Advance Warpaper (costs 1 point): Have the Game Boy Advance game Advance Wars inserted.
Advance Warpaper 2 (costs 1 point): Have the Game Boy Advance game Advance Wars 2 inserted.
Hachi's Land map (costs 1 point): Have the Game Boy Advance game Advance Wars inserted.
Lash's Land map (costs 1 point): Have the Game Boy Advance game Advance Wars 2 inserted.
Nell's Land map (costs 1 point): Have the Game Boy Advance game Advance Wars inserted.
Strum's Land map (costs 1 point): Have the Game Boy Advance game Advance Wars 2 inserted.
Bonus COs
Adder (costs 1,000 points): Win Mission 26 in Normal Campaign mode.
Candle (costs 3,500 points): Win Mission 26 in Normal Campaign mode.
Chakka (costs 3,500 points): Win Mission 26 in Normal Campaign mode.
Flak (costs 1,000 points): Win Mission 26 in Normal Campaign mode.
Grimm (costs 1,000 points): Win Mission 20 in Normal Campaign mode.
Hachi (costs 2,000 points): Successfully complete Normal Campaign mode with an overall "S" rank.
Hawke (costs 1,000 points): Win Mission 26 in Normal Campaign mode.
Javier (costs 1,000 points): Win Mission 20 in Normal Campaign mode.
Juggler (costs 3,000 points): Win Mission 26 in Normal Campaign mode.
Kindle (costs 3,500 points): Win Mission 26 in Normal Campaign mode.
Koal (costs 3,500 points): Win Mission 26 in Normal Campaign mode.
Lash (costs 1,000 points): Win Mission 26 in Normal Campaign mode.
Nell (costs 2,000 points): Successfully complete Normal Campaign mode with an overall "A" rank.
Sasha (costs 600 points): Win Mission 20 in Normal Campaign mode.
Sturm (costs 5,000 points): Unlock all other COs, their color edits, and earn all 300 medals.
Von Bolt: Successfully complete Hard Campaign mode.
Zipo (costs 3,000 points): Win Mission 26 in Normal Campaign mode.
Brutal Combat mode
Successfully complete Hard Combat mode to unlock the Brutal Combat mode.
Easy History awards
To get awards quick (for example, "You built 50 Neotanks", etc.), make a map where the enemy is not a threat. Give yourself a lot of bases and cities. Play your map and set the funds to 9500G per city. Start building and you should get awards quickly. If you want to get awards quick for destroying enemies, surround them with units to kill them within Design mode. For example, if you want to get a lot of tanks destroyed, surround a large group of tanks with Megatanks and blast away. Just surround the large group of enemies something that they are weak against.
Easy points
Mission 4 (Reclaim The Skies) in Campaign mode takes only about a minute to complete, and each time it will result in 300 points. After the mission, just save the game in a different file and quit Campaign mode. Load the file for Mission 4 and repeat to get as many points as desired. Note: Make sure to save in the file marked Mission 5 after completing Mission 4. Mission 4 gives you points towards Rachael's CO ranking. Mission 2 is also quick, and is good for getting points for Jake towards his CO ranking.
Hard Combat mode
Successfully complete Combat mode to unlock Hard Combat mode.
Hidden map
While selecting Map Design mode, hold L + R to display a map with terrain that spells "Advance Wars". Also, there are two groups of buildings at the bottom of the hidden map. The orange buildings make the orange star symbol, while the blue buildings make the blue moon symbol.
More bonuses
CO Edit: Reach level 10 or higher with a CO to unlock an alternate costume option in the CO Edit menu.
Gallery (costs 2,000 points): Successfully complete Normal Campaign mode.
Mistwalker: Successfully complete Hard Campaign mode.
Oozium (costs 1,000 points): Win Mission 22.
Soul Of Hachi: Successfully complete Hard Campaign mode.
Soundroom: Successfully complete Normal Campaign mode and buy everything from Hachi.
Wallpapers: Successfully complete Campaign mode to unlock wallpapers for the three COs used most in that campaign at the Display menu.