I've said it before, but the Alt John and Mary armbar scene is something I know deep down that Dean and Cas did too—especially after the first time Cas got cut off from Heaven.
Aside// I'm laughing at them SO much, because when John strains his arm, Mary goes all sparkly-eyed WHAT IS THIS FEELING OMG
//
Anyway, over in my season 5 headcanon-land, Dean keeps taunting and lecturing Cas about how in real fights, anything goes, and you have to fight dirty—and Cas is just rolling his eyes, because if anyone knows that, it's Cas.
Anyway, TL;DR: Dean, Mr. Junior Wrestling Champion himself, does get Cas in the armbar.
And
Cas ends up biting Dean's leg.













