Hold Start + Select + B during game play.

Hold L + Right + Select when turning on the Game Boy Advance.

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.

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.

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.

Advance Wars 2 Unlockable Characters:

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

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

Buy everything from Hachi's store.

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

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

Successfully complete all maps in the war room with an "S" rank.

The map to the secret lab level is in the unoccupied building across from Lash's headquarters in the Toybox level. Note: You must capture the city in order to get the map.

In the inking Feeling level, the secret map is found in the city in the southern-most city on the Western Isle. Note: You must capture the city in order to get the map.

In the Flak Attack level, capture the city that is located about two squares above your headquarters.

In the Show Stopper level, the secret map can be found in the southwestern most neutral city. Note: You must capture the city in order to get the map.

Find one of the Black Hole Army maps. Finish the missions that the map gives you. You will be able to build Neo-tanks, with only that country. This is also helpful for future missions in which you can use COs from other nations.

On the final mission, you are prompted to chose an Orange Star, Blue Moon, then Green Earth CO. If you wish to use a Yellow Comet CO, press Up or Down until you get to it at the CO select menu.

If you defeat a country's factory but do not have the money to buy any COs or maps, just restart the campaign. None of your early COs or maps will be gone. You can replay the campaign and do all the easy missions and get about 300 points every time then easily buy the COs and maps.

If you are having a difficult time winning battles where you start with nothing but a couple of bases, try these tips. Capture the farthest base or airport as soon as you can. Anti-air guns are very effective at stopping enemy units from capturing bases. Do not be afraid to capture a base if one of your units are damaged.

Using Sensei's power, your infantry, or even better, mech units, can combine. However, 8 HP is not exactly lost. It gets converted into funds which can build up. Also, watch your opponents; direct the unit's ammunition. You can force them to run out of their primary ammo by attacking them with the correct unit.