Balerion and Drogon are arguably the two most famous dragons in the Game of Thrones universe. Aegon I Targaryen brought Balerion to Westeros' shores, while Drogon is one of the three dragons born from petrified dragon eggs from the Shadow Lands beyond Asshai. Aegon I mounted Balerion the Black Dread during the Targaryen Conquest of Westeros, and afterward, and Daenerys Targaryen rode Drogon when she came for the Iron Throne.