Press Start + Select + B + A during game play. Note: Do not use this while the Game
Boy Advance is linked to a Gamecube or it may cause data loss.
Deleted saved games:
Hold L + Right + Select when turning on the Game Boy Advance.
Hold B during your turn.
Glowing field training:
To make the field training glow bright flashing gold at the beginning of Advance
Wars, get an "A" rank on every mission in field training.
Advance campaign mode:
Successfully complete campaign mode. Enter the battle maps screen and buy the
"Advance Campaign" item for one coin. Hold Select and select campaign mode to begin
and advanced campaign, with a more difficult CPU opponent.
Field Training bonuses:
Successfully complete field training mode to unlock the "War Room", "Campaign",
"Design Maps", "Stats", and "Special Intel" options.
Quickly finish Field Training:
Select the final battle in Field Training. Win that battle to quickly unlock all
options that normally require Field Training to be completed.