I barely managed to defeat Kha-Beleth. Based on what I read on the forum, I knew that battles against Duncan and Faydaen awaited me on the other side.
Unfortunately, at the very beginning of the mission, I decided to focus on leveling up Grol, betting on dogs. And that would have been fine, but I never managed to get the Darkness skill on him, and when I reached the mentor, he was already guarded by 4 stacks of angels, each with 400+ units. Without Darkness, with a weak Chaos faction, minimal spells, and growth from only one Castle (the other enemies had successfully burned down the rest), it was impossible to break through.
I later realized that I could have leveled up Nimus in parallel, but it was too late...
At that point, I only had one Castle left, and Vampirism appeared in it, which, in theory, could have been used to defeat the angels if I had gathered enough creatures.
But...
I didn't take any stat-boosting items with my secondary heroes, and therefore, Nimus was too weak in stats to perform well in that battle.
And there was simply no time to run around the map and collect them, when my only city was being besieged more and more often by another knight. And Kha-Beleth's creatures were also growing in numbers, and I had already spent too much time fighting him, and there was simply no way to continue.
What was the result? I had to free the mentor using a cheat... because without Darkness, my Grol simply wouldn't have survived.
I did manage to win the final battles even with my meager army, but because I still didn't complete the map without using a cheat, the aftertaste was bad, and I didn't get the sense of relief after completing such a difficult mission.
Knowing the map, it can be completed. But that's a completely different story, and I simply don't have the strength or desire to spend a lot more time replaying it without using a cheat.
As was written earlier in this thread, the Master is a great master in creating maps, but he is also a great master of disappointment. His maps cannot be completed on the first try (even on the easiest difficulty). They need to be worked on for a long time, constantly making mistakes and starting over...
This is not relaxing. It's just constant stress. I haven't encountered more difficult maps yet.
I don't even know if it's worth starting a war against the Orcs, if I already know that I'll have to replay.