View pictures:
Press Select while in the sound room. You will be able to see several pictures from the game. Press Left and Right to cycle through all of the pictures (26 in all) or press B to exit.

In-game reset:
Hold Start + Select + B during game play.

Deleted saved games:
Hold L + Right + Select when turning on the Game Boy Advance.

Nintendo mountain map:
Use the following trick to get to a map with the text "Nintendo" made with mountains. When you are at the selection with: Design Maps-> Map or CO, highlight "Map" and hold A + L + R for a second. The screen will turn blank. After a few seconds. it will be done.
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Japanese character mountain map:
Use the following trick to get to a map with the three Japanese characters made with mountains. When you are at the selection with: Design Maps-> Map or CO, highlight "Map" and hold L + R for a second.

Sound Test:
Win a campaign under the normal difficulty setting with an any rank to unlock the Sound Test at the store.

Gallery:
Win a campaign under the hard difficulty setting with an any rank to unlock the Gallery option in Sound Test.

Adder:
Successfully complete all the Black Hole campaign levels to unlock Adder at the store.

Colin:
Buy Grit or Olaf at the store.

Drake:
Successfully complete all the Green Earth campaign levels to unlock Drake at the store.

Eagle:
Successfully complete all the Green Earth campaign levels to unlock Eagle at the store.

Flak:
Buy Flak in Battle Maps.

Grit:
Successfully complete all the Blue Moon campaign levels to unlock Grit at the store.

Hachi:
Successfully complete all the hard mode campaign levels and buy everything in his store to unlock Hachi.

Hawke:
Successfully complete all the Black Hole campaign levels to unlock Hawke at the store.

Jess:
Buy Drake or Eagle at the store.

Kanbei:
Successfully complete all the Yellow Comet campaign levels to unlock Kanbei at the store.

Lash:
Successfully complete all the Black Hole campaign levels to unlock Lash at the store.

Nell:
Successfully complete all the campaign levels to unlock Nell at the store.

Olaf:
Successfully complete all the Blue Moon campaign levels to unlock Olaf at the store.

Sensei:
Buy Kanbei or Sonja at the store.

Sonja:
Successfully complete all the Yellow Comet campaign levels to unlock Sonja at the store.

Sturm:
Get an overall "S" rank in campaign mode.

Sound Test:
Successfully complete campaign mode with any rank to unlock the Sound Test at the store.

Gold campaign menu icon:
Successfully complete all levels in normal and hard campaign mode with an overall "S" rank.

Gold design room menu icon:
Buy everything from Hachi's store.

Gold link menu icon:
Get the war room, versus mode, campaign, design room, and battle maps flashing gold to unlock the link mode to flash gold.

Gold versus menu icon:
Play all maps in versus mode. Note: You do not have to win on each one.

Gold war room menu icon:
Successfully complete all maps in the war room with an "S" rank.