I have just realized that Scott left at least one hint in each trailer of the games... And yes, that took me awhile to notice them.
Then I found a character that made a mystery appearance in Five Nights at Freddy's 2. Also, Old Bonnie's position struck me this reason, straight from the trailer, at least.
And third, I picked up the one from trailer in Five Nights at Freddy's 3.
First one, which showed us Bonnie removed his head part have prove that he experienced being faceless in prequel. While the new one that Luigi had just discovered, which showed us that Springtrap stood in same way Bonnie did, but thirty years later.
Second one, which showed us Bonnie's alternate animatronic; "Shadow Bonnie", make a hint of their predecessor being returning in the sequel's arrive.
And now third one had us with Springtrap's twisty position that show us Purple Guy being alive, but suffered the nightmare that he fought against the Animatronics in his own twisty images!
Well played, Scott! Well played!!