The new you lose screen let's the entire opponents' army attack before it shows. This however, has caused me to win a game with voodoo dolls, after my opponent had already brought me at 0 hp. And it's not untill another momentumed creature hit me after having 0 hp (I was facing Obliterator with Shak'ars) that I won by having an unmomentumed creature hit my Gravity Forced Doll!
I did not screenshot it since I didn't expect it to happen, but I can only assume this behavior is not intended. If the killing blow is dealt you should lose. I could expect similar thing to happen to decks like Liquid Antimatter as well, basically any deck that makes the opponent hurt itself on it's own turn (which gets finished first).
Edit: a similar situation with Gemini had a different result, the turn ended prematurely, strange... I do not understand what caused it...