User blog comment:CROWMETA13/End of season 11/@comment-95.115.134.145-20151123160324/@comment-26847591-20151219113738

I think the Darkness might take Dean with him and Dean lands in the Empty. Then in the first episode of season 12 God has to find a way to free him but destroys bit of it and frees some creatures that have been dead for billions of years or have just started to exist in that particular moment and that's what they have to fight in season 12.