Originally Posted by kepp
My thought on that has to do with what Crowley said to Dean when he died. He mentioned that Cain died, but the first blade wouldn't let go of him. And then when Crowley placed the blade in Dean's hands, he came to as a demon. I'm guessing that the first blade has the "transforming" power. So if I stick to my theory, Cain is dead.
That would make sense. Human Cain was turned to a demon, blade would not let him die. Now Dean has all of those powers and gifts. He is basically on par with Crowley.
To balance this Sam will need powers which hopefully leads them to leading both sides and then a quality spin off.