Game of Thrones 'ice dragon' theory could send a chill around Westeros

*SPOILER ALERT* Fans have been re-reading George RR Martin's books for clues about a future battle

As season 7 of Game of Thrones starts to draw to a close, fans have been speculating about what kind of showdown they can expect when the show reaches its climax.

While most attention, for now, has been around Jon Snow's parentage, many have returned to the books for clues - in particular, the World of Ice and Fire.

There’s a theory floating around that the dramatic end game showdown will be between Danaerys and her dragons... and the Night King and his.

It sounds far-fetched, but if it’s to happen, the big question is how does the Night King get his hands on a dragon?

The first possibility is that he already has one.

Not only did Martin write a book sixteen years before Game of Thrones called The Ice Dragon, but the existence of them was alluded to in the books by Old Nan when she says “cold as the breath of the ice dragon," (you might laugh, but she was right about the direwolves and giants).

In the books, they’re also described by Maester Margate in The World of Ice and Fire in some detail: "Colossal beasts, many times larger than the dragons of Valyria... said to be made of living ice, with eyes of pale blue crystal and vast translucent wings through which the moon and stars can be glimpsed as they wheel across the sky.

"Whereas common dragons (if any dragon can truly be said to be common) breathe flame, ice dragons supposedly breathe cold, a chill so terrible that it can freeze a man solid in half a heartbeat."

So it’s more than possible that somewhere north of the Wall, the Night King has a dragon up his sleeve.

The more popular theory of how he could get his hands on a dragon, however, is that he could resurrect one.

Dani’s dragons seem invincible, but based on the show's history that doesn't mean a lot, and with three in the air right now it's very likely one will be a casualty.

Bronn came close to becoming a dragon slayer in season 7 episode 4, and Qyburn has seemingly developed a dragon-slaying weapon, so it’s only a matter of time before one of them breathes its last fiery breath.

It has also been speculated that Bran could warg into one but lose control, and see it fall into the hands of the Night King. As Bran was told in season four by the three-eyed raven: "You will never walk again... but you will fly."

Game of Thrones airs in the US on HBO every Sunday where it is simulcast in the UK on Sky Atlantic at 2am. It is repeated that same evening on both Sky Atlantic and NOW TV.

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