Bull mini-game in Survival mode:
Finish Scene 8.
Eye mini-game in two player mode:
Finish the Eye mini-game in story mode.
Cake Battle mini-game in two player mode:
Finish the Snowball Fight mini-game in story mode against the girl.
Swimming On A Tree mini-game in two player mode:
Finish the Swimming On A Tree mini-game in story mode (save the girl from the crocodiles).
Table Hockey mini-game:
Finish the Disk part of story mode.
Finish Scene 16.
Snowball Chase mini-game:
Finish Scene 23.
Another Story mode and Sound Test:
Finish story mode.
Press Down + Y at the title screen to record from the microphone. Press Down + Y at the title screen again to play back the recording.
Bonus gloves in Maniac mode:
Have the GBA games Sonic Advance or Sonic Advance 2 in your DS to unlock the Pink Gloves, or get 55,555 heart points. Have Sonic Battle in your DS to unlock Amy Rose's gloves, or get 77,777 heart points. Have Chu Chu Rocket in your DS to unlock the Fist gloves, or get 88,888 heart points.
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