Nightmare Golden Sonic seems to have a bunch of cloning material melting on him. Only half of his hat is left, and half of his torso, his left leg, a bit of the left side of face, and his left ear are the only parts uncovered by cloning material. His teeth also aren't as wide as his past self's ('27 Golden Sonic's) are. While his eyes are normally white, they usually turn red when killing you (but not in FNaS 5, pupils is still white)