Wario Land 2 (GBC)

Flagman D.D. minigame:
beat the game with 100%, all treasures and map pieces.


Battle the bosses:
Beat the game with 100%, all treasures and map pieces. Choose a
Boss level, the hold Down and press A at the level name screen.


Secret levels:
(submitted by: _IMP_ [TML])
Once you have completed a final boss go back to level one, this time don't
press anything and Wario will stay sleeping giving you access to a secret
chapter.