Written by George R.R. Martin in collaboration with Elio Garcia and Linda Antonsson

It was Princess Rhaena, legend says, who put a dragon’s egg in Princess Alysanne’s cradle, just as she had for Prince Jaehaerys two years earlier. If those tales be true, from those eggs came the dragons Silverwing and Vermithor, whose names would be writ so large in the annals of the years to come.

- Fire and Blood "The Sons of the Dragon"

Like his father, Aenys Targaryen, the First of His Name, was given over to the flames in the yard at Dragonstone. His funeral was attended by his sons Viserys and Jaehaerys, twelve and seven years of age respectively, and his daughter Alysanne, five. His widow, Queen Alyssa, sang a dirge for him, and his own beloved Quicksilver set his pyre alight, though it was recorded that the dragons Vermithor and Silverwing added their own fire to hers.

- Fire and Blood "The Sons of the Dragon"

When at last Maegor returned to King’s Landing to seat himself again upon the Iron Throne, he was greeted with the news that his mother, Queen Visenya, had died. Moreover, in the confusion that followed the death of the Queen Dowager, Queen Alyssa and her children had made their escape from Dragonstone, with the dragons Vermithor and Silverwing…to where, no man could say. They had even gone so far as to steal Dark Sister as they fled.

- Fire and Blood "The Sons of the Dragon"

Prince Jaehaerys was fourteen years old when he claimed the throne; a handsome youth, skilled with lance and longbow, and a gifted rider. More, he rode a great bronze-and-tan beast called Vermithor, and his sister Alysanne, a maid of twelve, commanded her own dragon, Silverwing. “Maegor has only one dragon,” Lord Rogar told the stormlords. “Our prince has two.”

- Fire and Blood "The Sons of the Dragon"

Only Darklyn and Staunton had the courage to remain with Lord Towers to yield up the Red Keep when Prince Jaehaerys and his sisters, Rhaena and Alysanne, descended upon the castle on their dragons. The court chronicles tell us that as the young prince slid from the back of Vermithor, these “three leal lords” bent their knees before him to lay their swords at his feet, hailing him as king

- Fire and Blood "Prince into King: The Acension of Jaehaerys I"

Yet for all the splendor of the bride and groom, it was the arrival of Alyssa’s children that set King’s Landing to talking for years to come. King Jaehaerys and Princess Alysanne were the last to appear, descending from a bright sky on their dragons, Vermithor and Silverwing (the Dragonpit still lacked the great dome that would be its crowning glory, it must be recalled), their great leathern wings stirring up clouds of sand as they came down side by side, to the awe and terror of the gathered multitudes. (The oft-told tale that the arrival of the dragons caused the aged High Septon to soil his robes is likely only a calumny.)

- Fire and Blood "The Year of the Three Brides-49 AC"

That night, under cover of darkness, King Jaehaerys and Princess Alysanne mounted their dragons, Vermithor and Silverwing, and departed the Red Keep for the ancient Targaryen citadel below the Dragonmont. Reportedly the first words the young king spoke upon landing were, “I have need of a septon.”

- Fire and Blood "The Year of the Three Brides-49 AC"

King Jaehaerys I Targaryen returned to King’s Landing alone, on the wings of his dragon, Vermithor.

...

And when at last the sound of wings was heard, and a guardsman on the eastern walls caught sight of Vermithor’s bronze scales in the distance, there came a cheer that grew and grew and grew, rolling past the Red Keep’s walls, down Aegon’s High Hill, across the city, and well out into the countryside.

...

Jaehaerys did not land at once. Thrice he swept over the city, each time lower than before, giving every man and boy and barefoot wench in King’s Landing a chance to wave and shout and marvel. Only then did he bring Vermithor down in the yard before Maegor’s Holdfast, where the lords were waiting.

- Fire and Blood "A Time of Testing: The Realm Remade"

The young king—a boy no longer—soon dispelled his Grand Maester’s fear. As he slid gracefully from Vermithor’s back, he smiled. “It was as if the sun had broken through the clouds,” reported Lord Tully.

- Fire and Blood "A Time of Testing: The Realm Remade"

In answer, King Jaehaerys descended the Iron Throne and bade Lord Rogar follow him. He led his lordship from the hall to the inner ward where Vermithor was being fed. A bull had been slaughtered for his morning meal and lay upon the stones charred and smoking, for dragons always burn their meat before consuming it. Vermithor was feasting on the flesh, tearing loose great chunks of meat with each bite, but when the king approached with Lord Rogar, the dragon raised his head and gazed at them with eyes like pools of molten bronze. “He grows larger every day,” Jaehaerys said as he scratched the great wyrm under his jaw. “Keep your nieces and your nephews, my lord. Why would I need hostages? I have your word, that is all that I require.” But Grand Maester Benifer heard the words he did not speak. “Every man and maid and child in the stormlands is my hostage, whilst I ride him, His Grace said without saying,” wrote Benifer, “and Lord Rogar heard him plain.”

- Fire and Blood "A Time of Testing: The Realm Remade"

During the course of his long reign, Jaehaerys would spend more days and nights guesting with one lord or another, or holding audience in some market town or village, than at Dragonstone and the Red Keep combined. And oft as not, Alysanne was with him, her silvery dragon soaring beside his great beast of burnished bronze.

- Fire and Blood "Birth, Death, and Betrayal Under King Jaehaerys I"

Jaehaerys was resolved to do things differently. No more than one hundred men would accompany him on any progress; twenty knights, the rest men-at-arms and servants. “I do not need to ring myself about with swords so long as I ride Vermithor,” he said.

- Fire and Blood "Birth, Death, and Betrayal Under King Jaehaerys I"

Princess Aerea had known Vermithor and Silverwing during her time at court, but she had never been allowed too close to them. Here she could visit with the dragons as often as she liked; the hatchlings, the young drakes, her mother’s Dreamfyre…and greatest of them all, Balerion and Vhagar, huge and ancient and sleepy, but still terrifying when they woke and stirred and spread their wings.

- Fire and Blood "Birth, Death, and Betrayal Under King Jaehaerys I"

King Jaehaerys finally made his progress through the Vale of Arryn in 52 AC, calling at Gulltown, Runestone, Redfort, Longbow Hall, Heart’s Home, and the Gates of the Moon before flying Vermithor up the Giant’s Lance to the Eyrie, as Queen Visenya had done during the Conquest.

- Fire and Blood "Birth, Death, and Betrayal Under King Jaehaerys I"

And so he did. The coming of the new year saw the king taking to the sky again on Vermithor, this time for the riverlands.

- Fire and Blood "Birth, Death, and Betrayal Under King Jaehaerys I"

"Should the dragons turn up, anywhere from here to Yi Ti, we will demand their return. They were stolen from us, they are ours by right. If that demand should be denied, then we must needs go and get them. Take them back if we can, kill them if not. No hatchlings can hope to stand against Vermithor and Dreamfyre.”

- Fire and Blood "Birth, Death, and Betrayal Under King Jaehaerys I"

The unexpected arrival of Vermithor and Silverwing at Oldtown brought thousands to the streets to point and stare. No word of their coming had been sent ahead, and there were many in the city who were frightened, wondering what this might portend…none, mayhaps, more than Septon Mattheus, who turned pale when he was told. Jaehaerys brought down Vermithor on the wide marble plaza outside the Starry Sept, but it was his queen who made the city gasp when Silverwing alighted atop the Hightower itself, the beating of her wings fanning the flames of its famous beacon.

- Fire and Blood "Birth, Death, and Betrayal Under King Jaehaerys I"

Whilst awaiting his coming, Jaehaerys used the time to call at Bandallon, Three Towers, Uplands, and Honeyholt. He even flew Vermithor to the Arbor, where he sampled some of that island’s choicest wines.

- Fire and Blood "Birth, Death, and Betrayal Under King Jaehaerys I"

First, however, his lordship had to contend with a more contentious arrival. Dawn was breaking and Queen Alyssa’s body was not yet cold when Vermithor raised his head from where he had been coiled sleeping in the yard, and gave out with a roar that woke half of Storm’s End.

- Fire and Blood "Birth, Death, and Betrayal Under King Jaehaerys I"

All such preparations were thrown into disarray by the sudden and unexpected arrival of Rhaena Targaryen from Dragonstone. “It may well be that dragons somehow sense, and echo, the moods of their riders,” Septon Barth wrote, “for Dreamfyre came down out of the clouds like a raging storm that day, and Vermithor and Silverwing rose up and roared at her coming, suchwise that all of us who saw and heard were fearful that the dragons were about to fly at one another with flame and claw, and tear each other apart as Balerion once did to Quicksilver by the Gods Eye.”

- Fire and Blood "Birth, Death, and Betrayal Under King Jaehaerys I"

Just as she had when carrying Princess Daenerys, the queen refused to let the king cancel or postpone the trip, and sent him forth alone. Vermithor carried him across Westeros to the Golden Tooth, where the rest of his retinue caught up with him. From there His Grace visited Ashemark, the Crag, Kayce, Castamere, Tarbeck Hall, Lannisport and Casterly Rock, and Crakehall.

- Fire and Blood "Jaehaerys and Alysanne: Their Triumphs and Tragedies"

When word of her escape reached the Red Keep, the king pondered long and hard on chasing after Elissa Farman himself. No ship can sail as swiftly as a dragon flies, he reasoned; mayhaps Vermithor could find her where Lord Hightower’s ships could not. The very notion terrified Queen Alysanne, however. Even dragons cannot stay aloft forever, she pointed out, and such charts as existed of the Sunset Sea showed neither islands nor rocks to rest upon. Grand Maester Benifer and Septon Barth concurred, and against their opposition, His Grace reluctantly put the idea aside.

- Fire and Blood "Jaehaerys and Alysanne: Their Triumphs and Tragedies"

Three younger dragons soon joined the Black Dread under the Hill of Rhaenys, whilst Vermithor and Silverwing remained at the Red Keep, close to their riders.

- Fire and Blood "Jaehaerys and Alysanne: Their Triumphs and Tragedies"

If his Hand was not able to settle the matter at hand amicably, however, His Grace would have no choice but to come himself on Vermithor for what Barth termed “vigorous discussions.”

...

Only then was King Jaehaerys free to fly north with Vermithor. He and the queen reunited at Winterfell, after half a year apart.

...

After lingering in Winterfell for another fortnight, they made their way to Torrhen’s Square and thence to Barrowton, where Lord Dustin showed them the barrow of the First King and staged somewhat of a tourney in their honor, though it was a poor thing compared to the tourneys of the south. From there Vermithor and Silverwing bore Jaehaerys and Alysanne back again to King’s Landing.

- Fire and Blood "Jaehaerys and Alysanne: Their Triumphs and Tragedies"

The queen collapsed in the king’s arms, shaking so violently that some feared she had the Shivers too. Jaehaerys had her taken back to her own chambers and given milk of the poppy to help her sleep. Though near exhaustion, he went next to the yard and loosed Vermithor, then flew to Dragonstone to tell them there was no need for the hatchling after all.

- Fire and Blood "The Long Reign - Jaehaerys and Alysanne: Policy, Progeny, and Pain"

The smallfolk of the time called it Lord Rogar’s War, and that name is far more apt. Whilst the Lord of Storm’s End led five hundred men into the mountains, Jaehaerys Targaryen took to the air, on Vermithor. “He calls himself a vulture,” the king said, “but he does not fly. He hides. He should call himself the gopher.”

...

 Legend claimed the Vulture King had an impregnable mountain fastness, hidden in the clouds. Jaehaerys found no secret lair, only a dozen rude camps scattered here and there. One by one, Vermithor flamed them all, leaving the Vulture only ashes to return to.

- Fire and Blood "The Long Reign - Jaehaerys and Alysanne: Policy, Progeny, and Pain"

He would never have the chance. Jaehaerys Targaryen and his sons Aemon and Baelon had been waiting as well, and as Morion’s fleet beat its way across the Sea of Dorne, the dragons Vermithor, Caraxes, and Vhagar fell on them from out of the clouds. Shouts rang out, and the Dornish filled the air with scorpion bolts, but firing at a dragon is one thing, and killing it quite another. A few bolts glanced off the scales of the dragons, and one punched through Vhagar’s wing, but none of them found any vulnerable spots as the dragons swooped and banked and loosed great blasts of fire.

- Fire and Blood "The Long Reign - Jaehaerys and Alysanne: Policy, Progeny, and Pain"

When at last he had exhausted the hospitality of the westermen, he did not return to King’s Landing, but moved on directly to the Reach, flying Vermithor from Crakehall to Old Oak to begin a second progress even as the first was ending.

- Fire and Blood "The Long Reign - Jaehaerys and Alysanne: Policy, Progeny, and Pain"

Moreover, six other dragons made their lairs in the smoky caverns of the Dragonmont above the castle. There was Silverwing, Good Queen Alysanne’s mount of old; Seasmoke, the pale grey beast that had been the pride and passion of Ser Laenor Velaryon; hoary old Vermithor, unridden since the death of King Jaehaerys.

- Fire and Blood "The Dying of the Dragons: The Blacks and the Greens"