Auto-translated
You say Strike from the Heavens is unknown? When I first launched Heroes V and tried to play the "Falcon's Last Flight" mission, I experienced firsthand WHAT a strike from the heavens is... :( By the way, the AI also has gold troubles sometimes—it can't always manage to buy back all its creatures, which occasionally makes the task significantly easier. And five level 5 heroes also have their own advantages over your single level 30 one—I realized this back in Heroes III... While you are hunting one at one end of the map, a second is capturing a castle in another, and a third in yet another. And then you're running all over the map reclaiming cities. And while you're running around, the first five will level up to about 20, which isn't bad either, and ten new ones at level 5 will appear. And together they'll just swarm your single level 30 hero. In the end, the AI beats you not with quality, but with quantity.