Hero Boss Attack: Beat the game with the Hero Side to unlock Boss Attack in 1P Play.Boss Attack is basically a Time Attack to see how quickly you can beat all bosses on the Dark Side. Dark Boss Attack: Beat the game with the Dark Side to unlock Boss Attack in 1P Play.2P Kart Race: Beat either Kart Race Action Stage (Route 101 or Route 280), then beat the other to open 2 Player Kart Race.1P Kart Race: Beat Route 101 or Route 280 to open 1 Player Kart Race.The code is the same for Shadow, except his costume is a red Hucast. Once the versus mode begins Sonic's costume will look like the red Humar from Phantasy Star Online. Go to versus mode, select your stage or versus type, but before that press right and you will see a different picture of Sonic. You will receive a message saying that you have completed all of Sonic's missions and that you have also unlocked a secret costume. Phantasy Star Online Costumes: For Sonic, successfully complete all of his missions (not including Cannon's Core).Green Hill: To unlock a 3D version of Green Hill Zone, you must collect all 180 emblems in the game.Then the Last Side option will be available in Story Mode.

Final Stage: To unlock the Final Stage, Cannon's Core, first beat the Hero and Dark Sides in 1-Player Story Mode.Play as Tikal in VS Mode: Beat all of Knuckles' levels with an A rank.Play as Mecha Sonic in VS Mode: Beat all of Shadow's levels with an A rank.Play as Chaos 0 in VS Mode: Beat all of Rouge's levels with an A rank.Play as Big in VS Mode: Get A ranks on all of Eggman's Stage.Play as Amy in VS Mode: Beat all of Sonic's levels with an A rank.Play as a Chao in VS Mode: Beat all of Tails' levels with an A rank.Finally, go to Sound Test and select 'Character'. After the Credits, go to Stage Select mode, choose any stage and mission and finish it. Select 1P mode, Last story, and fight the Final Hazard again. Main Theme in Sound Test:Complete all three stories (Hero, Dark and Last).Sonic will get a board under his shoes and will be able to street board the level with it! However, you can't complete the stage with this board.

In Sonic's second stage (Metal Harbor), press in the second controller at any time.

Have board in Metal Harbor: First, have two controllers plugged in.

These are cheat codes which can be accessed by inputting button sequences or by various other methods.

Cheat codes music dc