CO Power Meter, sometimes called Star Power or CO Gauge in certain games, is a meter that has certain effects. The mechanics of the Power Meter varies upon games.
Advance Wars 1[]
Advance Wars 1 has a CO Power Meter. While the CO Power Meter looks the same for each CO, the charge length differs per CO.
The rate the Power Meter charge is based on the amount of funds damage. Offensive damage delivered to the opponent increases the bar by 25%. Taking damage, however, increases the bar by 100%. This includes counter-attacks as well.
The following will NOT increase CO Power Meter, also known as non-battle damage:
- Deleting your own unit to destroy it.
- Air and Naval Units running out of fuel.
- A unit inside a transport unit.
- Joining.
- CO Power damage (i.e Drake's Tsunami and Sturm's Meteor Strike).
Due to having just 1 bar, the rate of CO Power Meter are separated in 4 different tiers:
| Speed | Funds | COs |
|---|---|---|
| Fastest | 25000 | Sami |
| Fast | 30000 | Nell, Andy, Max, Olaf, Grit, Sonja |
| Average | 40000 | Drake |
| Slow | 50000 | Kanbei, Eagle, Sturm |
Once the Power Meter fills up, you can activate a CO's CO Power. Once used, the bar decreases back to the default 0. You cannot increase your Power Meter during this time until your next turn.
Each time a CO Power is used, the Power Meter values increase by 20% each time, for up to 280%. Once used for the 11th time or more, it will constantly be at 200%. The current values are as follows:
| Uses | Percentage |
|---|---|
| 1 | 100% |
| 2 | 120% |
| 3 | 140% |
| 4 | 160% |
| 5 | 180% |
| 6 | 200% |
| 7 | 220% |
| 8 | 240% |
| 9 | 260% |
| 10 | 280% |
| ++ | 200% |
Advance Wars 2: Black Hole Rising[]
Most of the mechanics remain the same with Advance Wars 1. This game adds another form of CO Power: Super CO Power.
The biggest change is the introduction of stars, known as Star Power. There are 2 different sizes of stars. The small star represents the requirements needed for the regular CO power. The bigger star represents the requirements needed to activate the Super CO Power. Each star is worth 9000 funds, basd on the same formula.
Activating a CO Power will decrease the amount of stars equal to the requirement and changes your Star Power meter into POWER. The SUPER will take effect until the start of your next turn. During this phase, you cannot increase your Star Power.
Activating Super CO Power operates the same exact way as CO Power in the previous game. The Star Power meter changes to SUPER. The SUPER will take effect until the start of your next turn. Afterwards, it goes back to 0. Like CO power, activating a Super CO adds a counter to value increase by 20%.
Another big change to the mechanics is that offensive damage increases the bar by double its previous installment, from 25% to 50%.
Missile Silos, introduced in this game, will NOT increase Star Power as they are non-battle damage.
Advance Wars: Dual Strike[]
Some of the mechanics remain the same from the 2 previous games.
However, the values of how the Star Power increases is changed from funds to set values based on units. Each star contains 50 in value. The mechanics of increase remain similar, with battle damage increasing it by 50%, while taking damage increases it by 100%. The values are as follows:
| Value per HP | Units |
|---|---|
| 2 | Infantry, Mech |
| 3 | Black Bomb |
| 4 | APC |
| 5 | Recon, Artillery, Tank, T-Copter, Black Boat |
| 6 | B-Copter, Lander |
| 7 | Missiles, Rockets |
| 8 | Medium Tank, Cruiser |
| 9 | Neotank, Bomber, Fighter, Submarine |
| 10 | Piperunner, Stealth |
| 11 | Megatank, Battleship, Carrier |
During Team Battles, the non-active CO will increase their bar by 50%. When a CO power or Super CO Power is used the other CO can still increase their Star Power as they are not in POWER or SUPER mode.
This game adds another form of CO Power: Tag Break. During team battles, Tag Breaks can only be activated when both COs in the same team has full Star Power. The message will say TAG. Like Super CO Power, being in TAG mode will be gone and set the Star Power to 0 for both COs at the start of their next turn.
Black Bomb exploding, damage from Black Bomb explosions, and cannon damage do NOT count on star increases as they are non-battle damage.
Sasha's CO Power Market Crash is the only CO power that decreases Star Power. It is calculated as 1 star (100 value) reduced per 5000 funds.
The Star Power Skill stacks an additional 10% increase to Star Power.
When the top screen battle is completed, both COs from the winning team will gain equal charge as if they lost the units.
Advance Wars: Days of Ruin[]
This game calls it a CO Gauge. The battle mechanics drastically changed.
You will see a CO Gauge, measured by 12 bars at 6x2. In order to utilize the CO Gauge, a CO must be boarded. The CO Zone also must be used. In order to increase that bar, your units must be around the CO Zone and inflict HP damage either by attack or counter-attack. If the unit that has the CO inside is destroyed, the CO Gauge is reset to 0. Each CO Bar equals 5 HP of value. Unlike the previous 3 games, you do not increase the CO Gauge if you are being attacked. Additionally, each time a CO power is used, there is no value that multiples to make it harder to use the CO Power.
Once the CO Gauge fills halfway to 6 (30 HP), the CO Zone expands 1 square. Once the CO Gauge fills at max 12 (60 HP), the CO Zone expands 1 more square for a total of 2+ and you are able to use your CO Power. If you use your CO Power, your icon flashes and will have all of the CO Zone take effect for the entire map. Until your next turn, the CO Power effect is gone and your CO Gauge goes back to 0.
Tabitha is the only CO that does not increase the CO Gauge during counter-attacks.
Forsythe and Caulder do not have a CO Bar. Additionally, having no CO obviously doesn't give you a CO Bar.