Name: Gregor Clegane
Experience: 100 (Legendary)
Agility d6; Smarts d4; Spirit d8; Strength d12+1; Vigor d10
Pace 6; Parry 7; Charisma –6; Toughness 11 (3)
Hindrances: Arrogant, Bloodthirsty, Mean
Edges: Brawny, Berserk, Brawler, Nerves of Steel, Combat Reflexes, Mighty Grip, Bruiser, Frenzy, Hard to Kill, Strong Willed, Killer Instinct, No Mercy
Skills: Fighting d10, Intimidation d12, Notice d4, Riding d6, Stealth d4, Taunt d6
Inventory: Great Sword (Str+d10), Plate Armor (Armor +3), Closed Helmet (Armor +3)
The only new Edge here is Mighty Grip, which allows for the user to use a two handed weapon in one hand at a –2 instead of a –4 and negates the –1 Parry, as his fight with Oberyn was almost entirely done with one hand.
His Hindrances are self-explanatory for anyone that's seen the show, but let's look at those Edges. Now, if there's ever a man that deserved Brawny, it's Gregor motherf*cking Clegane. I think his actor is something like 6'6" in the show and people still complain that he's too short. Berserk is a little bit more of a stretch, but he gets riled right the hell up when he fights. Once he starts, it takes a lot of effort to stop. Brawler, Bruiser, and his monstrous Strength are all also rather apparent (SPOILERS (NO SERIOUSLY, SPOILERS (He crushes his opponent's head in by squeezing it over the course of a round, maybe two. Even with a Called Shot, that's a lot of Strength))). Killer Instinct and No Mercy just make it easier for him to end whoever he happens to be fighting.
Lastly, that bit of Riding is from the first season when he jousted his brother (who has a Riding of d8, I might add), so it was worth noting.
I left his Smarts at a d4 because he doesn't seem particularly bright. Not that he needs to be, but it seems unfair to have someone that unreasonably strong be intelligent in any capacity. That's my only point of iffy contention.
There you have it: The Mountain. Leave questions, comments, etc. below. Avoid books spoilers, please, as I've not yet read them.