Gregor Clegane, aka The Mountain, is one of the most feared characters on HBO’s Game of Thrones. Before he is seen on screen, The Mountain’s brutal and evil reputation precedes him. His violent deeds are famous across Westeros and he is responsible for some of the show’s most violent kills.

However, what we see on the show regarding The Mountain is really only the tip of the iceberg. With so many characters and so little time, Game of Thrones can’t cover everything from George R.R Martin’s books. But if you want to know more about Westeros’ most dangerous man, here are some facts about The Mountain that were left out of the show.

10. His Illness

Gregor Clegane aka The Mountain in Game of Thrones

It’s an understatement to say that The Mountain has an anger problem. Yes, it is his job to maim, kill and torture, but he seems quick to violent anger in any situation. When Loras Tyrell defeated him in jousting, The Mountain beheaded his own horse. There’s even rumors he killed one of his own men for snoring loudly. So where does this anger come from?

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In the books, it’s hinted that The Mountain suffers migraines. He complains about constant, painful headaches which he tries to drown out with milk of the poppy. Though such headaches can be awful, it’s still no excuse for beheading your horse.

9. Kinslayer

The Hound in armor

In Westeros, it is said that kinslaying (killing your own family) is the worst crime of all. The Mountain doesn’t seem too concerned with which laws he’s breaking, so it’s no surprise he is a suspected kinslayer himself.

His brother, The Hound, was nearly a victim of The Mountain’s rage as a child, leaving him badly burned. It’s also suspected The Mountain is responsible for the death of their father as well as a sister and his first two wives. Though there are plenty of kinslayers in the story, Gregor is especially scary for seeming to do it just for fun.

8. His Keep

The Mountain is a busy guy, always out waging war and killing people. So it’s no surprise we never see him relaxing at his home. That’s probably for the best, as his keep is described as a pretty awful place.

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As you can imagine, anyone who shares the same roof as The Mountain is running the risk of an early death. There are whispers of servants mysteriously going missing and never being seen again. Dogs are even afraid to spend time there. Though unlikely we’ll see it, it could make for a creepy setting on the show.

7. Siege Of The Riverlands

In season one, there’s a scene in which Ned Stark is being told of the raiding parties in the Riverlands led by The Mountain. These attacks have been ordered by Tywin Lannister after Catelyn Stark captured Tyrion.

Though the show gives a hint at the carnage The Mountain is inflicting in these lands, the book goes into much greater detail. As well as raping and pillaging the farmlands, The Mountain also attacked several Riverland lords with equal brutality. These attacks help to make The Mountain the most barbaric warrior during the War of the Five Kings.

6. Battle Of The Mummer’s Ford

Game of Thrones the Brotherhood Without banners

As deadly as The Mountain has been on the show, we’ve yet to see him in battle. One of the earliest indications of his ruthlessness in this respect comes in response to his attack on the Riverlands.

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An injured Ned Stark sends Beric Dondarrion and his men to bring The Mountain to justice. This proves to be a trap and Dondarrion’s party is ambushed. Though not a major battle in the grand scheme of things, it would have been a spectacle to see The Mountain ride into battle instead of just hearing the stories.

5. His Run-Ins With Beric Dondarrion

Beric Dondarron on Game of Thrones

The Mountain killed Beric Dondarrion at the Mummer’s Ford, but he didn’t stay dead. Beric was resurrected by Thoros of Myr and the Lord of Light. Throughout the show and book series, Beric is killed and brought back several times.

The show credits The Mountain with that first kill, but it’s not the last time these two crossed paths. When hunting Dondarrion’s “brotherhood without banners”, The Mountain kills the outlaw again, only for him to be resurrected again. It could have become a nice ongoing joke in the show, with The Mountain getting increasingly frustrated having to kill Beric over and over.

4. Torture Of Vargo Hoat

Locke threatens Jaime Lannister with a big knife in Game of Thrones season 3

Under the Lannister's orders, The Mountain seems to have a talent and affection for torture. We’ve seen hints of this in the show, especially with the undead version of The Mountain. However, his methods for Vargo Hoat in the books are truly gory.

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Hoat is a sellsword and the man responsible for taking Jamie Lannister’s hand. In the show, his counterpart Locke is similar though manages to escape this horrible fate. In the books, The Mountain infiltrates Hoat’s castle then proceeds to dismember him piece by piece over the course of months. Adding to that, he forces Hoat to eat whatever it cut off.

3. The Tavern Story

Polliver at table in Game of Thrones

There are many stories of The Mountain’s brutality featured in the show, but perhaps his most vicious act is left out.

Arya overhears one of The Mountain’s men telling about a tavern they visited where the friendly tavern keeper annoyed The Mountain. As punishment, The Mountain paid the man a coin then rapes his daughter before handing the girl over to his men. When the girl’s brother tries to intervene, he is killed. Then The Mountain demands the man repay the coin as he was unsatisfied with the experience.

It may be the most vile act of evil presented in the series.

2. His Painful End

The Viper fights the Mountain in GOT

The Mountain’s most famous moment is his fight with Oberyn Martell. The book and show depict this similarly, including the fact that The Mountain was poisoned during the face-off. In the show, The Mountain is in some sort of coma while Qyburn experiments on him. The book version of The Mountain does not get off so easy.

The slow acting poison Oberyn used was meant to kill the victim as slowly and painfully as possible – and it works. The Mountain’s cries of pain can be heard all throughout the castle until it is announced that he is dead. Or is he?

1. Robert Strong

Game of Thrones - The Mountain after resurrection

While The Mountain might technically be dead in both the show and the books, the books at least try to play coy about the whole reanimation subject. Once The Mountain has supposedly died, Qyburn introduces a new member of the Kingsguards, the enormous Robert Strong.

Though unconfirmed, it’s pretty obvious Strong is some undead version of The Mountain. Also, since Strong never speaks or removes his helmet, it’s rumored The Mountain is now headless. The show fully embraces the zombie Mountain, never mentioning Strong. But it is a fun, creepy addition that book fans miss.

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