Ice and Fire

I don't know how to kill Hangwula.

In a week, while he was making his way to the castle, he increased his army by 25% and constantly uses Rune Recall in battle, which gives him infinite mana. He also uses Earth Shock, Meteor Strike, and Fireball. He doesn't use Darkness, only Chaos. This is more than justified by his magic power and infinite mana.

Heh. I posted recordings of battles with him. He always used Blind on me, plus other minor spells. In principle, I managed to drain his mana with my spells. I had a lot of them.

Would Subdue help? The last artifact of the Dwarves is not far from Thor Hall. If you try, you can get it, if the hero has the remaining 3. Or, if you have a save before capturing the garrison, try to build up an army and capture everything you need.