- Sega Genesis reference
Fly to the top of the building that is at the bottom-left of the map in Metropolis. Fight (or flee from) the Seeker Drone, then continue to find a Sega Genesis. There is a controller beside the machine next to the Genesis.

- Completion bonus
Successfully complete the game to unlock the New Game Plus mode.

- Recommended items and Chao
The following is the recommended items and Chao for each character:

Sonic	Speedy Sneakers, Golden Gloves, Spooky Charm, Joy
Big	Economiser, Choopaloo
Shadow	Speedy Sneakers, Golden Gloves, Angel Amulet, Gibber
Rouge	Economiser, Ovus
Dr. Robotnik	Lucky Gloves, Bepke
Cream	Alloy Slippers, Sparkly Gloves, Pretty Dress, Cheese
E-123 Omega	Oily Hydraulics, Titanium Claws, Zoah Shield, Ferox
Knuckles	Swift Boots, Golden Gloves, Voxai Teleporter, Spartoi
Shade	Swift Boots, Golden Gloves, Nocturne Blade, Beglog
Amy	Alloy Slippers, Golden Gloves, Pretty Dress, Hayda
Tails	Speedy Sneakers, Lucky Gloves, Blaze

- Bonus characters
Successfully complete the indicated task to unlock the corresponding character:


- Easily complete Kron Colony
Overcome the first Kron you encounter. Save the game, then go south to an opening. You must fight another Kron. After you defeat him, with Amy in your team, go to the opening west from that area. Once you enter, bash the boxes with Amy's hammer. Go forward, and ignore the Kron. If you get attacked by him, just flee. Go to the next room. Continue until you reach the ruler, then talk to him.