Super hard difficulty setting:
Successfully complete the game under the hard difficulty setting. Start a new
game, and the super hard difficulty setting can now been selected.
Wario Karaoke:
Enter the sound room and highlight the "Exit" option. Press Select + Start +
R + L + Up to unlock Wario Karaoke. Alternately, get gold crowns by collecting
over 10,000 coins in all levels to unlock the Wario Karaoke (music test)
option.
Wario Karaoke control:
Press Up or Down to change the pitch of the song. Press Left or Right to
change the tempo of the song. Press L or R to toggle between a green CD,
yellow CD, or just the lyrics.
Sites: