Aemon Targaryen (Dragonknight)

Aemon Targaryen is an unseen character in Game of Thrones. He is long dead by the time of the series. He was a Prince of the Targaryen dynasty.

Background
Prince Aemon was called "the Dragonknight" on account of his heritage. He was raised to the Kingsguard at age 17 and eventually became Lord Commander. According to tradition, he was once saved from a snakepit by his nephew Baelor I Targaryen, whom the snakes refused to bite. He fought and barely defeated Lord Cregan Stark. He also wielded Dark Sister, the Valyrian steel sword of Visenya Targaryen.

Season 4
Aemon's life is recorded in the Book of Brothers.