Advance Wars: Dual Strike/Duo Falls

Duo Falls is another fairly balanced well-rounded map that introduces airports to both sides.
 * Enemy CO: Max (specialized in direct combat). Max can be quite formidable if not taken seriously.
 * Map dimensions: ??x??.

This guide is focused on quickly rushing the central region, then slowly advancing toward Max's HQ with heavy air support.

Setup
A good CO choice here is Eagle, the daring pilot from Green Earth. Given that you have airports to begin with, in addition to one easily reachable one at the central region, Eagle's air units will quite useful. Eagle's CO power and SCOP are incredibly useful as well, both of which allow non-infantry units to attack again.

If you playing with skills enabled, the following skill set is recommended for Eagle:
 * Star Power (power meter fills up quicker)
 * Brawler (direct attack +8%)
 * Slam Shield (direct defense +8%)
 * Fire Sale (production cost -8%)

The reasons behind this setup is to maximize direct offense/defense to counter Max, while reducing the cost of the expensive air units.

Strategy

 * Objectives
 * 1) Capture the central factory and airport early on.
 * 2) Slowly advance up the central region with tanks, midtanks, and choppers for air support.
 * 3) Timing your SCOP to quickly close off the central region entirely.
 * 4) Cleanup with tanks and bombers if you can afford them.

First turn, build infantry at every factory. Second turn, build a transport chopper with one battle chopper. Third turn, another transport chopper + tank at the rightmost factory. The main goals are to quickly bring your infantry within capturing range of the cities at the central region. After several turns, you should have most of these cities captured, in addition to the vacant factory at the central region.

By now, Max should start be packing at least 2 anti-airs at the sight of your choppers. At your right most factory, make sure you build 1-2 tanks early on, in addition to 1 anti-air. Afterwards, start building an artillery/rocket. Key point is for your ground units to target enemy anti-airs so that your choppers can efficiently attack Max's tanks/infantry/choppers. Depending on the situation, Max may or may not have a fighter jet ready after a number of turns. If he happens to have one, withdraw your choppers and lure him over into range of your anti-air with a transport chopper. Because we are facing Max here, his indirect units should not be a problem, so rushing ahead with your tanks and choppers should work fairly well.

By midgame, you should be in good standing for a SCOP. Use it wisely to clear out the middle region entirely, and place a unit on Max's northernmost factory. At this point, once you have the bridge secure, set up a defensive position with your rockets/artillery, and start saving some funds for bombers. You probably can build 2 or so, before rushing. From there on, its a simple matter of letting your tanks take out anti-airs, and choppers/bombers taking out another units.

Summary
Estimated time of completion should be around 11-13 days with skills, and near similar time without. An S-rank should be achieved easily if the objectives are well.