Dragon Spell by virtualpersonal and brimstonegold (LJ). Rated NC-17, Sam/Dean, 112k. Summary: Crossover with Anne McCaffrey 's Dragonriders of Pern. Snooping around in his father's storage locker, Sam touches something he shouldn't and gets sucked into a world where dragonriders must protect their world from a continuous threat of threadfall. Dean follows and finds Sam has lost his memories. Until they get out of this mess, they have to ‘make like the natives. '
virtualpersonal.livejournal.com/206751.html
my thoughts: This story was my gateway fic to dragon AUs and it's been ah👏ma👏zing👏 reading and exploring this one and all the others! While it 's a crossover with Anne McCaffrey 's Pern universe, I had no idea and rolled with it anyway, so you definitely don 't need to have read the McCaffrey 's series to understand this story (but it 's a great in that it gives you the gist of what other Pern x SPN fics incorporate in their crossovers as well). Love the amnesia trope deftly used here to kinda excuse/explain how the wincest unfolds, haha. This fic was featured in my wincest noncon reclist too (there 's an instinct-to-do-it-overwhelms-rational-thought trope to things which I consider noncon-y)

A Fire Ever Burning by BewareTheIdes15 (AO3). Rated NC-17, Sam/Dean, 16k words. Summary: Crossover with Anne McCaffrey 's Dragonriders of Pern. Sam and Dean have always been oddities among the dragonriders; the youngest man to Impress a Bronze dragon in a hundred years and a boy who turned his back on the riders to become a dragon healer instead. But when fate steps in and chooses a far different path for Sam, the brothers and all the Weyrs of Pern will have to come to terms with much greater changes in their traditions.
ao3.org/works/545249
my thoughts: I adored the scene where ‘fate steps in and chooses a far different path for Sam, ' holy shit. Such an exciting, magical scene. The rest of the story follows form. Warning there 's some rape scenes in this if I recall correctly.

Somewhere Between Hell and the Sky by cleflink (AO3). Rated PG-13, Sam/Dean, 17k words. Summary: Ever since their mom was killed in a dragon attack on the city of Lawrence, Sam and Dean have earned their living as dragon hunters. It's a decent enough gig, until Sam fails to die after being doused with dragon fire and promptly starts acting strangely even by his standards. And Dean would like to help, but between the dragons apparently being very interested in Sam and Sam apparently being very not interested in Dean's help, he's not sure which problem to tackle first.
ao3.org/works/3223658
my thoughts: ahhhh I need to reread this to remember it & detail what I liked about it but it was in my AO3 bookmarks, meaning I loved it enough to suggest to myself it 's worth a reread.

Borne of the Earth by hybridshade (shimyaku) (AO3). Rated NC-17, Wincest, 14k words. Summary: Dean is born and raised with the pressure of becoming the greatest of Riders always hanging over him. But when the big day comes and his destined Pledged Dragon doesn't show, Sam proves he will go to the ends of the Earth to make it right again, if only for the sake of his brother.
ao3.org/works/2244471
my thoughts: Solid story, and so much anticipation built for Sam to reach a certain revelation that everybody could see coming. So good!