D. Mike Ehrmantraut
A cop who got fired for being a total mess. Now works for Gus Fring and gets paid to keep people scared.
"Mike? I didn't know you were still alive. I thought you were dead in a ditch."
"He's the guy who makes sure your problems don't get any bigger than your face."
"Mike doesn't talk much. But when he does, you better listen, or you'll end up in a hole."