Tactics for playing as the Dwarves.

Hello! I usually choose Erling as my main hero because he has spellcasting skills, and gnomes don't often get that. I level him up to become a lucky spellcaster and choose the "Battle to the Last" skill, meaning I focus on defense. I learn Armageddon and Pyrokinesis, and I attack the enemy a few times, using single dragons and Armageddon. I'd like to hear all the pros and cons of this tactic. Also, the Rune of Invisibility is very helpful.