Game Boy Color

Kirby Tilt 'n' TumbleUnlockables08/20/01

Nintendo 64

Mario Party 2Secret Minigames01/09/01
Mario Party 3Hidden Maps05/15/01
Mario Party 3Mt. Mariomore05/15/01
Mario TennisCourts06/17/01

Super Nintendo

Faceball 2000Codes04/15/02