The Fallen.

.200 years before the Game of Thrones, and 172 years before the death of Mad King Aerys and the birth of his daughter, Daenerys 'Stormborn' Targaryen. 'House of the Dragon' follows the infamous Dance of the Dragons that resulted in the deaths of many of the Targaryens' dragons, and themselves. It was a result of the murky line of succession after King Viserys Targareyn, first of his name, died and his rightful heir was heavily disputed. All because his heir... Was a woman.