I have Trolls, Khador, Farrow, Ret, and now I want Cryx. I see almost every McThrall list has the Necrosurgeon and keep reading about how amazing the model is. I understand that it brings Mc's back to life, but I think I'm missing how it's so good. The thralls are fairly terrible in terms of DEF and ARM so most of them should be dying every turn, maybe the entire unit against ranged attackers. At best that's 3 returned thralls overall, how is that good?
Like I said, I know I've gotta be missing an important aspect, but I'm having trouble discerning what it is.