HBO’s Game of Thrones universe is only getting bigger.

The network’s Head of Drama Series and Films Francesca Orsi announced HBO is developing multiple Game of Thrones spinoff series based on the works of George R.R. Martin, joining prequel series House of the Dragon and the upcoming Knight of the Seven Kingdoms.

Per Deadline, Orsi said, “We have other spinoffs that we’re working on right now, one of which — which I won’t get into — is very promising, and it is still the Targaryen line.”

“There’s a number of other spinoffs, we can’t really guarantee what’s going to go forward,” she continued. “But we are very big budget on the other ones.”

Orsi did not specify which of Martin’s tales will be adapted to the screen, but if HBO is developing a series about another era of the Targaryen lineage, it will likely focus on Aegon’s Conquest.

There have been many reports about the long-rumored series, which will be set 300 years before the events of Game of Thrones, focusing on Aegon I Targaryen. Previous reports note the project will explore how Aegon conquered six of the seven kingdoms of Westeros, making him the first ruler to sit on the Iron Throne.

Martin wrote about Aegon’s Conquest in his 2018 Westerosi history book, Fire & Blood.

Orsi did not reveal much information about the other series that are in development, but she did share that they will have a much bigger production budget than A Knight of the Seven Kingdoms, which she described as being “the most intimate” series in development.

A Knight of the Seven Kingdoms is based on Martin’s Tales of Dunk and Egg, a fantasy trilogy following Ser Duncan the Tall (Peter Claffey) and his loyal squire “Egg” (Dexter Sol Ansell) as they travel Westeros during a divisive political climate.

“You’re going to be so impressed by Peter Claffey and Dexter Sol Ansell as Dunk and Egg, the two leads, the sort of brotherhood, the paternal nature between Dunk and this young man,” she said. “So much so that we’re already planning on how do we build this for the three seasons in total. We’re not picking it up officially, but it’s looking very good. We’re looking at it as a holistic piece, Seasons 2 and 3, because there’s three novellas.”

A Knight of the Seven Kingdoms is set to premiere on HBO June 15.

Orsi also revealed that House of the Dragon Season 3, which is beginning production soon, will kick off with the highly anticipated and bloody Battle of the Gullet.

A premiere date for Season 3 has not been announced yet.