Synergizes with corpse taker giving it 2 out of 4 keywords, deathrattle is amazing and can be done pretty well with cards like umbra and spirit caller. Heck may even run the Tirtollan to get more of these... if only it wasnt so slow
This is exceptional against midrange decks and has great N'Zoth synergy, but against aggro and control....eeehhhhh. Not so great there. The deathrattle will probably be impactful enough against control to be fine, but it's random so if they have small minions to play then they can reduce their chances of it killing off a key minion.
I'll say "Very Good" for now. But 9 mana is very expensive. If you play it against aggro it's GG, but making it to turn 9 can be a challenge.
There are so many ways to cheat this out and to get more copies of it and the huge value it provides is just insane. I also love how well designed it is. It doesn't have a lot of stats, but its very flexible against both board flooding (due to lifesteal) and big minions (due to its deathrattle) and with Awaken the Makers you can heal even more (especially given how much more Deathrattle synergy there is, it should be trivial to complete that quest now with good Deahtrattle minions being run).