After more than a year of speculation over potential Game of Thrones spinoffs, HBO has officially greenlit a pilot episode for a prequel series from showrunner Jane Goldman (X-Men: First Class, Kingsman: The Secret Service).

Now, George R.R. Martin—who co-created the project with Goodman—has suggested an ominous-sounding title for Thrones‘ first successor show.

In a post on his website, the A Song of Ice and Fire author seemed to tease a storyline centered on the dark and terrible winter of Westerosi lore when the White Walkers turned against their creators, the Children of the Forest, descended from the North and began killing everyone in their path.

“My vote would be The Long Night, which says it all, but I’d be surprised if that’s where we end up,” he wrote. “More likely HBO will want to work the phrase ‘game of thrones’ in there somewhere.”

Here’s HBO’s official description for the prequel:

Martin also revealed that there’s a chance we could be getting even more Thrones spinoff series.

“Three more Game of Thrones prequels, set in different periods and featuring different characters and storylines, remain in active development,” he wrote. “Everything I am told indicates that we could film at least one more pilot, and maybe more than one, in the years to come.”

Write to Megan McCluskey at [email protected].