He is probably best known for his role on Psych, and he has spoken positively about his involvement in Deadwood. He has also appeared in Lucifer, Supernatural, Galavant, and voiced Star Wars characters. He has good stage presence, and I think he will be able to pull off our less taciturn and more charismatic dwarven king. I like his voice - I think he can be sympathetic and likable even in unsavory roles, so I think he'd be great as Azaghal. I could picture him attacking a dragon.
He appears at the 1:22 mark in this video, which I include as he's better known for his comedic roles.