George R. R. Martin has revealed how big Daenerys Targaryen' dragons could be when they're fully grown. The author has posted an image showing Aegon the Conqueror on the back of his dragon, Balerion the Black Dread.
Martin has told Entertainment Wise that the picture represents his vision for what a fully grown dragon will look like. The image comes along with an excerpt from his upcoming companion book, "The World of Ice and Fire: The Untold History of Westeros and the World of Game of Thrones."
The excerpt focuses on Aegon I Targaryen, the founder of the once ruling Targaryen dynasty of Westeros. It also provides historical information on House Targaryen and details on how Aegon conquered the Seven Kingdoms to be the one true king of a divided realm.
Martin announced the completion of this "worldbook" in March. The book, which has been many years in the making, is tentatively set for release in October.