[Warning: This story contains spoilers for the sixth episode of Game of Thrones' seventh season, "Beyond the Wall."]

Like clockwork, Game of Thrones delivers the biggest thrills of the year in its penultimate installment: Ned's death in season one, the Battle of the Blackwater in season two, the Red Wedding in season three, the Battle at Castle Black in season four, "Hardhome" in season five (which was technically the third-to-last episode that year, but let's not pick nits) and the Battle of the Bastards in season six. Anyone wondering if season seven would buck the trend, wonder no more.

In keeping with tradition, season seven's penultimate episode, "Beyond the Wall," undoubtedly featured the most important moment of the season thus far — more than one moment, really. The breathtaking and giant-size episode (clocking in at more than 70 minutes) featured the season's biggest battle scene by far, which is saying something; the biggest Jon (Kit Harington) and Daenerys (Emilia Clarke) scene by far, which is also saying something, as well as the biggest dragon scene of the season by far — which, once again...well, you get the picture.

Really, it's two massive dragon sequences, both of which are linked in death. Entering "Beyond the Wall," virtually everyone expected to lose at least one main character, if not many more. Of the main players who passed beyond the Wall at the end of "Eastwatch," only one of them lost their life: Thoros of Myr (Paul Kaye), afforded a relatively peaceful (and somewhat ironic) end as the fire priest froze to death — only after he was brutalized by a zombie bear, of course, but that's neither here nor there. The rest of the hunting party emerged from the episode with their lives intact, which in and of itself would have been the biggest surprise of the hour, if not for the fact that an entirely different character lost his life: Viserion, one of Daenerys Targaryen's three dragons.

In what will go down as one of the most chilling scenes in Game of Thrones history, Daenerys and her fire-breathing children soared into the realm beyond the Wall in order to save Jon Snow and his allies, fulfilling one of the show's core promises: ice versus fire, and plenty of it. Viewers will not soon forget the moment they first laid eyes upon dragons incinerating wights on a battlefield made of ice, nor will they forget the battle's harrowing turn, as the Night King tossed a massive ice lance into the air and dropped a dragon from the sky. The elation of Daenerys flying in to rescue Jon, just in the nick of time, is matched only by the sheer horror of watching one of her dragons bleed out from high above, dropping and sinking into the frozen waters below.

As if Viserion's death wasn't traumatic enough for both Daenerys and viewers alike, the Night King added devastating insult to injury mere moments later. In the final scene of the episode, the White Walkers' resolute commander walked directly up to Viserion, placing his hand on the fallen beast's snout (a haunting mirror image of Jon's moment with Drogon last week), and raised it from the dead. That's right: as if the White Walkers didn't have enough power on their side already, now they also have an undead dragon in their possession. Winter is here with an added twist of fire, and the forecast for all in Westeros includes torrential amounts of devastation. 

There are some silver linings in Viserion's death and subsequent resurrection, including the fact that it seemingly answers one of the show's longest-running riddles: "The dragon has three heads." Most fans agreed Daenerys and Jon were two of the prophesied characters who would ride dragons by the end of the series, but there has never been a clean common consensus on the third dragon rider. Now, it looks like we have the very unexpected answer: the Night King.

But he's only the rider for now. Remember what the Three-Eyed Raven told Bran Stark (Isaac Hempstead Wright) all the way back in season four: "You will never walk again...but you will fly." Bran has long been discussed as one of the potential characters to fly a dragon some day, and now the stage is set for the young Raven to fulfill his destiny, using his great gifts as a warg to seize control over the undead Viserion from the Night King's influence. Consider it nothing more than a theory for now, and certainly one that won't pan out until much closer to the end of the series, if it ever pans out at all.

Another silver lining: Jon and Daenerys are finally on the same page. "You have to see it to know," she tells Jon about why she doesn't regret making the journey north, even though it cost her one of the most precious entities in her life. "Now I know." The Dragon Queen is more committed now than ever before to the cause of defeating the White Walkers, as much for vengeance as it is because she finally understands there's no greater threat to Westeros than the Army of the Dead. 

In return, Jon pledges his cause to Daenerys, referring to her as "my Queen." He stops short of bending the knee, purely because he's too wounded to perform the physical act, but Jon's promise to Don't-Call-Her-Dany comes with the implication that he won't be the King in the North for much longer — though given other recent revelations (not to mention the rapidly escalating nature of his relationship with Daenerys), Jon might be a king of another sort before long. 

Yet another silver lining of the expedition north (which, we can now all agree, was an ill-advised idea, given that it cost mankind a living, breathing nuclear bomb; seriously, Jon and his allies couldn't scoop up the first guy who got mauled by the bear and called it a day?): a clear idea of how to defeat the White Walkers. Leave it to Beric Dondarrion (Richard Dormer), now on his last life thanks to Thoros' death, to come up with the answer. Before the dragons make their grand entrance, and even before the big battle commences, Jon kills a White Walker, which results in the monster's undead minions immediately crumbling to the ground. The group theorizes that if a White Walker dies, the wights who were brought back to life under its spell will fall as well. Further, Beric comes out with the idea that defeating the Night King directly will lead to all of the wights dropping dead (like, permanently dead), since he's the one who is ultimately responsible for all of their resurrections. The road to the end is clear, then: if the Night King falls, all of the White Walkers will fall. Sounds simple enough on paper, but in practice? With an ice dragon on his side? Maybe not so easy.

For now, as hard as it is, there's more on the mind than just the White Walkers and the death of a dragon. There's only one episode remaining in season seven. Jon Snow and his allies are returning south with a captured wight in tow. Daenerys is already on board to fight the war against the monsters who killed her child. Now, the crew must convince Cersei Lannister (Lena Headey) to put her war for the throne on hold in favor of fighting the only war that truly matters. Last we checked in with Cersei, she was amenable to the idea of an alliance with the Dragon Queen, though she made it clear to her brother Jaime (Nikolaj Coster-Waldau) that she would only entertain those notions of peace for so long. 

Meanwhile, how ready is Daenerys to move on from pursuing her birthright? At one moment in the episode, Dany furiously rejects Tyrion's (Peter Dinklage) attempts to bring up questions about lines of successions. All season long, we have seen how much Daenerys desires to reclaim what once belonged to her ancestors. The tragedy of losing Viserion, and the gravity of what she saw beyond the Wall, should keep her priorities in line through much of the end of the series. The question is, how much will she lower her guard — low enough to allow Cersei a shot at killing her rival queen, or just enough to keep one eye on her own enemy?

In other words, as much as we should fear the march of the Night King, he's endgame material. It's the clash of queens we should be most excited about as we prepare for the season seven finale.

There's another clash brewing as we look toward next week's season finale: the feud between Sansa (Sophie Turner) and Arya (Maisie Williams). In "Beyond the Wall," the Stark sisters grow more and more bitter toward one another, to the point where it looks like Arya is truly thinking about physically harming Sansa. It's a testament to the feral nature Arya has nurtured over the past several seasons, speaking to the idea that there's no going home for the killer occasionally known as No One. For her part, Sansa is being forced to confront the idea that she wants power more than she's willing to admit. These are important notes for both characters, but the physical danger between the two feels a bit far given how much they've grown over the course of Thrones. Are we really expected to believe Sansa's story will end in murder, with her own sister holding the knife? And are we really expected to believe that both Sansa and Arya can't see through Littlefinger's (Aidan Gillen) transparent schemes? Look toward the finale to see if there's any justification to what's been one of the more sullen storylines of season seven. 

A few other notes from the episode:

• The action moved so fast that there was almost no time to stop and smell the roses, but now that it's over, let's take a moment to appreciate all of the many great character interactions: Tormund (Kristofer Hivju) bonding with the Hound (Rory McCann) over their shared connection with Brienne of Tarth (Gwendoline Christie); the Brotherhood giving Gendry (Joe Dempsie) a hard time over his bad blood about the leech of it all; Ser Jorah (Iain Glen) absolving Jon of any guilt over possessing Longclaw, House Mormont's ancestral sword; Jon and Beric stopping to appreciate their mutual brushes with death; and Beric and Thoros' final touching scenes together, one in which the red priest was alive, and one in which the Lightning Lord sent his old friend off to meet the Lord of Light. 

• Who else thought we were losing Tormund in the thick of that battle? It was the Game of Thrones equivalent of the scene from Aliens in which the xenomorphs pull Private Hudson underneath the floorboards. Thankfully, Tormund survived the encounter, and one wonders if we should consider the wildling one of the safest characters on the board now. After all, how in seven hells can Game of Thrones top that moment if the show ever wants to give Tormund a glorious death?

• He wasn't one of the Eastwatch elite, but he's another prominent character who met his maker all the same: Benjen Stark (Joseph Mawle), the human-wight hybrid who resurfaced in season six for the first time since disappearing in season one. His return here was very short-lived indeed, coming back just to save Jon from certain doom, only to fall beneath the weight of the wights a few moments later. At least Jon can carry forward with some closure from here on out.

Watch the video below for the Game of Thrones cast's preview of season seven's battles.

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