CO Power is a special power that you can activate depending on how well you are doing on the mission. Each CO has 2 Different types, one is a bit weaker then the other. The bar should be half way and you get the first CO power, when it is full, the 2nd CO power should activate. You can active at it when you hear a whoosh noise and the bar should light up.
In the first Advance Wars, there was a bar next to the CO's name that filled up as time passed. Once that bar was full, you could use your CO power. In the second and third games, the series switched over to stars. When you had enough stars, you could activate your CO power. However, if you waited, you had a chance to build up power for a Super CO Power. In Advance Wars: Days of Ruin, the series adopted some bars, which, after being filled by having your CO Zone out for long enough, allowed you to use your CO Power.
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