Night's King

The Night's King is a figure in the Game of Thrones mythos and potentially the true main antagonist of the series as a whole. He was the thirteenth commander of the Night's watch, who sided with the Others, and is the apparent mastermind behind their coming invasion. He is the secondary antagonist of Season 5.

The religion of R'hllor claims that he and the Walkers are servants of an evil god of ice, archenemy of the Lord of Light, known as the Great Other. Red Priests claim that only Azor Ahai reborn can stop them and the Long Night that Never Ends.