Thanks for the feedback, I'll work on those problems

This was actually quite hard, harder than I expected.
Two big problems, one is fixable, the other one isn't:
1.) The AI either always attacks the first player or the player in the lower right. Anyhow, I was first player and lower right, and the enemy formed a snake marching towards me, it was more or less constant and actually quite hard to stop. As soon as the second player got his act together though, he could just place towers along their marching route and place ranged units on top of them, almost completely slaughtering yellows forces while they happily marched to attack me.

2.) This is fixable: As soon as you destroy the first yellow gate, the ai will be stuck, since the drawbridge also gets destroyed. This makes this a no-brainer since you can build up for however long you like.

We picked Wolf as AI. For some reason he did not build up his economy. No farms, no iron mines, no quarries. He did not wall himself in or anything. Maybe too many objects/units on the map