"Anything." Dean answered honestly. "He specializes in pain, in making people feel as much pain possible. It's like...like his thing. I think he gets off on making you hurt in ways you didn't even know were possible. He slices and cuts and hurts you until you go from being a person to something less than a person, and then from that to a demon. You are gonna have to be prepared for anything, because he doesn't have anything that he wouldn't stoop to."
And that was the easy part to admit.
"I don't know what, if anything, works against him. Mom tried an exorcism on him and that didn't work, he's said that what Sam can do, and Ruby's knife don't work against him. The only thing I can think of is the Colt, because it's supposed to kill anything, but I don't even know if that will do the trick."