Almandine Shards

Once, 40 Seraphs lined up in front of the castle! They wiped out 90% of the already meager army, and it was impossible to advance further.

I understand. When I was testing them, I used "Raise Dead," Adepts (they have "Blind" in their spellbook – a skill from "Heroes of Might and Magic V: Hammers of Fate"), and single units. But you can also use "Battle to the Last," "Storm Wind," and "Lord of Cold." The losses in this battle were 25-35% of the army. After the battle, 100 Zealots join you from the map, which is enough to find reinforcements in the forest.