Also interesting to note that Scott called William "Purpleguy" in his confirmation post and that's how he's called in FNaF World. While talking to Purpleguy in the Halloween world, he talks about not mistaking him "for the actual Purple Guy" -> "Purple Guy". This could mean that William is "Purpleguy" and Michael is "Purple Guy", because Michael is literally a purple guy.
A reference from the FNaF 2 teaser with Withered Bonnie and Toy Bonnie back-to-back.
Implying that kids tore apart Mangle, and that someone didn't dismantle 'em. Also depressed endo.
This one seems the most interesting. Could mean that FNaF 4 took place after FNaF 1 or that Classic Foxy and Nightmare Foxy are the same character, or both.
Implying that Golden Freddy is the one saying It's Me, or is one of the characters that says it.
This is a reference to Markiplier's playthrough of FNaF 4 when he talked about Nightmare Chica making him a sandwhich in the kitchen.
It says that Springtrap is a killer, which mades sense since William is inside him. See, FNaF World confirmed Willtrap.
You know I had to do it.