[Caution: Spoilers for Game of Thrones Season 7 Episode 4 below.]

Last week, we mentioned how the visual effects team behind Game of Thrones always opt to use real fire instead of computer-generated animation. Last night, for what showrunners are dubbing "The Loot Train Battle," we saw this effort quite literally take off in one of the most technically complex episodes yet.

Because, well, dragons.

If we’ve learned anything from these fantastic behind-the-scenes videos, it’s that much of these effects are practical, and the guys behind them just truly love blowing shit up. But last night took it to another level—the episode set the record for most stuntmen burned in a single shot (20).

It also meant spraying an eco-friendly dye over the set dressing to make the objects appear charred or burnt. Dressers would wheel-barrow in carts of ash to spread about the scene’s surface.

Peter Marley, a props worker, explained the difficulties the production design team faced throughout the episode. “Because the entire sequence is a wagon train," he explains, "it involves 27 wagons and we have to reshuffle the entire set constantly, which means dressing 180 degrees or 360, depending on the camera movement.”

Screen_shot_2017-08-07_at_4Credit: HBO

The camera team had an even more monumental task. Luckily, they had every toy you could ever ask for to complete it. These included up to eight cameras, three different tracking vehicles equipped with steady rigs to keep the camera movement smooth, and a few innovative pieces of equipment to get the dragon’s swooping, acrobatic POV shots.

Speaking of dragons, the showrunners felt the only way they could simulate the incredible footage of Daenerys Targaryen’s torrential air-mounted attack was through speed. Those shots were achieved by using two different camera platforms: Spidercam, which is basically a camera rigged to a cable run between two construction cranes that can then be moved up to 70 mph from one end to the other; and FlyCam, which employs a super tricked out, horse-powered drone to get shots at a much faster speed than a regular drone. 

Screen_shot_2017-08-07_at_4Credit: HBO

In the end, as is the case with many episodes of Game of Thrones, the brunt of the work came down to the visual effects artists. This particular one, however, required far more VFX work than any that had aired before.

Just how much work did it take? Well, in the entirety of Season 6, there were eleven shots of Daenerys riding a dragon. In last night’s episode alone, there over 80. That’s where the green screen comes in. Emilia Clarke rode a motion base that was animated to fly in concert with the animation of the dragon.