Deathrattle minions are really good, especially early game so that you can sustain through to mid to late game. Tier 3 deathrattles are especially strong. The main weakness to N'Zoth is that you might not be able to utilize your passive to the fullest but you do have 1 free gold at the start of the game. The other problem is that you don't have a lot of armor compared to other heroes.