Ryan Condal is pulling out all the stops for House of the Dragon Season 3. Producing the third season of the Game of Thrones prequel series took 314 shooting days, more than 25 tons of propane, hundreds of actors and countless practical sets.

The first episode is expected to dive right into the Battle of the Gullet, which Condal teased will be quite epic during a first look at the highly anticipated season at ATX TV Festival over the weekend.

“So much of this [first] episode is practical,” Condal said. “You’re in the water; there are multiple ships interacting that are real physical sets, and the fire and the dragons and all these things knitted together just seem like it’s all happening in the same place at the same time … Of course, up to the audience to decide what they think of the episode, but just the things that we had to engineer and figure out how to do just to make this episode of television — it was pretty damn crazy.”

One of the biggest feats, which Condal thinks is more intense than nearly anything ever attempted in the Game of Thrones universe, is the naval portion of the battle.

“I think the big thing for this was the wet tank. So we have two tanks that are involved in the making of this. There’s a dry tank, which is when the ships are basically sailing. There are these gimbals that they built. They rock and they sort of pitch and yaw with the motion of the sea. Then we bring the water in digitally afterwards,” he described. “Some of the action takes place where we needed actually interactive water, so that people could fall in and certain other things [could] happen, and that was the part that we had to really engineer and figure out how to do, because in medieval combat, most of the naval battles we’re used to seeing, there’s gunpowder involved. In this world, there is none, so you got to get really close to each other to be able to attack with ranged weapons, and sometimes there’s ramming involved and boarding planks and all that stuff. So it was all that kind of interactivity that we had to work out to make it feel like it was real.”

In fact, Condal is willing to wager it’s one of the craziest episodes of television ever made. And yes, he knows that’s a tall order.

“I realize that might now be written on my tombstone, but I do think really just from a process perspective [it’s true],” he laughed. “It really is this amazing achievement of filmmaking on an artistic level, from all the crafts and crew that go into it … I think that’s going to be the surprise to everybody. We live in this era where really you can kind of do anything on film, and I think a lot of our brains just go, ‘Oh, that’s all just CG.'”

He added: “A lot of people are making big TV now, but it’s the biggest thing we’ve ever done, for sure.”

During the hour-long panel, the audience inside the Paramount Theatre in Austin, Texas was treated to multiple looks at the series. HBO debuted the first full trailer for the season in the room before releasing it the next day, in addition to a behind-the-scenes sizzle reel and a snippet from what Condal vaguely explained happened in “the first act” of the premiere episode, featuring Alyn of Hull (Abubakar Salim) and Corlys Velaryon (Steve Toussaint) in battle.

Season 2 left off “at the cusp of the precipice” of this looming battle, Condal said. He and the creative team have slowly been building toward this moment since the very first season, and now audiences will finally get to see the payoff.

“Season 1, we had to introduce this very complex, multi-layered family. Three generations of this family, sometimes of multiple different actors playing the characters so that everybody understood all the underpinnings of this kind of generational feud that was in the slow boil that would lead to Alys and Rhaenyra and their side of the family really kicking off the sport,” he said. “We didn’t want to have everybody talking about that [in] past tense. We want to show how that all happened, which is why we did Season 1 sort of in two parts, and then Season 2 was kind of the slow boil to war.”

Whatever is to come of this battle, it’ll almost surely bring about catastrophe and death for everyone involved. Condal said he was excited to dig into the type of “mutually assured destruction” that the show’s predecessor didn’t.

“I think the thing this show contends with that the original Game of Thrones did not contend with, at least until the very end, is this idea of there are nuclear weapons in play, and there are nuclear weapons in play on both sides. So really you have this classic Cold War standoff of mutually assured destruction. Of course, the characters in the show would not have those words, but we as a modern audience that can see that [do],” he explained. “So the war really kicks off in Season 2, but it’s done in fits and starts, because nobody wants to make the big move that is going to break down the wrath of [the dragon] Vhagar or Daemon, because they realize that if it goes too far, you could just have ash left over. But, of course, that builds and builds and builds, and at some point the cork comes off the champagne bottle, and that’s where we begin here in Season 3.”

Condal also teased plenty of dragons, both old and new.

“There is a lot of dragon action,” he promised. “There are new ones that we haven’t really spent any time with at all that you’ll be very excited to see, and some old favorites come back in and get lots of exciting screen time and action.”

That said, viewers who have become fond of the dragons might not be thrilled about where this story is headed.

“Everybody at the beginning plans this as they’ve learned as students of war, where you’re talking about who has what army and what houses behind it, but as it goes into its darker and darker days, this story becomes very much about who has what dragon, how many we have on our side, and how can we use them to kill the other dragons to try to win. That’s very much where this story is going. You will see that starting to play out this season.”