Warning: SPOILERS ahead for the Game of Thrones season 7 premiere
The Game of Thrones season 7 premiere has set the field for the conflicts to come as the war for the Iron Throne heats up (adding a few dragons to the mix will do that). With only eight episodes this season instead of the usual ten, it'll be sooner rather than later that we'll see war break out between those still vying to rule the realm.
Exactly where season 7 goes from here is really anyone's guess, because the show has completely overtaken the published novels in terms of plot. Sure, there are some developments and more than a few characters from George R. R. Martin's A Song of Ice and Fire that have yet to appear in HBO's Game of Thrones, but given how speedily the series is moving towards its big finale, it just isn't possible for showrunners David Benioff and Dan Weiss to fit in everything.
Still, there's always a chance that more of what Martin has weaved into his epic saga could make its way into Game of Thrones. After all, the two versions of the story intend to reach the same conclusion, so even without a Lady Stoneheart or Young Griff, A Song of Ice and Fire and Game of Thrones must continue to share in at least some important plot beats.
This brings us to the season 7 premiere and two scenes, in which the show appeared to be laying the groundwork for two items only ever mentioned in the novels: Dragonbinder and the Horn of Winter. These horns have magical properties and were each created for a specific purpose. And just in case Game of Thrones is actually considering bringing either of these horns into the mix, we want to make sure you know as much about them as any book reader.
Dragonbinder, The Hellhorn
In the premiere, the recently anointed Queen of the Seven Kingdoms (well, three at best), Cersei is desperate for allies. The North remains in open rebellion, and with Highgarden and Dorne throwing in with the newly arrived dragon queen, the South isn't much help either. This leaves Cersei with few options -- one of which is Euron Greyjoy, a character more untrustworthy than Walder Frey and more dangerous than Ramsey Bolton.
When Cersei receives Euron in the throne room, he makes her an offer of marriage, saying that with their combined forces they could together easily crush their enemies. Cersei, however, declines, noting Euron's reputation as an oath breaker and murderer. Not at all deterred, Euron promises to return to King's Landing and ask again for her hand when he has delivered his "finest gift." It's that phrase -- "finest gift" -- that has book readers' wondering if just maybe Game of Thrones still plans on adapting a few of those extraneous elements from the novels.
During the kingsmoot in the fourth book, A Feast for Crows, when various Ironborn are vying for the Salt Throne and presenting their claims and offerings, Euron arrives with Dragonbinder -- a gleaming black horn, six feet long and bound with red gold and Valyrian steel. Said to be crafted from the horn of an actual dragon and discovered amidst the smoking ruins of Valyria, Dragonbinder is purported to have the power to control dragons (a claim later repeated by Moqorro, a red priest, giving it a touch of credence). When blown, the ancient Valyrian glyphs carved into its band glow white hot and the sound it makes is like a thousand screams. Those who hear it feel as if their bones are on fire and the man who blows it, one of Euron's sailors, collapses with blistered lips and blood seeping through his chest. That man later dies from the experience and when his body is examined by a maester, they discover his lungs are charred and blackened.
Dragonbinder immediately silences any of the other claimants to the Salt Throne, like Asha (known as Yara on the television show) and another Greyjoy uncle, Victarion, leading to Euron being crowned the undisputed King of the Iron Islands. He then gives the hellhorn to Victarion, whom he orders to sail to Meereen, present his offer of marriage to Daenerys, and return with her and her dragons.
Could Dragonbinder be the "finest gift" Euron is planning to present Cersei with in exchange for her hand in marriage? Maybe. A horn capable of seizing control of Daenerys' dragons would give an incredible advantage to a queen at risk of losing her kingdom to those dragons - at which point, how could Cersei refuse Euron? Then again, with absolutely no prior mention of such a horn, introducing something as powerful as Dragonbinder this late in game could come across a bit like a deus ex machina, solving Cersei's biggest hurdle in one fell swoop.
This also assumes that either Euron of Cersei could become the horn's owner, a tricky feat seeing as anyone who blows the horn dies. So even if Dragonbinder were introduced, there's no guarantee it'd become an advantage for Cersei. The inscription on the horn, according to Moqorro, reads: "I am Dragonbinder ... No mortal man should sound me and live ... Blood for fire, fire for blood." And with the invoking of the Targaryen words, it may be that only someone with dragon's blood can sound the horn and live, which leaves only two possible candidates: Daenerys or Jon.