As HBO calls the banners for the beginning of Game of Thrones Season 7, the best way (besides Binge Mode) to set the scene for Sunday’s premiere is to revisit the last seconds of Season 6.

To review: That’s the Mother of Dragons sailing away from the newly renamed Bay of Dragons on a dragon-prowed ship flying a dragon-sigil sail, as three actual dragons swoop and soar overhead. In case the motif wasn’t obvious, one last dragon cry rings out after the fade to black. To paraphrase George Costanza: Dragons are what they’re indicating there.

When we last saw Daenerys, she’d become the closest thing to a superpower in Westeros without yet returning to its shores. On top of her horde of Dothraki and Unsullied, Dany has the help of the Tyrells, Ellaria and the Sand Snakes, and the younger Greyjoys, all of whom have let her lease their fleets as glorified ferries. In the core four of Tyrion, Varys, Missandei, and Grey Worm, she has a dream team of trusted advisers who could curb some of her Aerysesque, self-owning impulses. And maybe most important, she has a monopoly on winged, nigh-indestructible death-bringers whose proven game plan against any enemy is to kill it with fire.

Yet even assuming her secret nephew up north is more worried about White Walkers than the Iron Throne, Dany’s path to King’s Landing isn’t completely clear. There are several obstacles standing between her and the nonergonomic workspace she’s always wanted: Euron, whose marriage proposal was preempted by his nephew and niece; Littlefinger’s latest plotting; Jon’s lineage, which, if revealed, could counter her own claim; and, of course, Cersei, along with her one-handed/decomposed bodyguards and whatever forces the Lannisters have left in the wake of Tywin’s twins undoing decades of his work. And if she clears all of those hurdles, she’ll still have to handle the Night King and Co.

On the other hand, dragons.

If Dany were a playable character in an online game of thrones, we would say that she needs to be nerfed. To this point, Thrones has thrived on checks and balances among contenders for the crown, whose fortunes have shifted with each alliance and double-cross. Each of those aspiring rulers has been susceptible to takedowns not only by their rivals inside the Seven Kingdoms, but — largely unbeknownst to them — by the Others north of the Wall. If drama depends on conflict, then an overpowered player endangers the series’ suspense.

As the show’s endgame gets going, one of its greatest remaining mysteries is how it will maintain tension when one character has consolidated so much might, including sole possession of Westeros’s heat-leaking superweapons. Assuming showrunners David Benioff and D.B. Weiss don’t want their remaining 13 episodes to be about Dany dunking on everyone and delivering a Draymond Green crotch kick to the Night King, they’ll have to cast some doubt on her destiny. We need to believe that Dany can be defeated. And for that twist to be convincing, at least one dragon must die.

The slaver-slaughtering clip I posted above (from last season’s second-to-last episode, "Battle of the Bastards") gave us a glimpse of what the "Dany dunking" scenario would look like. If anything, it understated her pets’ capacity for carnage, given that Rhaegal and Viserion had long been confined to the catacombs, and that all of the dragons have undergone a growth spurt since Season 6. It doesn’t seem like so long ago that Drogon, Rhaegal, and Viserion were either egg-sized or out of control. Now they’re enormous, and they do what Dany says. According to one of Season 7’s directors, Matt Shakman, Drogon (the biggest of the three) is now as big as a Boeing 747 and barfs flames 30 feet in diameter, wide enough to simultaneously incinerate more than four Zombie Gregors laid end to end.

There’s plenty of precedent for dragon-related destruction in the Targaryens’ greatest hits, most notably the so-called "Field of Fire," in which Aegon the Conqueror (the founder of the Targaryens’ Westerosi dynasty) deployed all three of his dragons — Balerion, Vhagar, and Meraxes — at once for the first and only time, against an army that outnumbered his own conscripted soldiers 5–1. Four thousand of Aegon’s enemies burned, and the survivors said "Uncle" and bent the knee, provided they still had one. You may also remember Balerion from his work at Harrenhal, where Aegon skipped the expected siege and ordered his mount to melt the fortress’s towers from above. Walls don’t work against dragons, which makes them useful as scouts even when they aren’t busy burninating.

Even though both Balerion and Vhagar lived in an era of near-constant combat (and eventually, dragon-on-dragon violence), they fought on for close to two centuries and Balerion died of old age. That bodes well for Dany’s dragons, who have no natural rivals. It’s easy to imagine a Sherman’s March–style rampage into enemy territory, followed by a Dothraki/Unsullied assault on softened-up defenses. Nor does it seem as if the dragons would be daunted by the White Walkers’ undead army. Wights aren’t fans of fire.

But even dragons have bad days. As George R. R. Martin wrote many missed deadlines ago, "It is no easy thing to slay a dragon, but it can be done." Even smallfolk can kill dragons — as long as those dragons are chained and indoors, and hundreds or thousands of the attackers are willing to be burned alive in the process. If the dragon can climb out of range, a war of attrition won’t work, but any place not protected by scales — which haven’t hardened fully on Dany’s adolescent dragon brood — are vulnerable to pointy objects.

Surface-to-air weaponry isn’t Westeros’s strong suit, and airborne dragons aren’t easy targets, but Meraxes met her end via a bolt in the eye from a Dornish proto-catapult. With luck and skill, a dragon at low altitude or on land can be felled by a spear or a fire-resistant weirwood arrow. (Weirwood: It’s not just for carving creepy faces.) In theory, there should be a simple solution to the altitude problem: fly high. But bad weather — which should be the default forecast in the Lands of Always Winter — can ground dragons, bringing them within reach of short-range projectiles. And if Dany cedes control of Rhaegal and Viserion to lieutenants with Targaryen blood, they might make a rookie rider mistake. Based on what we’ve seen of his battle tactics, Jon would totally land a dragon and continue the fight on foot rather than safely spewing fire from above.

We’re not done with ways for dragons to die. If confrontation fails, there’s always sorcery, stealth, and poison. In the books, Euron claims to have recovered a dragon horn used by the ancient Valyrians to control the creatures; although it’s a little late for a deus ex dragon horn to appear on the show, his introduction did establish that he’d made unspecified strange discoveries during his far-reaching travels. During Aegon’s Conquest, Brandon Snow offered to sneak into the Targaryen camp under cover of darkness and slay the beasts while they slept. And although that plan was vetoed, some say that much later, the Maesters found a way to rid the world of dragons until Dany’s eggs hatched. Perhaps Sam will stumble across the key to killing dragons in his studies at the Citadel. Or maybe Dany’s seemingly unstoppable swarm, like Stannis’s army on its long slog to Winterfell, will fall prey to more mundane challenges, like a lack of supply lines and the fallout from a host of half-naked horsemen seeing snow for the first time. Dragons (and horses) get hungry, and winter weather could make quick passage impossible. If word reaches Cersei that Dany has her sights set on the Red Keep, she could raze the ground in Dany’s path, slowing her approach or forcing her to halt. (She might starve a few farmers while she’s at it, but Cersei’s not known for putting the populace first.)

Most likely of all, though, is that Dany’s dragons will meet their elemental opposites or be forced to turn on each other. While the book series’ titular "ice" and "fire" might refer to a team-up (or tryst) between Jon and Dany, they could also allude to a showdown between dragons whose temperatures sit at opposing extremes. In the books, Old Nan’s tales tell of ice dragons that grow larger than the fire-breathers. They wouldn’t be the first alleged legend to show up where the wild things are. And if you don’t have an ice dragon, a wight dragon will do. If the Night King kills and reanimates Drogon or his smaller siblings, the White Walkers will be back in business. We’ve seen that turnabout before.

As Cersei said in Season 1, winning and dying are the only outcomes in this quest for supremacy. As Season 7 starts, Daenerys seems closer to sealing the deal than any other character has come. But the past six seasons have taught us that no one in Westeros is safe, especially those who seem to be the strongest. Broadcast schedules being what they are, we know that victory can’t come until 2018, which means it’s too soon for Daenerys to run the table. And in light of that timing, it might not be the best omen that her dragons are all named after relatives who are already dead.

Disclosure: HBO is an initial investor in The Ringer.