Collect 20 emblems in single player story or challenge mode to unlock two player Team Battle mode.
Collect 40 emblems in single player story or challenge mode to unlock two player Special Stage mode.
Collect 60 emblems in single player story or challenge mode to unlock two player Ring Race mode.
Collect 80 emblems in single player story or challenge mode to unlock two player Bobsled Race mode.
Collect 100 emblems in single player story or challenge mode to unlock two player Quick Race mode.
Collect 120 emblems in single player story or challenge mode to unlock two player Expert Race mode.
Select a two player mode. Hold X + Triangle when making a choice at the character selection screen. Keep the buttons held through the level selection screen and release them when the game begins.
Collect 141 emblems in single player story or challenge mode to unlock metallic characters in single player mode.
Successfully complete story mode with Team Rose to unlock the Follow Me song.
Successfully complete story mode with Team Chaotix to unlock the Team Chaotix song.
Successfully complete story mode with Team Dark to unlock the This Machine song.
Successfully complete story mode with Team Sonic to unlock the We Can song.
Successfully complete story mode with Team Chaotix to unlock their FMV sequence in the CG Theater.
Successfully complete story mode with Team Dark to unlock their FMV sequence in the CG Theater.
Successfully complete story mode with Team Rose to unlock their FMV sequence in the CG Theater.
Successfully complete story mode with Team Sonic to unlock their FMV sequence in the CG Theater.
Successfully complete the game with all "A" ranks and 141 emblems to unlock the Super Hard difficulty setting.
When you complete one of the story modes, go to the challenge screen. Notice that one of the stages is not there. To play this stage you must get all seven Chaos Emeralds. You can get the Chaos Emeralds by playing the stages before you face the Boss. Get the key for that stage and go to the bonus stage. Then, catch the Chaos Emerald before you get to the end of the bonus stage. Once you get the all seven Chaos Emeralds, you can play the final stage. There is only one Chaos Emerald for each set of levels.
Successfully complete the game with everyone to face Dr. Robotnik in one final battle where everyone is combined to defeat him once and for all.
As Team Rose, break one of the boxes to get Team Blast. Get close to him in Power or Fly formation on the edge. Use it, then change to Fly formation attack until you are not invincible. Do the same thing again with the other box, then keep attacking in Fly formation close to him. If you get hit, get back on the stage and avoid the rest of his attacks. Get the rings and try again. Eventually he will lose his 100 HP on that side. Then as Team Chaotix, the color of his weak point changes, and it will not be harmed by that formation (blue impervious to speed, red impervious to power, etc.). First, change to Fly formation and get the balloons above you without getting hit. Get in Power formation, get in the canon on the edge, and fire at the weak point. Note: You will not get hurt in the canon. Do this again until it is red and switch to fly. Do the same thing as Team Rose until it turns yellow. Repeat Power formation and Fly formation until he is defeated. You are now in front of Metal Sonic as Team Dark. First, get the level-ups for all three characters. Rouge's is in the air and the rest are in the boxes. Attack him in this order, according to color of weak point: red fly, blue power, and yellow power. Power formation does the most damage. It is recommended that you first get a few extra lives for each team including Sonic's for the next Boss if you have a problem getting balloons.
The Metal Madness part of the Boss is easy, but is the longest. Every time he shoots three rounds of a crystal attack counter with Homing Attack. If he uses missiles, use Thunder Shoot. If he goes down below the clouds, he will throw a ship at you. To counter, punch the ship. His last attack is Chaos Control. This attack is unavoidable and does not do any damage. The only attack that hurts him is Team Blast. To use it, counter the attacks and most of all check your rings; it still decreases like the other Sonic games while in super mode.
When you fighting a Team Boss use Blue Tornado on them by choosing the Speed Formation for any Team desired.
After doing a Team Blast, before the words "Team Blast" in the top right corner of the screen disappears, jump and press Square. You will do something similar to the Light Attack in Sonic Adventure 2 Battle and kill all enemies that were not killed by the Team Blast. This only works if there is an enemy to destroy.
Once you obtain a Key, go to the bonus round. In that round, you must chase the Emerald to the end of the round.
When you have many robots, use Team Blast and you will have more than 100 rings because Team Chaotix can get rings from every enemy with their Team Blast.
Enable the metallic characters for Team Rose. Notice that Cheese has no face.
When you select Team Dark and everyone is saying something, look at Omega's eyes. They will be white. Select any stage and use the Analog-stick to look at Omega. His eyes will now be red.
This trick requires a few things. You need to be Team Dark, find a pole which requires a switch to activate or to defeat all enemies around, and have your Team Blast. Get to the pole, use your Team Blast to stop time and destroy all enemies around. Hit the switch or switches and use Tornado Attack at the pole. You will be swinging on a ghost pole.
When playing as Team Rose, after you complete Egg Carnival, Dr. Robotnik will say "Those were just the easy ones boys", instead of "boys and girls".