Confirmed, with before and after pics:
BeefOwnage has 0 cards left and I am about to cast Nightmare on him/her.
(http://i.imgur.com/2V636hW.png)
BeefOwnage shouldn't be drawing any cards yet still loses the game. Funnily, the opponent shows this as the opponent leaving and wins, when in this case (s)he should have lost for decking out.
(http://i.imgur.com/bMdW4HV.png)