The prequel to “Game of Thrones’’ is set to forge its own storytelling path. “House of the Dragon” has a new set of characters and a more diverse writing and directing team. The prequel takes place two centuries before the events of the original series, which ended its hit eight-season run in May 2019. “House of the Dragon” is based on George R.R. Martin’s book “Fire and Blood.” The series focuses on House Targaryen, made famous in “Game of Thrones” by Emilia Clarke’s Daenerys and her fearsome dragons. “House of the Dragon” begins Sunday on HBO and will be available to stream on HBO Max.