I noticed this during the week while playing a match with daxos, the returned against an opponent ashiok, nightmare muse deck.
Well, enemy of enlightenment gets (temporarily) -X/-X before each combat phase, while is X is the amount of opponent handcards.. being a 6/6 creature would actually mean, that it’s going to die when the opponent’s hand is full at the beginning of combat.
In fact, it gets -6/-6 but isn’t dying at all in such a scenario.. instead it stays on the board as a 0/0 creature until the end of turn, when the negative buff is removed and it gets back it’s original P/T stats..