Frida's Dilemma - "Duncan" [Campaign 1, Mission 3]

hmm... And how many castles are there in total (not counting the one where Duncan is)? These "elite" creatures, as I call them, are still weak. The Adepts have Blind, which is good, but that bad guy Duncan dispels all my spells. Warrior, how many times did you defeat him? And if not on the first try, what enemy armies did you encounter?

Added after 6 hours 23 minutes
I finished it!
Look at this funny thing in mission 4:
I captured a castle with 17 Zealots, 4 Imps, and 8 Archers.
http://i003.radikal.ru/0802/0d/f0cebdd5daac.jpg