Twilight of Darkness

I would say that she should have won without a doubt. The trick here isn't so much in the attack on the zombies, but in the fact that the imps attacked. If they steal mana on their turn, winning becomes almost impossible. The Necromancer can fight back using the Necromancer's sign, but the other races have no options. (Barbarians will most likely be severely damaged in the first attack). To prevent the imps from stealing mana, you have to sacrifice your own unit (Death Messengers). This is a very bad option when the imps can't attack anyone due to the map's features. Then they steal mana every turn, and they move often. I have a suggestion: reconsider the concept of the final battle.
I'll try to find the save file; I don't think I lost everything.