Maester Luwin gets the shaft when Ramsay Snow (ne Bolton) attacks Winterfell and an Ironborn captain just knocks him to the ground and shafts him for no apparent reason. He was trying to counsel Theon. Maybe that was his punishment. He died later in the godwood, when Osha gave him the gift of mercy.
Tyrion: Let me give you some advice bastard. Never forget what you are. The rest of the world will not. Wear it like armor, and it can never be used to hurt you. Jon: What the hell do you know about being a bastard? Tyrion: All dwarfs are bastards in their father's eyes.