Karl Tanner is a recurring character in the third and fourth seasons. He is played by guest star Burn Gorman and debuts in "Walk of Punishment." He was a brother of the Night's Watch who had gone north of the Wall on Lord Commander Jeor Mormont's Great Ranging. Karl led a mutiny at Craster's Keep in which he and his fellow mutineers ―mainly ex-criminals― killed Craster and Mormont, but he and his comrades were later tracked down and killed by a party of the Night's Watch led by Jon Snow.