quigonejinn

I'm not known for my badass tastes in fic, so this is the best I can do.

Old Country, by astolat. SPN crossover; Sam/Dean. (Caveat: The sex, IMO, borders on nonconsensual, but it's skippable, and the rest of the story is too great to miss.)

Transfigurations, by resonant8. Harry/Draco. A lot of cool magical theory.

On the Subject of Evil Plans and the Overtaking of the World, by lalejandra. Hermione/Draco. May be more snarky than badass?

Close Enough, by helenish. Harry/Ron. May be more angsty than badass?

And since I'm here, I think my story This River Runs Red (SPN crossover, various pairings) is pretty badass, but it's preceded by several decidedly unbadass prequels.