentally kills you he leaves since he knows the others will destroy him if they find out he's a traitor the others will destroy him, and when the others arrive they just stuff you in the Freddy suit
Foxy also bangs on the left door in order to either try to get in and save you or scare away any animatronics inside.
The reason he jumpscares you in the first game is because he's making sure you're safe.
verdict: false
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