Game of Thrones: Oral history of the Mountain vs. Viper fight

Game of Thrones delivered one of its most exhilarating and distressing scenes to date in season 4, when the acrobatic Oberyn "The Red Viper" Martell (Pedro Pascal) faced off against the hulking Gregor "The Mountain" Clegane (Hafþór Björnsson). The fight is staged as a trial by combat for Tyrion Lannister (Peter Dinklage), but it's also personal: Oberyn agrees to champion Tyrion's cause in the hope of exacting revenge against the Mountain, who raped and murdered his sister, Elia, and slaughtered her children.

In typical Thrones fashion, the fight ends in tragedy, and for a show packed with gut-wrenching deaths, poor Oberyn's demise is perhaps one of the most traumatic. Since then, the gory scene has lived on in infamy, spawning parodies and even Bud Light commercials.

Ahead of Game of Thrones' final season, EW gathered the cast and crew to get the inside intel on TV's most notorious head-squish.

ALEX GRAVES (Director): There were two big things [going into the scene]. My biggest concern was that you not see the end coming and that you would become confident that the Viper was going to win. And then the second was that I [wanted] the fighting to be more acrobatic and musical than the earlier fights in the show had been.

PEDRO PASCAL (The Red Viper): They set me up with an instructor of wushu martial arts in Los Angeles that I trained with. And then I trained with the incredible team that they had on season 4 and this brilliant double named Liang Yang, who is a wushu master who's doing the helicopter spin-jumps in the air. I apologize to the fans: That was not me. But I did learn the fight, and when you see my face, it's me!

GRAVES: The Viper was kind of like Frank Sinatra walking into Game of Thrones. He was like this slick guy, and he was known for being a very acrobatic, deft fighter. So immediately [we thought], "Oh, cool, we won't be doing classical jousting work, he can get airborne." And we really ran with that.

The crew shot the fight over several sweltering days at the Hotel Belvedere, an abandoned seaside resort in Dubrovnik, Croatia, that was damaged during the Croatian war of independence.

INDIRA VARMA (Ellaria Sand): The heat was unbearable, but I was really lucky because I was barely dressed compared to everyone else in their corsets. [Laughs] I remember [Björnsson] was dressed in all that armor, and he had to be fed extra food because the pounds were just dropping off him in that heat and [with] the exhausting nature of the fight. They were all knackered. That was grueling for them, but I just sat there and enjoyed the sun, trying not to burn.

HAFÞÓR BJÖRNSSON (The Mountain): It was grueling work, going through the fight again and again and again in full armor in the sweltering heat in Croatia — but what a scene!

TOMMY DUNNE (Weapons master): That fight was so fierce. The sun was heating up the ground, and they were hitting each other. Each weapon, gosh, it was taking so much damage — because they're really hitting hard and hitting well and hitting the ground, and you'd have timber break. Or you'd have a little bit of damage on the side of the blade, [so] you'd take it out and put the next one in. You had to make sure everyone was looking well, so we resprayed them halfway through with some blood.

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The tiny Viper slowly turns the battle to his advantage and ultimately triumphs — before the Mountain surprises him. The result is one of Thrones' goriest, most heartbreaking deaths, as Clegane squashes Martell's head with his bare hands.

PASCAL: The squish! The squish that I will gladly take to my grave!

The effects team made a hyperrealistic cast of Pascal's head and ran a line of fake blood inside, so that when Björnsson pressed down with his thumbs, blood would leak from the eye sockets.

PASCAL: The funniest thing about it is that you never see yourself three-dimensionally that way. In photographs or staring into the mirror, you do not get a real sense of what you look like until there's a very detail-oriented cast of you. I remember just sitting there and staring at it and being like, "Holy sh—, I look so much like my dad." I learned that from staring at the cast of my head, right before watching it repeatedly get squished.

BJÖRNSSON: It was a different experience [filming the squish]. As an actor, you have to be able to put yourself into the character, since your job is literally making the character and the situation he is in believable. But the VFX and the prosthetics, expertly done by the HBO team, made it really gruesome, even for me.

PASCAL: It was a little like [the beheading of the android played by] Ian Holm in Alien with the tubing and the squirting and stuff, except that it was red blood rather than white juice. It's like, "Oh, that's my face. And there goes my face. Goodbye, face."

GRAVES: To be honest, you don't really see the head get crushed on camera. Everyone always gets on me about that, and I'm like, "It's a sound effect! It's not on camera!" And they're like, "No, it is!" They don't care. They felt it happen. [But] I thought we showed some restraint there. I had no desire to see more than we were already seeing. [Laughs]

VARMA: I literally had one take for my reaction shot to the fight. My coverage was, like, the last thing of the day, like, "We're losing the light!" So I had one take with nothing in the eye line, so I think my look of horror is me going, "What?! Only one go at this?!" [Laughs]

PASCAL: The best part about it was post-death, because it was so hot. They very apologetically made me lie down in a cool pool of blood with prosthetic chunks placed all over my face for this above shot, which was actually me lying there. It was all very cool to the touch, and it was relaxing. So there I am, dead, and I fell dead asleep.

GRAVES: We did one shot where the Mountain rolls over exhausted, and we laid raw meat all over a stunt actor's face with the high-wide crane shot. So the blood puddle's spreading, and there's meat all over his face. It was pretty horrible.

VARMA: After [wrapping], Pedro and I just jumped in the sea, and very cheekily we met a guy who had a boat down there, and we hitchhiked back by boat instead of us taking transport back to the hotel. So that was the coolest way to end that fight scene. It was a very romantic escape.

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