Varys: In its time, the Dragonpit was a marvel of the world. Full-grown Targaryen dragons nested beneath its massive dome and even on the darkest nights the walls seemed to glow with the fire of the great beasts inside.
Qyburn: As had the site's previous occupant, the Sept of Remembrance, when Maegor the Cruel blasted it with dragonfire during morning prayers. The screams of the dying men echoed through King's Landing all day and a pall of ash and smoke hung over the city for a week.
Varys: But as it dissipated, so too did the rebellion of the Faith Militant. The Sept of Remembrance fades from memory and Maegor decided to replace a monument to the gods with a monument to his family: the Dragonpit.
Qyburn: Labor proved elusive, however, for after the Red Keep was finished, Maegor had hosted a three-day feast for all builders, stonemasons, and carpenters who had worked to build it. At its conclusion, he slaughtered them, so that only he would know the castle's secrets. So many men fled the construction of the Dragonpit that Maegor was forced to employ the prisoners of the city dungeons, supplemented by skilled and ignorant builders from across the Narrow Sea.
Varys: For more than a century, the Targaryens housed their dragons in the Dragonpit. But dragons are not horses to be stabled or hounds to be kenneled. With each generation, the dragons became less...less massive, less swift, less long-lived.
Qyburn: And less invulnerable. During the Dance of Dragons, two Targaryen factions killed a handful of their family's dragons while fighting each other. A frenzied mob even broke into the Dragonpit and slaughtered the five dragons chained there, though the last managed to bring down the roof of the great dome on its assailants. The dragons never recovered their former strength or numbers. Perhaps their line had been too broken or perhaps others intervened to break it further. But the last dragon grew no larger than a cat and its death earned Aegon, Third of His Name, the epithet "Dragonbane".
Varys: What is a Dragonpit without dragons? The roof remained where it had fallen, the great bronze doors rusted and fell off their hinges. Prostitutes cavorted where fantastic creatures had once fed and slept. Then came Daenerys. Now dragons once again darken the sky, but they will never darken the Dragonpit again. Daenerys has learned the folly of chaining her dragons. The Dragonpit is and will remain a ruin of a bygone age, when kings and queens flew high above their countrymen.
- The video ends by depicting Daenerys's three dragons flying over the Dragonpit - but Viserion was killed in the TV series, in the episode right before the meeting there. It's possible that the production team didn't inform the animator of this in advance, to avoid major spoilers while Season 7 was still being completed.
- The depiction of the Dragonpit in this video is much closer to the colossal megastructure it is described as being in the books. When it appeared in live-action in the Season 7 finale, the TV series filmed in a real Roman arena - which could not possibly fit multiple adult dragons within it (in the episode, Drogon by himself visibly takes up most of the space in it). Of course, the ruins of the Dragonpit are depicted in the episode, and it could be argued that the undamaged structure was much larger.
- The Dragonpit was built large enough to hold 40 living dragons, in cells ringing the walls. There were never that many Targaryen dragons at one time - the most were during the Dance of the Dragons, when there were 20 living dragons - but Maegor apparently had the foresight to leave room to grow their population (during Maegor's time there were perhaps half a dozen dragons, most of them juveniles).
- Maegor's destruction of the Sept of Remembrance and construction of the Dragonpit is described in detail in the prequel novella The Sons of the Dragon, publicly released in 2017 a few weeks before the Season 7 Blu-ray set containing this video was released.
- The video says that after so few laborers were willing to construct the Dragonpit, after Maegor killed all the builders of the Red Keep, that he had to resort to hiring workers from across the Narrow Sea. Specifically, Maegor actually press-ganged criminals from the city's dungeons to act as common laborers on its construction, under the supervision of masons from the Free Cities: specifically, from Myr and Volantis.
- Varys points out that subsequent generations of Targaryen dragons grew smaller and less powerful, until the last was a stunted, sickly creature no bigger than a dog or cat - and then ponders that "perhaps others intervened", alluding to a theory from the novels that the Maesters may have poisoned the dragons over time, because dragons represent a world of magic opposed to the world of science they are trying to build. Even in the books, however, this is just a theory (by Archmaester Marwyn), and may not be true: it is equally possible that the dragons were simply affected by compound inbreeding with each passing generation. There were only three original Targaryen dragons, and similar to their Targaryen masters, this heavy amount of incestuous breeding may have led to various health problems over time. After the Dance of the Dragons there were only four living dragons: two simply disappeared with their deaths unconfirmed, one adult (Silverwing) who had gone mad with grief, and one hatchling born during the war. There simply wasn't a stable breeding population left, and the last dragon, stunted and sickly, died 22 years later during the reign of Aegon III (despite his efforts to hatch more of them).
- The books have indeed mentioned the detail that in later generations, the shattered ruins of the Dragonpit are occupied only by prostitutes and their patrons - the structure is located atop the Hill of Rhaenys in King's Landing, and the Street of Silk - the up-scale brothel district catering to wealthy nobles and merchants - is located near the top of the hill as well, not far away. In the novels, this became a minor point contributing to the Wildfire subplot at the Battle of the Blackwater: the Mad King had the Alchemists' Guild hide caches of wildfire all over the city, such as under the Great Sept of Baelor, as well as in the abandoned cellars of the Dragonpit. This cache was rediscovered when a whore and her patron accidentally fell through a weak floor into a store-room below, alerting Tyrion to the existence of this and all the other hidden wildfire stockpiles. Had they not found these old stockpiles, Tyrion would never have been able to produce enough wildfire to use against Stannis's attacking fleet. The TV show simplified this to just say that the Alchemists's Guild worked all day and night for weeks to make enough wildfire.
- King Maegor the Cruel
- Balerion (indirectly mentioned)
- King Aegon III Targaryen
- Last dragon
- Queen Daenerys Targaryen
- Faith Militant uprising
- Dance of the Dragons