Curse mark Sonic resembles a lot compared to perfect nazo. He has dark black fur and a red curse mark on his forehead. When powering up the curse mark shines black and his fur looks red and Sonic looks like shadow about to preform chaos blast
Curse mark Sonic has abilities like Shadow he can teleport, fly, and use moves like chaos control and chaos blast. If he runs as fast as Hyper Shadic he will become a flaming ball of fire and can destroy anything in his way.
Sonic becomes Curse mark Sonic when he breaks into Eggman's lair and is shot by a laser made by Eggman's grandfather that turns one cursed to become a judge of justice. He can not become normal unless he kills the G.U.N officer that killed Maria. Eggman's grandfather wanted to shoot Shadow when Maria died but Maria shot him to Earth.
Curse mark Sonic resembles Ghost Rider who judges what people and makes them see what they have done wrong
Sonic can choose to be Curse mark Sonic at night and can do it in the daytime if he collects all the chaos emeralds