HAHAHAHAHAHAHAHAHAHAHAHAHAHA
JARED, YOUR FACE, SIR. HOW.
Okay, so the obvious first step would be for Sam to cure Dean, but would that count as Sam's Third Trial since he never finished it the first time? So that could be the reason they don't immediately "fix" Dean. That, and I'm pretty sure Dean will hide from Sam rather than admit he's become a demon, so I bet the brothers will be separated for a few episodes, if not the whole first half of the season (probably not the whole half; viewers would revolt).
S10/the series could end with Sam sacrificing himself, DYING, closing Hell, and curing Dean.
If that happens, YOU HEARD IT HERE FIRST. Probably. Maybe.
THAT HAD BETTER NOT HAPPEN. I could kind of see them doing it, though, because of the poetic heartbreak of brother-sacricificing-himself-to-restore-brother's-humanity + closing Hell as the series' swan song (b/c surely we are not going past S10, y/y?). :/ OTOH, we have pretty well established that Sam can live without Dean (although the "I lied"- HA! LOVED IT), but Dean can't live without Sam, so if only one brother made it out of the series alive, I don't think it would be Dean? Obviously that would be more ~traumatic for the characters, but LBR, in a Sam-is-gone-for-good scenario, how long do we really think it would take for Dean to kill himself? So it would not be plausible for Sam to sacrifice himself and to expect Dean to continue living without Sam. Unless they ever actually followed through with Destiel and Cas was Dean's reason to keep living, like Lisa and Ben were. The Destiel was certainly strong with this episode. And if Cas becomes the steward of Heaven and Dean is King of Hell they would make a helluva power couple. I dunno. I can't see Jensen agreeing to it, but if they're not going with Destiel, the writers took the queerbaiting to a whole new level in the past two eps. Anyway. NO KILLING SAM.
Dear Not-Metatron,
Pls for Dean to not actually be evil.
Pls for Sam to NOT DIE.
Pls for Dean kill Crowley and become King of Hell.
Pls for Dean and Bela finally have angry!sex.
Pls for her to not die or be evil. I would rather never see her again than for her to be evil and killed.
Emphasis on PLS FOR SAM TO NOT DIE AND FOR DEAN TO NOT ACTUALLY BE EVIL, KTHANXBAI.
Sincerely,
Alexandra