patch. While in theory, emerald dream could be cool. However, the major threat there was solved. While there is the void flower thing there, I don't think there is enough there to make an expansion around. Maybe the end of DF could bring in the emerald dream as something like zereth mortis, timeless isle, etc, along with a raid. But then again, we've already been there. So... without the nightmare being a thing, I can hardly see it even being a patch unless blizz uses the plot device of the flower. Who knows. But certainly, without doubt, a patch.