5. The Night's King
The Night's King is a legendary figure who was the 13th Lord Commander of the Night's Watch. The story goes that he was ranging beyond the Wall when he came across a woman with ice cold skin, which was also as "white as the moon" and her eyes were "like blue stars." He gave her his seed and his soul, and took her back to the Wall, declaring himself King and her his Queen. They ruled for 13 years, and committed all manner of atrocities in that time. Later, it was discovered that he had been making sacrifices to the Others. In the books he remains very much just a figure of myth, with George R.R. Martin comparing him to other legendary figures Bran the Builder and Lann the Clever,
saying he was "no more likely to have survived to the present day than they have." In the show, however, he is a real figure in the present day storyline, having had a total stare-down with Jon Snow at the end of Hardhome. He's clearly the leader of the White Walkers, and is going to be the one with the biggest part to play going forwards. Night's King vs Jon Snow. Make it happen.