Ice and Fire

Well, I'm trying!
I kill all the mobs without any losses. I cleared everything around the castle between the 1st (which appears almost at the beginning of the game) and the 2nd caravans – I didn't kill only the guards of the Gnomish Artifact. Between the 2nd and 3rd caravans, I cleared the entire territory up to the 2nd castle and defeated the hero. It seems Hangvul didn't manage to gather enough troops yet.
Between the 3rd and 4th caravans, I'm thinking of capturing the 2nd castle and clearing out everything that's undesirable there. Or maybe I'll even try to take the 3rd castle. We'll see how it goes. I just defeated a combined army from the castles, i.e., the computer without troops, but it's building up quickly – slowing it down is not a good option.