The most challenging campaign.

Honestly, I don't understand where the hero Isabelle came from in the demon campaign... The third mission is indeed difficult... because this jerk, Gilraen, even with a smaller army, still defeats you due to the lack of morale in your troops and due to sheer luck.
I passed it like this: I gathered a large army and captured all his cities, snatching the last one right under his nose. He was within walking distance of the city, but he was afraid to come to me, so he ran to another of my cities. I grabbed the reinforcements and chased after him. As soon as his turn came, he saw that the city was free and ran to it, but he didn't have enough moves, while I had plenty)). I entered the city again, and it all started over... like that for 7 days, and then he lost like a broke elf.
P.S. The second time I replayed, I finally killed him)).