Springtrap is most likely an early model of a Bonnie suit (as he is referred to as Spring Bonnie by the Phone Guy). He is a heavily damaged rabbit animatronic of a dirty yellow color. A great portion of his right ear is missing with wires sticking out of the stump left behind.Upon analyzing the three images that can rarely appear when starting a night, it can be seen that Springtrap had no animatronic eyes, but instead has human eyes, though they could be Springtrap's eyes and were simply jammed into Purple Guy's skull when the spring locks failed. This can be supported by the fact that Springtrap's eyes glow, a trait obviously not found in human eyes. It's possible that Springtrap's eyes are actually inside Purple Guy's, making his eyeballs glow. It's also possible Springtrap's eyes are glowing because of a paranormal reason.
Phantom mangle
Phantom Mangle is an antagonist in the game Five Nights at Freddy's 3 and is one of the six phantom animatronics in the game. It is a hallucination of a burned and damaged Mangle.
Phantom Mangle looks much like Mangle did in the second game, but with a burnt appearance, possibly foreshadowing the fire that broke out in the establishment. It lacks eyes, and instead has pin-pricked white irises. Phantom Mangle seems to have half of its left eye missing, although it could just be obscured by something else.