This is an underrated Grand Strategy/4x game ever made. When I first played it, I thought: what a weird game, it sucks. And stopped playing. I even deleted it from my Steam library. But a little later, I gave it a second chance. I don't remember why. Then I realized its depth, and it's my favorite strategy game to date. Still learning things about it.
I actually think it's even better than HOMM III.