Long before Sunday night's epic episode of Game of Thrones confirmed the popular theory, fans of the HBO series have been waiting to see if one of Dany's dragons would become an ice dragon. Viewers witnessed the heartbreaking transformation in the final shot of "Beyond the Wall" when the Night King turned Viserion into a blue-eyed beast, but the scene left fans wondering: are ice dragons real in the Game of Thrones books? The myth certainly loomed large in George R.R. Martin's books.
Throughout Martin's five published A Song of Ice and Fire novels, several characters have made mention of terrifying beasts called ice dragons, but little is revealed about them, including whether or not ice dragons are actually real or just another one of Nan's scary stories. The first mention of the creature is in A Clash of Kings when Osha, Bran's wildling companion, explains how she navigates the north so well: by following the blue eye of the Ice Dragon, a constellation that makes several more appearances throughout the novels.
But talk about real ice dragons doesn't come up until the third book, A Storm of Swords, when Jon compares walking through a tunnel in the wall with "walking down the gullet of an ice dragon." The King of the North makes a few other references to ice dragons in A Dance With Dragons when describing — yep, you guessed it — the cold norther weather and life on the Wall.
Though these mythical beasts are referenced several times throughout the series (you can see the quotes here) and even get an entry in Martin's A World of Ice and Fire reference book, where they are described as "colossal beasts, many times larger than the dragons of Valyria, are said to be made of living ice, with eyes of pale blue crystal and vast translucent wings through which the moon and stars can be glimpsed as they wheel across the sky," there is no actual proof that these beasts ever existed.
So, are ice dragons real in the world of A Song of Ice and Fire, or just a story meant to scare children? Is there no proof of their existence because they melt when they're slain, or because they never existed at all? Is Viserion an actual ice dragon, or did the Night King just created another wight to fight for the Army of the Dead? We will just have to watch next week's Game of Thrones season 7 finale to (hopefully) find out, because the books don't offer a definitive answer... yet.