I don't know, I haven't looked into this issue yet. You can also play as different types of characters.

In the Inferno campaign, I chose the most difficult path - Warrior + Blood (no healing, mana for draining is barely enough, troops that want to join need to be killed instead of recruited). Naturally, the difficulty level is the highest. And naturally, without upgraded dynasty weapons (I'm leveling up the Inferno sword that's given in the first mission). I also didn't use a cheat to level up Blood/Tears to 1000 per battle.

But it's still quite playable, not easy, but very interesting.