yea without all the deathrattles, not sure if it'll be that viable but seems like a pretty sick card in theory especially in the wild. worst case you have an expensive 5/5 but in most cases at worst you get a 6/6 with 1 unit on board.
Very interesting priest legendary. Good synergy with museum curator I suppose. Just seems like a good card that can be added to a variety of decks rather than something to build around.
Kind of disappointed that this wasn't neutral because it would be an awesome addition to raptor rogue.
Volazj is good if you get it with pretty much any deathrattle, plus Cleric is a possibility. Getting two vanilla 1/1's is fine'ish value. I don't think there'a any Velen/Malygos OTK stuff there. There's pretty decent Museum Curator synergy, although I have no idea how good MC is with Standard card pool.
My only hesitation is that it might be a win more card.