Great Game Idea, unfortunately way too unbalanced. To beat the AI, you simple need to get 2 Pikemen and 15-20 Archers.
Ignore the first enemy wave, then send on two lines your Pikemen (canon fodder) followed by your archers.
The enemy, low on MP (his first wave is gone), will now try to send his units on your two lines, where they are completely destroyed by your archers (the two pikemen are canon fudder). As soon as you've 3-4 Archers after each other on a line, they are so strong, that they may kill even cavallry by the time the cavalry reaches them or at least damage it so hard, overall, the archers are way more cost efficient than any other enemy unit.
I've just won a battle as Moors against Germans, where my 13 units won against 76 enemy units. I've lost 2 cheap moor archers, he lost his whole army!!!
Maximise this tactic by researching all ranged boni and hire an appropriate general (up to 60% more dmg).
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