I wonder how you will manage to win the battle.
I managed to win with 34 bears.
https://yadi.sk/d/UTahdFLT3RFTUx
https://yadi.sk/d/S0RnpINM3RFTWs
New here? I'm Roha — want a quick tour?
It took me two tries, but I managed to do it this way: see the screenshot.
Maybe it's possible to do it perfectly, without any losses, but this was a quick solution.
In short, the monsters will win the battle. I cast Prayer and Counterspell on my troops, then resurrected them. Finally, I blinded the remaining archmages, calmly resurrected everyone I had enough mana for, and finished off the archmages.
Now I'll try to fight more slowly; it will probably be better.
Cleared it on the first try without any losses, and I still had 49 mana left (which I wasted on an unnecessary clone of the behemoths, among other things) :D