Dean was tied down in the basement to a chair that Sam placed him in called the devils trap. Dean had the mark of Cain.. not a fun thing.

He’s been turned into a bloodthirsty killer, and he loves to be the sociopath that he now projects himself to be.

He sees the heavy metal door opening.

“Hmm well, well, look who decided to finally come around, I hope Sam warned ya.” Deans eyes flash black as he chuckles.