Dean: Why are you doing this?
Metatron: Because I can. Because you and your little brother and your fine, feathered friend and all those secrets you’ve got locked away in your bunker can’t stop me. But I am gonna enjoy watching you try. It’s gonna be a hell of a show. I’ll see you around, Castiel. Never forget I gave you a chance.
Metatron: How’s that, um, stolen grace inside you working out?
Cas: It’s fine.
Metatron: No. It’s not. It’s burning out. It’s gonna burn you out.