Play as Super Sonic:
Beat the game with every character and the 7th character; "Super Sonic" will be opened.
Play as Super Knuckles:
Beat the game with all six characters, then beat it again as Knuckles. Then hold X + B at the character select screen.
Play as Tails:
After he is obtained, use Controller 2 to play as Tails.
Put the game disc in a PC CD-ROM drive to find additional art images from the game.
New Twinkle Park Race view:
Press Up on the Twinkle Park Race level to switch views.
Full pause screen:
Press Y + X at the pause screen.
Just before entering the snowboarding part of the game, press "X" for a Blue Board, and "B" for a Yellow Board.
To Get a Metal Chao Baby:
To get the metal Chao Baby go to the mystic ruin and go to the water fall, look to your right and you'll see a platform, push it in and behind the water fall a metal egg will come floating to land. Go to the nearest Chao garden and toss the egg in and it will hatch!
To Get a Gold Chao:
Go to the shop in the first town where the guy tells you not to use the backdoor. Go in the open area where you first fight Chaos and look in the corner with the trees for a gray rock shaped like an egg. Take the rock to the shop and set it down. Pick up the gold egg in the window and the exit will seal off with bars. Take the gray rock and set it where the gold egg was and it reopens the exit. Take your gold egg to the Chao garden and hatch it -- Gold Chao.
To Get a Black Chao:
Wait until Robotnik's ship crashes, then go to the prison (where Amy was being held earlier). In one of the cells there should be a black egg. Pick it up and walk out into the large corridor (the one with the cleaning robots and the trams) and go to the very end. You should reach a teleporter pad. Step onto the pad and you'll be transported to the third Chao Garden with a soon-to-hatch black Chao.
Grab 10 animals from a stage with robots & go to your chao at Station Square, Mystic Gardens & Egg Carrier. Give your chao the animals & keep repeating. Note: Do not hit your chao or it'll never grow into a good racing machine & your chao will vanish & may appear again if you wait until it re-appears.
Thanks to Revolution reader ArtiLiroy, Spencer Welch, Tomahawk Sam, RaVeN 2799, John Lawver, Jonny scully tyus, Axle 47, Mike Le, Sanschel Chris B, Brendan "Computer Wiz" Backhaus and Kevin!