GAME OF THRONES: HBO Developing More Prequels, Including TALES OF DUNK AND EGG There's some exciting news for Game of Thrones fans today as HBO is said to be moving forward with even more prequels, including Tales of Dunk and Egg. Find out more details on that after the jump... JoshWilding | 1/22/2021 Variety reports that HBO is developing another Game of Thrones prequel, this time based on the Tales of Dunk and Egg from author George R.R. Martin. Those follow the adventures of Ser Duncan the Tall and a young Aegon V Targaryen, and the story is set 90 years before the events of the main series.