Game of Thrones may be over on the small screen, but book fans know that there is still plenty more to come in Westeros... and plenty more that has already happened, too. Like most adaptations, A Song Of Ice And Fire suffered through some serious editing to make George R R Martin's books appropriate for TV - leaving book fans with a much deeper knowledge of this world, these characters, and lots more Westerosi lore.

However, even just reading the novels and watching the HBO series wouldn't be enough to truly immerse yourself in this world, as like many other authors with extensive world-building skills, Martin has continued to add details to his universe in other formats. While he's not a Twitter-fan like J.K. Rowling, Martin has definitely dropped some new info in interviews, on his blog, and of course, in his companion books (A World of Ice And Fire, and Fire And Blood). From these, we've pulled together some of the most fascinated tidbits about Game of Thrones... that are definitely canon, and definitely not in the series (or the novels).

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Unicorns Exist (And Are Ridden Like Horses)

Admittedly, there is a small mention of unicorns within the novels (although sadly, the HBO production budget clearly didn't allow for Dragons, Direwolves, and Unicorns... A Dance With Dragons contains a couple of small mentions of the one-horned creatures; one in a dream, and a wildling helm made from the head of a unicorn. However, what's not in the novels is the fact that unicorns are the common mount of choice for the Skagosi, the men living on the island of Skagos. These men are said to not only ride unicorns, but to trade their horns occasionally, although some Maesters claim that the unicorns are a myth, and the horns are from whale bone. Most interestingly, Martin has said in an interview that he's got plans for unicorns in the coming novels, so watch this space...

Tywin Lannister Was The Youngest Hand In History...

Tywin Lannister's history isn't explored in great depth in the series, although fans got to read a whole lot more about him in the books. Book fans know, then, that Tywin and the Mad King were friends in their youth, and that when Aerys II took the throne, he actually got rid of many of his father's court and replaced them with his friends... including Tywin, who was named Hand of the King. One little tidbit that book fans may not be aware of, though, is that this happened when Tywin was only 20, making him the youngest ever to be appointed Hand to the King.

... And Knighted The Mad King

Aerys' admiration for Tywin started long before he named him hand, though. The two met as young boys, when Tywin was a royal page to the Targaryens in King's Landing. In fact, Aerys was such a close friend to Tywin that when he 'won his spurs' (the right to be knighted) at the age of 16, he asked for Tywin (recently made a knight himself) to be the one to do the honors. Of course, all of this is a story that Tywin was sure to hush up after Aerys turned out the way he did...

 Why The Red Wedding Happened

Robb Stark at the Red Wedding in Game of Thrones

By the end of the series, the Red Wedding was far from the most brutal moment of the show... but it's definitely still up there, as Robb and Catelyn Stark and their people are massacred while under guest-right. Fans were shocked when it first happened, but Martin has since revealed that he planned it from the start - and all because Ned Stark died. In interviews, Martin has said that he needed to kill Robb and his bride in order to prevent fans from assuming that this was going to be a predictable story of the son avenging his father's death (or his son avenging him!).

There Are Only 277 Valyrian Steel Blades Left

Valyrian steel in Westeros in Game of Thrones

Valyrian Steel is a massively important weapon in the world of Westeros, and only the best swords are made of this incredible metal. Until other swords, it is significantly stronger and holds its edge for longer, despite use. And, of course, it is one of the few weapons capable of killing a White Walker.

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In the books, several characters throw out guesses about how many Valyrian Steel weapons still exist, and only a few confirmed swords and daggers show up - but in the companion books, it's revealed that there are exactly 277 in Westeros... at least, according to the records of Archmaester Thurgood.

That Daenerys Isn't The First Of Her Name

Yup, despite being constantly hailed as 'Daenerys of the House Targaryen, the First of Her Name, The Unburnt, Queen of the Andals, the Rhoynar and the First Men, Queen of Meereen, Khaleesi of the Great Grass Sea, Protector of the Realm, Lady Regent of the Seven Kingdoms, Breaker of Chains, and Mother of Dragons'... Daenerys isn't actually the first Targaryen of her name. There are two earlier women who share her name: the daughter of King Jaehaerys I Targaryen (and in line to marry the heir and become Queen), and the daughter of Aegon IV (and married to the Prince of Dorne). Technically, neither were Queen of the Seven Kingdoms, making Daenerys the first true Queen of her name, but she's definitely not the only one to get close to that throne - and still not sit on it!

Lady Crane May Have Been A Skinchanger

Lady Crane backstage at the play in Game of Thrones

Lady Crane doesn't actually appear in the books at all, at least, not under this name. In the novels, the actress that Arya meets is known as Lady Stork, but the name was changed (like several others) for the show. However, the show version is, presumably, a woman of House Crane, and Martin added an interesting detail about these women in his companion books: that they are said to be skinchangers, descended from Rose of Red Lake (who is a child of Garth Greenhand). The original Crane, Rose herself, could change into a bird - and perhaps this lives on in the Lady Crane of the theater, although her skinchanging simply allows her to be a master of her craft.

Joffrey Isn't The First Lannister King With A Thirst For Violence

Joffrey Baratheon with a crossbow on Game of Thrones

Joffrey Baratheon was everyone's most-hated character (at least, until Ramsay Bolton appeared on the scene), and a huge reason for this is that he was vindictive and loved inflicting pain on the people around him - physical and emotional.

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In one particularly hideous scene, Joffrey is sent prostitutes, and makes them physically torture each other, eventually actually killing them himself. A shocking predilection, to be sure, but apparently, one that runs in the Lannister bloodline. King Tyrion II was known as Tyrion the Tormentor, and according to A World of Ice And Fire 'his true delight was torture, and it was whispered of him that he desired no woman unless he first made her bleed'.

Where Daenerys Got Her Dragon Eggs

When Daenerys married Drogo, she was given a gift - three dragon eggs, thought to be fossilized. Of course, fans soon learn that there is still life in these eggs, as Daenerys is able to hatch them and become the mother of dragons... but where did these eggs come from? In Fire and Blood, Martin offers up a story that seems to be connected - that of Elissa Farman. Elissa was originally a close friend of Rhaena Targaryen, but couldn't stand staying on Dragonstone forever, and after Rhaena refused to help her fund her exploratory voyages, Elissa stole three dragon eggs, ran away, and sold the eggs in order to buy herself a ship and disappear. It's not 100% confirmed that these are the same eggs that Daenerys is given, but considering how protective the Targaryens were over their eggs, it's certainly likely.

 Ser Duncan The Tall Is Brienne of Tarth’s Ancestor

Brienne looking out over Winterfell in Game of Thrones

And finally, a little addition to the ancestry of everyone's favorite knight: Ser Brienne of Tarth. Known for her impressive height, it may not come as too much of a surprise that Martin confirmed that she is a descendant of none other than Ser Duncan The Tall. A former Lord Commander of the Kingsguard, Ser Duncan has a rich history, and is generally considered one of the more honorable knights of Westeros history. As well as being related to Ser Brienne, in a fantastic Easter Egg within the books, Brienne actually uses his original arms (insignia) on her own shield in order to travel incognito... never realizing that she is actually using the symbol of her own ancestry!

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