Well it's been done before and it was a great combo back in the day. It just takes too long to get the Ravenwraiths to high dmg, and that's generously assuming you draw them early.
Yeah, ravenwraith and czar are both very high-cost champs (86 each), and both are fairly squishy. Shield of darkness on ravenwraith with vaporize helps a bit, but you generally are playing on the back-foot until you can get a restless souls proc or a few revenant casts to start the vengeful engine. it's hit or miss. then again im a pretty mediocre player, so maybe you will have more luck with it!
I'm surprised there aren't any Lich Magistrates in any of these decks. He seems like an obvious choice. I've been considering trying him out, but I'm having too much fun with Skeletons and Skeezick.
He is in my deck and discussed above, I just still call him Czar of the Void, which is a way more badass name and what he was originally called and forever shall be in my heart.
Oh, now I get it, durr. I just kinda skimmed over that since I didn't know what was going on. I stand corrected!
How come I don't really see a lot of Umbral Wolf in most Spirit bgs? Is he bad, unnecessary, or just requires a different build?
Umbral Wulf is a great champ, but... There are only so many slots in a spirit BG and the other champs fill the holes in the BG better. ie, Ethereal Soldier.