Gold, Frankincense and Myrrh.
I come bearing a recommendation.
This story was written ages ago for the apocabigbang and has been sitting in my "need to read" folder for just as long. I finally got around to it tonight and all I can say is WOW.
Beautiful and somewhat grotesque (it is the apocalypse) and vivid, the reveals are all just astounding and it's incredible how tabaqui weaved the season 4 (and 5) mytharcs into this new world. It feels so real, so natural, like this is exactly how it should happen from here on out and the events unfold so fluidly it feels like the reading time just passes you by. It's mostly gen, for those that do not read slash, but there is a bed sharing moment and later a small kiss moment between Sam and Dean that is more brotherly than anything else.
Comes to Dust - Tabaqui.
There isn't a masterpost, so the link takes you to the first of three parts.