A Warrior hero from the Dungeon faction? That's absurd...

A warrior hero from the Dungeon? That's absurd! It's absurd! :) Although, of course, you can try to get lucky and acquire a bunch of skills for a hero with a minimal chance of them appearing, but it's definitely not worth doing that online, especially with a Sorghal. Ignoring the main "spell power" characteristic to strengthen your troops seems rather unserious; I'm almost certain that a warrior hero, buffed in this way, will lose to a battlemage without a chance.