We have reviewed Together, They Fight Crime where Cas has very special powers and you may want to check out this ask about crossover with Avengers.
Here are some unofficial reccs with superheroes.
Holding Hands with God [NC-17, 7269 word count ] and sequel A Graying Tower, Alone on the Sea [NC-17, 13,005 word count]
Dean is a superhero with issues, Castiel is a mild-mannered reporter trying to date him.
For Truth, Justice and Led Zeppelin [M, 44,500 word count]
Being a masked vigilante is difficult enough when you’ve got petty thieves, drug dealers and a day job as a photojournalist to deal with (not to mention trying to keep your little brother alive so his wife doesn’t skin you). The last thing Dean Winchester needs is for his city to become the battlefield for an apocalyptic showdown between the forces of Heaven and Hell. But, like it or not, he’s being (literally) swept off his feet by an angel and thrown into the middle of a war he’s not ready for. Featuring superheroes, leather pants, secret identities, and Dean’s weird new coworker - Jimmy - who never seems to write any articles and won’t stop staring at him.
Head For The Exits [NC-17, 24,762 word count] (our review)
Dean’s life in the Edge City PD is going swimmingly: There’s a masked vigilante prowling his rooftops and nursing a crush on him; a serial murderer who’s too damn smart for his own good; his partner is so new she still smells like Academy polish, and he can’t quite work up the nerve to ask out the coffee guy across the road.
Kryptonite in Shades of Blue and Green [NC-17, 12,781 word count]
Dean is the only member of the Winchester family without super-powers and has lived with the threat of being used against him all his life. When Dark Angel finally makes threat reality, Dean ends up trapping them together for two months. A lot can happen in two months. Written for this prompt on the spnkink_meme. WARNING: While I did everything in the story I could to make it clear this does not warrant the archives’ rape/noncon warning, Dean is Cas’ prisoner so consent, no matter how willingly portrayed, does have a unavoidable dubcon vibe. Since neither ‘dubcon’ nor ‘bodice ripper’ are among the site’s warnings I opted for the ‘Choose Not to Use Archive Warnings.’
Alchemy [M, 38,000 word count] AO3 link (our review)
Castiel Novak’s life is average until the day he wakes up with superpowers. Soon after he meets Dean Winchester, an investigative reporter with a knack for getting himself into trouble.
Renegade [T, 9,300 word count]
Officially, Castiel is a deeply committed, borderline workaholic PA. In reality, he’s little more than a glorified babysitter to a spoiled superhero.
See the Light [NC-17, 40,278 word count] (Cas has special powers) the author has taken this story down and doesn’t want it publicly shared
It was the middle of the night when Castiel got a phone call from a man he barely knew in high school. Dean Winchester’s younger brother was missing, he thought Sam joined up with the cult that set up camp just outside Lawrence and he heard Castiel was just the right man to get information from to use to tear them apart. Castiel was forced to confront parts of his past he left behind, but what should have been just a simple missing person’s case quickly turned much more dangerous than either Castiel or Dean ever bargained for. They discovered just how dark and twisted the Seven Thunders were. Only through quick thinking, and tapping into power Castiel had tried for years to keep a cap on, could they hope to make it out of the cult’s clutches alive
Despicable Misha [NC-17, 52,000 word count] cockles crossover with movie Despicable Me
In a world where super-villains have to compete against each other each day to gain the respect of the Evil League of Evil and the support of the Bank of Evil, Mischievous Misha struggles with both, plus a distinctive lack of new ideas for heists. He’s been in the business for quite some time, and though his minions and his best friend Jared keep him busy just fine, it’s only when Jensen moves into the house next to Misha’s that he becomes aware there’s something more to life than being evil. What he doesn’t know is that Jensen is a villain like himself, just younger and an up and coming one, and only moved here to put Misha out of the way.
Edit: found some more!
Turning a Blind Eye [PG-13, N/A, longish]
swing_set13 who wanted a superhero story with Cas as a mild mannered reporter working with Dean only to find out they are both superheroes who don’t really get a long until they do.
Echoes and silence, patience and grace [T, 8,290 word count]
Being a superhero is awesome. Sure, the press is always in his shit and he really, actually hates that, but he’s Dean Winchester. The press hasn’t given him a break since the mid 90’s. (Supernatural as the Avengers!)
Look, Up In The Sky [PG-13, 9,993 word count]
In this exciting issue we cast our eyes on the mysterious metropolis of Lawrence City, and its two valiant protectors, strangers from another world striving to save the helpless citizens from the most dire threats imaginable! As threats mount from without and within, can these two unlikely partners overcome their differences in time to defeat the deadliest enemy they’ve ever faced? Or in a world where smoke can dress itself in human skin, can this tale that can only end in tragedy? Face Front, True Believers, and find out!
Castiel & His League of Super-Powered Associates [R, 19,260 word count]
A crossover with DC Comics. Jimmy Novak, CEO of Novak Industries, is Castiel the Avenging Angel by night, bringing justice to the streets of Gotham. When Integriman the superhero of Metropolis asks him to protect his brother Dean, Castiel finds himself developing feelings he usually tries to avoid. But as Dean becomes the pawn in dark games played by the villainous Alastair and Crowley, Castiel struggles to decide where duty ends and obsession begins.
If our followers know of any other, please drop them in our ask box!