I can't roll well. In fact, I can't roll higher than seven on two dice. Then I picked up Calandra, she of rerolls. With an abysmal track record of dice fails, this caster is essential. With her around my Mountain King can actually hit something, charging dire trolls deal damage and some of my battle plans actually work (sometimes).
Calandra is also a detail-packed model to paint. When I saw the Mountain King's crater I knew it had to be her base, I think it worked out well.