Warning: This post contains spoilers for “Beyond the Wall,” the sixth episode in Game of Thrones’s seventh season. If you are not caught up on the series, stop reading now.

The death of a dragon in “Beyond the Wall,” the sixth episode in Game of Thrones's seventh season, highlighted just how little fans of the series really know about Daenerys’s three children. But for those itching to know more about the show’s dragons—alive and undead—the symbolism in their names offers clues about their true characters and hints at how they might behave in the future.

First, the dragon that died was Viserion. The show doesn’t make it very easy to distinguish Viserion from its sibling Rhaegal—Rhaegal is slightly greener on screen than Viserion—but if you watch closely you’ll see that Viserion was the one downed by the Night King’s spear.

Notably, this is the dragon named after Viserys, Daenerys’s power-hungry older brother. In the first season, Viserys sold his sister to Khal Drogo in exchange for an army he could use to take the Iron Throne. But after growing impatient with Drogo, Viserys threatened to kill his pregnant sister if the invasion didn’t begin immediately. Drogo, at his wit’s end, silenced Viserys’s whining with a pot of molten gold. In "Beyond the Wall," Viserion died, too. Like its namesake, Viserion is set to turn on Daenerys and Drogon, the dragon named after Drogo.

That leaves Rhaegal, named after Daenerys’s eldest brother—and Jon’s father—Rhaegar Targaryen. If anyone is going to ride Rhaegal it would make sense for it to be Jon, the only other living Targaryen in Westeros and the son of the dragon’s namesake. After all, Jon has already demonstrated an ability to put dragons at ease in “Eastwatch,” when he patted Drogon on the snout.

"Beyond the Wall" put to death the iteration of the Three-Headed Dragon theory that predicted Tyrion Lannister would be revealed as a hidden Targaryen and ride the third dragon into battle. But the theory will now almost certainly be fulfilled in a much more chilling way: with the Night King as the third rider.

It’s unclear how Viserion would behave as the Night King’s mount. Nerdist reported on how, in the books, Old Nan alluded to mythical ice dragons in stories she told Jon growing up. There’s also a constellation called the Ice Dragon, complete with a rider with a blue star for an eye that always points north. The World of Ice and Fire, the companion encyclopedia George R.R. Martin wrote to further detail his fantasy world, describes unverified reports of ice dragons over the Shivering Sea north of the wall. Sailors claim they are bigger than regular dragons, translucent, and breathe cold that “can freeze a man solid in half a heartbeat.”

Long before he started on his A Song of Ice and Fire series, Martin also wrote a children’s book called The Ice Dragon (though he has since insisted that his children’s book does not exist in the same sex-and-violence-crazed universe as his later novels). In the world of the children’s book, the good ice dragon defeats the evil fire-breathing dragons to save the story’s protagonist. Over at Vanity Fair, Joanna Robinson wondered if Viserion might end up being one of the good guys, writing that, "Now that we’ve seen two close-ups in the span of two episodes, of dragon eyes both brown and blue, will we eventually see one go white as Bran takes control of Viserion back from the Night King in Season 8?"

It remains to be seen which side will win in the Game of Thrones universe—but hopefully we'll have the answers by the time the series concludes in June.

This article has been updated for 2019.