HBO is moving forward with plans at the cabler to build a massive Game of Thrones cinematic universe, as three more spinoffs have just been put into development. Joining the prequel series House of the Dragon, the trio of new ideas will similarly be based on the literary works of author George R.R. Martin. The projects have yet to officially be ordered to series, so it remains to be seen if all three end up getting the green light.

Using the working title 9 Voyages, the first of the three new prequel concepts hails from Rome creator Bruno Heller. The story would follow Lord Corlys Velaryon, aka The Sea Snake, the Lord of the Tides and head of House Velaryon. It would also serve as a spinoff of House of the Dragon, as Lord Velaryon will appear in that series with Steve Toussaint in the role. Presumably, Toussaint would be featured in the same role in 9 Voyages.

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Another prequel series, dubbed 10,000 Ships, revolves around the warrior queen Princess Nymeria, a "revered ancestor of House Martell who founded the kingdom of Dorne (she became so legendary in the realm that two characters bore her name in the original series - Sand Snake Nymeria Sand and Arya's direwolf). Her story is set roughly 1,000 years before the events in Game of Thrones, making it much older on the Westeros timeline than any of the other previously announced projects in the works."

Meanwhile, the third pitch revealed for another prequel series, with no working title divulged, would be set in the notorious King's Landing slum of Flea Bottom, the "maze of tight streets in the capitol city where characters like Davos Seaworth and Gendry Baratheon were born." Nothing else has been revealed about this spinoff beyond that it would be another prequel, though a timeline wasn't specified.

Only one Game of Thrones spinoff has officially been greenlit. Previously, Naomi Watts starred in a pilot for Bloodmoon, a planned prequel series set 10,000 years before the events of the parent series. For unclear reasons, HBO passed on ordering the prequel to series, and the footage from the pilot has never been released. The show would have taken place in the Age of Heroes, revealing the foundation of the powerful Houses and the Long Night when the White Walkers first descended upon Westeros.

It's a different story with House of the Dragon, as HBO has officially ordered a 10-episode season of the spinoff. Based on Martin's Fire and Blood, the series tracks the beginning of the end for House Targaryen. Its starring cast includes Paddy Considine as Viserys Targaryen the First, Olivia Cooke as Alicient Hightower, Emma D'Arcy as Rhaenyra Targaryen, and Matt Smith as Daemon Targaryen. Production on the prequel series is scheduled to start in April.

Considering the backlash over the final season of Game of Thrones, it remains to be seen if the spinoffs will see the same levels of success. So many fans were disappointed in the popular HBO show's finale that a petition was launched to recreate the entire season from scratch with new writers. That obviously didn't happen, so it remains to be seen how many of these burned fans will be willing to give the franchise another shot with the spinoffs.

This news comes to us from The Hollywood Reporter.