Here I go over tips on beating this coop.

When the game starts, immediately move your commanders to any platform to start spawning armies right away. Focus on countering the path enemy comes.

Assign your two howies to hotkey 1 and 2. Use them right away to destroy enemy defenses you can reach, and defend your base. You'll have to continue to use them for at least the first 10 minutes until your armies are built it.

Focus on middle if you can, while it is the hardest path, it has a reward if you capture the enemy capture zone that has multiple red circles.

Watch enemy movement, and change your paths accordingly. Don't let enemies get into your base too much.

After 5 minutes, tank platforms open up, and 5 minutes after that, all platforms open. Switch your commanders to tank platforms, and simply try to choose lanes enemy is not in - while at the same time watch your base doesnt get destroyed.

WATCH YOUR POPULATION. If it hits or goes over 200, enemy will bring in 2 Tiger Tanks and bombers. However, once your population goes back under 200, they stop.