Game of Thrones fans know that dragons are awesome. Those flying, fire-breathing animals are everything fans could ever ask for — and in George R.R. Martin's world, we take these small victories. After last week's Lannister barbecue on Game of Thrones, fans are now also acutely aware of the damage these creatures can inflict as they mature. But, what if there was another magical animal that could easily best one of Dany's babies in a fight, without even breaking a figurative sweat? One long-running fan theory revolves around certain icy, mythical beasts that will make even Drogon quiver with fear. Ice dragons could potentially happen on Game of Thrones.
Unless fans have all collectively missed a massive flying hunk of ice somewhere in seven seasons, ice dragons are probably not trolling around yet. This of course means that if they do exist, they will have to be woken up or raised from a dormant state somewhere, somehow. And, there's a fairly good chance that they do exist. Ice dragons first came out of Martin's brain way before A Song of Ice and Fire was even written. Martin published a children's story called The Ice Dragon back in 1980, which told the tale of a little girl who befriends an ice dragon and saves her world from fire dragons' destruction. The world she lives in is not Westeros and there are no official connections between the two stories — but the ice dragon tales still appear in ASOIAF.
Fans of the series and the books may remember Old Nan, the older servant from Winterfell who cared for the Stark children in the first season of Game of Thrones. She was known for telling them tales of Westerosi myth and legend from time to time. In the books, Jon recalls her stories of ice dragons when he is at the Wall. Specifically, in A Dance With Dragons Jon recalls, “The wind was gusting, cold as the breath of the ice dragon in the tales Old Nan had told when Jon was a boy.” In the series, Old Nan tells Bran about ice spiders, which are certainly not ice dragons but they imply that there is a path that can lead to ice animals.
In Martin's companion guide to the series, The World of Ice and Fire: The Untold History of Westeros and Game of Thrones (page 294 if you are interested), there is a mention of ice dragons as well. This is definitely a more promising mention, since it directly connects to Game of Thrones' world. The entry is within the Shivering Sea history and describes ice dragons as "colossal beasts, many times larger than the dragons of Valyria." They are 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."
These terrifyingly beautiful creatures breathe cold, as opposed to fire. They can even "freeze a man solid in half a heartbeat." Basically, they would cause some major trouble, should they appear on GoT. This book also mentions that ice dragons supposedly melt when they are slain, so it is tough to find their remains to confirm their existence. Could a melted ice dragon (or several) have aided in the creation of the great wall? The wall is said to stand due to spells or magic, and dragons are about as magical as you can get.
The theory that seems to make the most sense in regards to how these mythical beasts will come about has to do with the impending white walker battle. It is entirely possible that one of Dany's dragons will actually be taken out in battle, giving the Night King the opportunity to turn the fallen dragon into one of his ice soldiers. After all, we have seen mammoths and horses join the army of the dead, so it is entirely possible that dead dragons can as well. In fact, when asked at the 2017 SXSW if a dragon wight was possible in the series, show runner David Benioff answered, "Maybe." That is as good as it gets for Game of Thrones fans wanting knowledge from these tight-lipped showrunners.
Seeing an ice dragon appear on Game of Thrones would also fulfill the ice and fire aspect of the series. If you take all of this into account, it's seeming more and more likely that fans will witness these legendary beasts. Keep your eyes peeled, because if it happens — it will likely happen soon.