A 'House of the Dragon' cinematographer broke down the dragon rampage in episode seven. He watched 12 stunt people being set on fire with a flamethrower.

• The final scenes of "House of the Dragon" episode seven may be pivotal for the series' civil war.
• In the episode, Rhaenyra attempts to recruit more dragonriders, but the plan goes wrong.
• Cinematographer Vanja Černjul broke down how the dragon ceremony-turned-massacre was filmed.

Warning: Major spoilers ahead for season two, episode seven of "House of the Dragon."

The massacre scene at the end of "House of the Dragon" episode seven may be brutal to watch, but a cinematographer told Business Insider that it was "unpleasant" to film, too.

In the latest episodes of the hit "Game of Thrones" prequel, Rhaenyra Targaryen (Emma D'Arcy) tries to build a team of dragonriders to help her win the war against her stepfamily.

Rhaenyra has the dragons but needs to recruit people from the Valryian bloodline — the only humans who can bond with dragons.

After Addam of Hull , Corlys Velaryon's (Steve Touissant) secret bastard son, is able to bond with Seasmoke, Rhaenyra calls for other bastards to come to her base in Dragonstone and attempt to become dragonriders, too.

At the end of the episode, Rhaenyra takes a large group of recruits to the second-biggest dragon in the land, Vermithor . She gives them vague instructions on how to claim the beast, before using soldiers to trap them in the cave.

Unsurprisingly, things immediately take a dark turn.

Vermithor starts attacking, breathing fire at, and eating multiple recruits.

After much bloodshed, Hugh Hammer (Kieran Bew) claims Vermithor and Ulf White (Tom Bennett) claims Silverwing in another section of the cave.

Vanja Černjul, the cinematographer for episodes seven and eight, said the dragon's rampage was the "most Game of Thronesy scene" they shot.

The early seasons of "Game of Thrones" were well-known for their epic, grotesque medieval fight scenes — something that the "House of the Dragon" team appear to be trying to emulate.

"I think in one shot, we had 12 stunt people on fire," Černjul said.

Here's how the cast and crew brought the chaotic scene to life.

Černjul said it was 'unpleasant' to watch people be lit on fire with a flamethrower

Černjul said that the scene was precisely planned and storyboarded months in advance, giving the visual effects team time to create an animation of what the scene would look like for the directors.

"The characters looked like the actors. It was quite amazing. It's almost sad that nobody will ever see those amazing animations," Černjul said.

The "scary part" was that the crew didn't have much time to shoot such a crucial scene, Černjul added.

The dragon cave scenes were shot over two days on a bluescreen stage at Warner Bros' Leavesden Studios in Watford, England.

Despite the planning, Černjul said there were still some challenges during shooting, because the scene used practical effects, including fire, to simulate the dragon's attack.

For instance, for safety reasons, the stunt people could only be on fire for eight seconds, so they had to be quick when filming.

"Even though you are aware that it's a stunt people, that it's some of the best stunt people in the world, when you see people on fire, it's really unpleasant to watch," Černjul said. "Imagine 12 people lit at one time with a flame thrower."

Part of the scene is shot from Hugh Hammer's point of view to capture the 'danger' of the scene

Černjul said episode seven director, Loni Peristere, had a request early on: To do an entire scene in one shot from a character's point of view.

Hugh Hammer was the chosen character.

In season two, Hugh is introduced as an ordinary blacksmith, but in episode seven, he tells his wife that he is the child of a Targaryen and aims to claim a dragon so that he has the power to protect her.

Hugh claims his mother was an aunt of King Viserys I (Paddy Considine) and Daemon Targaryen (Matt Smith), a plot point at odds with "Fire and Blood," the novel the series is based on.

Amid the chaos, Hugh, who is very important later in the war in "Fire and Blood," bonds with Vermithor, which is likely why Hugh was chosen as the scene's main character.

Černjul said he and the director wanted the massacre scene to be "centered" on Hugh's experience.

"We wanted to feel as subjective as possible so you are with this character's experience in this hellscape and danger," Černjul said.

"We always wanted to be close and wide, close enough that you feel proximity to the actor, you feel like you're with the actor."

He added: "Wider so you can still see the environment, you still can feel what's happening."

Ulf White's dragon scene was filmed on the same bluescreen stage

After Hugh claims his dragon, Ulf White becomes the new focus.

In episode three, Ulf tells a group of bar patrons that his father was Baelon the Brave, making him another illegitimate sibling of King Viserys and Daemon.

Ulf reluctantly goes to Dragonstone to claim a dragon and somehow escapes Vermithor's savage attack. However, as he stumbles through the cave, he comes across another dragon, Silverwing.

Silverwing doesn't kill Ulf and instead lets the bastard be his rider.

Černjul said scene was shot on the same stage as the previous one. For the massacre scene, a raised platform was put up to represent the jetty platform that leads into the dragon cave.

"We removed the jetty and lit it in a different way," Černjul said about how they filmed Ulf's scene.

Černjul said Peristere was integral for helping the actors know what the dragon was doing in both scenes, because they only had a small puppet to visualize the dragon.

Peristere used a special audio system that Černjul called "the voice of god" to talk to each actor directly while filming.

"He was talking to them in real time, and then he would basically almost turn into a dragon," Černjul said. "He would start when the dragon was closer to the actors or close to Rhaenyra, he would start breathing like a dragon just to give them a sense of the proximity to this creature."

Overall Černjul said he was happy with how the scene turned out.

"I think it's quite incredible," he said. "It wasn't always a hundred percent, but we got very close to how it was planned."

"House of the Dragon" season two airs Sundays at 9 p.m. ET on HBO and is streaming on Max .