A totally serious and scientific look at dragons in House of the Dragon

The world of House of the Dragon, the Game of Thrones prequel series, looks and feels a lot different than the last time viewers visited Westeros. We're now 200 years earlier in history at a time when the Targaryen empire was at the peak of its power. It's a time of great prosperity and peace, and also a time where the most amount of dragons roamed the skies above the Seven Realms.

Miguel Sapochnik, a co-showrunner on the fantasy drama with Ryan Condal, became the cast's own living encyclopedia of fire-breathers. Emily Carey, the actress behind young Alicent Hightower, confirms he actually ran his own impromptu dragon lecture with Condal and the cast.

"I remember in rehearsal, we sat down and had a conversation about how one would interact with a dragon," Carey tells EW. "We had this whole in-depth thing about living in a world with dragons... It's something that, even as an actor, I hadn't thought about. But especially coming from the original show, you see these characters interacting with dragons in a very different way. It was such an interesting topic of conversation. We genuinely spent at least an hour talking as a group."

Sapochnik and Condal pulled details of this time period in Westeros from George R.R. Martin's Fire & Blood, the history of House Targaryen that served as the basis for House of the Dragon. But they still had to fill in a lot of blanks. Fire & Blood isn't a fleshed-out literary narrative like Martin's A Song of Ice & Fire books that spawned HBO's Game of Thrones, but is more like a historical document that glosses over the main events.

In between filming on House of the Dragon at the U.K.'s Leavesden Studios in December, Sapochnik explains what they came up with.

Three types of dragons

House of the Dragon chronicles the events leading up to and during the Dance of the Dragons, the name given by the poets of Westeros to a gruesome civil war that tore House Targaryen asunder. Princess Rhaenyra Targaryen, played in her youth by Milly Alcock and as an adult by Emma D'Arcy, is named the sole heir to the Iron Throne by her father, King Viserys I (Paddy Considine). But later years see the king conceive of a son, Aegon (Tom Glynn-Carney), which splits an already fraught empire in two over the matter of succession.

The reason this war is so destructive is because most of the Targaryens in power have dragons. Rhaenyra rides Syrax; her uncle, Prince Daemon Targaryen (Matt Smith), another claimant to the throne, mounts Caraxes; and her aunt, Princess Rhaenys Targaryen (Eve Best), wife of Lord Corlys Velaryon (Steve Toussaint), rides "the Red Queen," Meleys. To quote a line from Martin's text in Fire & Blood, "It is no easy thing for a man to be a dragonslayer. But dragons can kill dragons, and have."

Over the course of a calendar year with three meetings a week, five designers got to work on creating the looks of all the dragons for House of the Dragon, even beyond the first season. Each one often crafted concept art illustrations for two of these creatures at the same time.

According to Sapochnik, one artist would work on the look for Syrax, while another would work on Caraxes. "Then, basically, they would switch and design them on top of each other's stuff," the showrunner notes. One presentation book consisting of all the designers' work contains approximately 900, if not 1,000 pieces of concept art — just for the dragons.

The challenge was twofold: creating dragons that looked like they were in the same biological family as Drogon, Rhaegal, and Viserion — the three drakes hatched by Emilia Clarke's Daenerys Targaryen in Game of Thrones — yet not so similar that they all looked like their ancestral twins.

"It's one of the most satisfying processes because there was no limit placed on how we did it," Sapochnik says.

A veteran of Game of Thrones who directed some of the original show's most memorable episodes, Sapochnik found a way to make these beasts of myth feel distinct. "I came up with the idea that there were three types of dragons," he explains. "There's the dragons that are dinosaur-like; they have a big bridge on their nose. There are the dragons that are canine, which usually have the convex feel to them; they feel wolf-like. And then, there's the dragons that are like horses, which are somewhere in between. So, I've got a wolf skull, a horse skull, and a T-Rex skull, and designed the same dragon on top of them to see how the skull changed the features of the dragon."

Dragons never stop growing

The biggest dragon viewers will meet on House of the Dragon is Vhagar, Sapochnik confirms.

Vhagar was once the she-beast of Visenya Targaryen, sister of Aegon I Targaryen, who rode the monolith over from Old Valyria during the conquering of Westeros. Laena Velaryon (Savannah Steyn), the eldest daughter of Corlys and Rhaenys, rides Vhagar during this time period in House of the Dragon.

"She's like a cantankerous old lady," Sapochnik describes the leviathan. "Bits of her are falling off, and getting her in the air is a nightmare. When she's up and running, she's like a B52 bomber. She's stunning and a force to be reckoned with. Landing her is a nightmare."

Vhagar is the prime example of how the showrunners thought about the life cycle of dragons. "One of the most interesting things, for me, was trying to figure out dragon sizes and dragon anthropology," Sapochnik says. "What we came up with is dragons never stop growing. At some point in their prime, they're this fully formed incredible beast, and then they start to get, essentially, cancer. Bits of them break off, they start to become flaky, and they become so big that they break their legs when they land and that's what kills them. What kills them is their own weight."

Again, Sapochnik looked to dinosaurs when thinking about creatures that become so massive that they can no longer sustain themselves. "It's not just about the size of the dragon," he adds, "it's about the state of the dragon."

How to train your dragon

On top of the three types of dragons, Sapochnik also makes distinctions between the domesticated and the wild, untamed dragons that roam Westeros. Dragonstone, the ancestral seat of Targaryen power, built on an active volcano, is one site teaming with fire-breathers. There are three wild dragons designed for the show that won't make appearances in season 1 but remain the showrunner's favorite to date.

"We had to sit down and figure out, how do you train a dragon?" Sapochnik says. "You can watch the movie, which is really good. How To Train Your Dragon is a great reference point. But how you train your dragon became all sorts of things. Like, do they give them implants when they're little that then later become the hooks for the reins? So, they get little pricks to figure out when they're first given to their rider. Their riders are also kids who don't know how to deal with the dragon. And then, as they grow older, they don't need the reins anymore and the reins become extraneous, etc. etc. It's nerd city. I had more fun doing that."

In the world of Westeros, as written by Martin in Fire & Blood, it became common practice to place a dragon egg in the cradle of a newborn Targaryen in the hopes that rider and dragon would grow alongside each other, strengthening that bond. A warehouse housing the show's props at Leavesden Studios, where the stage work was filmed, contains various multicolored dragon eggs created for House of the Dragon. Some are black, some are purple, some are pristine, and some have moss growing alongside the bottom.

A few of the younger cast members spent about five days on a Dragonpit set, filming with actors playing High Valyrian-speaking dragon handlers who teach Targaryen children how to bond with these creatures. Like how Daenerys used "dracarys" to command Drogon to shoot fire, High Valyrian is the language the Targaryens use to commune with dragons.

"We're in this big ditch, and there's a scene where I'm patting my dragon, but it was just a big blue cutout and then there was a big blue screen behind it," recalls Alcock, playing teenage Rhaenyra. "It just looked like we were at a really s----y music festival because it was a little lifted area that I would jump off. I would have to pat [the dragon]. Then Miguel was like, 'Can you smell it?' I was smelling this styrofoam, but I got the incentive, [like] you smell your dog or cat. It's a very human thing to form a connection."

According to D'Arcy, dragons sparked an "entire leather industry" in Westeros. Unlike in Game of Thrones, where dragons were extinct, House of the Dragon will see the production of saddles, each one distinct to the rider. A separate warehouse at Leavesden Studios contains these various seats constructed for each of the dragon-riding characters. Daemon's saddle for Caraxes is more Conan the Barbarian, with furs draped over the mount. Rhaenyra's saddle, by comparison, is more regal.

The power of dragons

The dragon/rider connection means different things to different cast members. For D'Arcy, who uses they/them pronouns, dragonriding is a means for Rhaenyra to enjoy the freedoms usually afforded to men in this medieval time.

"It's an emblem of identity for her," they say. "Rhaenyra is humming with Targaryen fire, and what does it mean if fire is your ally? Fire is this volatile thing that is hard to control, that is hypnotic, that is beautiful, that is both an agent of terror and an agent of transmutation. It functions by destruction, so that from the ashes, something new can exist. That's where my area of reflection was. What is it to live with all of that inside you? When do you have to dampen that? And when do you learn to trust that? But it's hard to bring a fire into a council chamber. It's difficult."

For Best, dragonriding speaks to the "wild" part of Rhaenys, who was dubbed "the Queen Who Never Was" after she was passed over for the throne in favor of Viserys because of her gender. "Connecting with the dragon is like connecting with everything about yourself and about life, about the world that is untamable," she says. "It's intuitive and non-political, but is animal and visceral."

King Viserys is the rare Targaryen who doesn't ride dragons. He once rode Balerion, the Black Dread, the dragon that once bonded with Aegon the Conqueror. But now the beast's skull sits at an altar in Kings Landing, surrounded by candlelight. Viserys often visits his old friend when he's in deep thought.

"I just think Viserys has an understanding of dragons," Considine says. "He actually sees them as very, very dangerous and a huge responsibility. He understands fully that it's these dragons that make the Targaryens powerful. He also has an understanding of their potential to destroy the world. He sees them as nuclear bombs in a way. I think Daemon would happily ride on dragons and torch everything, whereas Viserys is very much like, 'You have to behave responsibly with these creatures that we have' — with these weapons, really."

House of the Dragon premieres on HBO and HBO Max Aug. 21.

Subscribe to EW's West of Westeros podcast, which goes behind the making of House of the Dragon and the growing Game of Thrones universe. The podcast will launch Aug. 21.

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