Bonus gloves:
Have the Game Boy Advance games Sonic Advance or Sonic Advance 2 in the cartridge slot to unlock the pink gloves in Maniac mode. Alternately, get
Have the Game Boy Advance game Sonic Battle in the cartridge slot to unlock Amy Rose's gloves in Maniac mode. Alternately, get 77,777 Heart Points.
Have the Game Boy Advance game Chu Chu Rocket in the cartridge slot to unlock the fist gloves in Maniac mode. Alternately, get 88,888 Heart Points.
Sound Test:
Successfully complete story mode to unlock the "Sound Test" option.
Another Story mode:
Successfully complete story mode to unlock the "Another Story" option.
Hair Color option in Maniac mode:
Find 10 Rabbits.
Studio option in Maniac mode:
Find 30 Rabbits.
Bull mini-game in Survival mode:
Complete Scene 8.
Cake Battle mini-game in two player mode:
Complete the Snowball Fight mini-game in story mode against the girl.
Eye mini-game in two player mode:
Complete the Eye mini-game in story mode.
Swimming On A Tree mini-game in two player mode:
Complete the Swimming On A Tree mini-game in story mode to save the girl from the crocodiles.
Table Hockey mini-game in multi-player mode:
Complete the Disk part of story mode.
Seashells mini-game in multi-player mode:
Complete Scene 16.
Snowball Chase mini-game in multi-player mode:
Complete Scene 23 in story mode, where you chase the girl.
Skip story mode level:
Tap the blue button at the lower right corner of the "Start/Quick Start" menu that appears before a level. Tap the yellow button that appears. Tao the small button that appears, answer "Yes" to confirm three times. This can only be done one time per difficulty setting during story mode.
Birthday greeting:
The girl will greet you by saying "Happy Birthday" at the main menu on the date that you entered as your birthday in the system settings.
Holiday greetings:
Set the system date to December 25, January 1, and other holidays to hear a new greeting from the girl.