mrshch
Auto-translated
Regarding the battles: I'll briefly describe it; it's not that complicated.
However, I'm stuck with the birds. If a single unit takes out the retaliator, the Magma Golems attack last, and after them, there's no one to take the place of the defeated bird stack. Therefore, other birds move in and attack the main stack of Spearman.
And if you don't attack with Spearman, the stack isn't completely defeated by the Demons and Magma Golems alone.
Added after 28 minutes
Ha! I just defeated the birds, but with a slightly different strategy. First, I attacked the fifth unit, and the Blessed Magma Golems took out the retaliator. It can be killed without using Spearman, and they remain protected. Then, if the sixth unit kills a single unit (which is quite likely), the last single unit takes out the retaliator, and the birds are finished.
Added after 23 minutes
I arranged them like this: Magma Golems on the fourth cell from the top, Spearman below them, and Demons below them. Single units cover everyone; there's only a gap at the bottom for the Demons, but the birds never go there. Then, no matter how the birds attack, the fifth unit is always hit by both the Demons and the Magma Golems. On the third turn, the birds might attack the Demons or Magma Golems, but they never touched them in my case. Then, everyone attacks them again.
The requirements for luck turned out to be small:
--no anti-morale in the first and third rounds
--no anti-morale for the Demons in the second round
--morale for the birds
--no lightning on the first retaliator
That's all!
Added after 25 minutes
I got carried away: sometimes the birds attack the Demons, no matter how many single units you expose.
And very rarely, but sometimes, the sixth unit survives in the third round.
But still, the battle is more than possible.