When I fought the final boss, I was doing it on Normal difficulty, with a party of four:
Shadowblade (Witchcraft/Scoundrel)
Wizard (Fire/Earth/...some Water)
Jahan (Water/Air/Witchcraft)
Madora (Fighter)
I didn't have any crafted weapons, my best dagger was the Snakebite. I didn't use any CC on the boss at all.
I spent the first part of the fight healing Astarte-the-Tissue-Paper-Goddess, and trying to kill all the minions. As soon as the boss summoned in his first wave of reinforcements, I realized that I had to spend some time focusing on him. My Shadowblade went behind it.
The boss completely ignored all my backstabs as long as I was sneaking at the end of my turn. Eventually, after I whittled down the summons enough, Madora was able to join the fight.
I didn't die, the fight wasn't particularly hard, I just didn't like the "escort mission" part of it. The Void Dragon focused on her too much and ignored the rest of the party.
