90. "What Is and What Should Never Be" (Season 2, Episode 20)
While hunting a djin, Sam and Dean experience an alternate reality where Dean has his act together.
89. "Soul Survivor" (Season 10, Episode 3)
Sam and Castiel cure a demonized Dean. Castiel has help from Crowley, who offers some stolen grace.
88. "Girls, Girls, Girls" (Season 10, Episode 7)
Crowley's mother, a witch named Rowena, is back, and raising a new coven. Cole catches up with Dean and finds him cured. Just as the Crowley character injected life into the series, so does Rowena.
87. "Book of the Damned" (Season 10, Episode 18)
Charlie Bradbury (Felicia Day) returns for one of her better episodes. She's found the Book of the Dead, which might hold the answer to removing the Mark of Cain from Dean. Don't get me wrong: she still says annoying things, like "Let's get our Alan Turing on and decrypt this bitch," but the story's strong. Meanwhile, Castiel reclaims his grace after a road trip with Metatron, who procures the demon tablet.
86. "Dark Dynasty" (Season 10, Episode 21)
We find that the Styne family, who are highly interested in the Book of the Dead, are actually the mythical Frankenstein family. That sounds stupid, but it's a solid episode, even though Charlie is still an awful, pandering character who says things like, "I'm not a witch. I'm a nerd, and I've studied at all the great centers of nerdom." Well, I guess if I were fortunate enough to be a writer on one of the greatest shows of all time, exploring issues of life and death, heaven and hell, and fate and free will, I might also throw in some crap like that for ratings and to keep my job going. Or maybe they just wanted the audience to feel better about her being murdered by the Frankenstein brothers at the end of the episode. It's hard to say.