Game of Thrones: The White Dragon
Long ago, when the great Valyrian Freehold was still in infancy, the Ghiscari Empire attempted to destroy them before they became too great of a threat to their dominion over
the Known World. Four wars were waged between the Legions of the Harpy and the armies of the Dragonlords, and each time the Ghiscari lost and lost badly. The fifth time, the Dragonlords decided that enough was enough and laid waste to Old Ghis, the capital city of the Ghiscari. The walls and buildings were torn down, the land was burned and sown with salt, and all the survivors were put into slavery. Over time, save for a few minor colonies, all things Ghiscari disappeared from the Known World. In that last war, one Dragonlord made a name for himself. His name was Vaelon, his surname lost to history. He was credited with, before he turned twenty, slaying over a thousand warriors and the Last Ghiscari Emperor at the summit of the Great Pyramid while his dragon Meeranax set alight the pyramid's halls with dragonfire. After the war, he ruled as one of the richest and most powerful dragonlords in Valyria until his death at the age of ninety-one, outliving six of seven wives and thirty of forty children. One of his sons, Aelon, founded the peninsula's northern-most city of Targaryos and his descendants became known as the Targaryens.
They would preserve Valyria on the island outpost of Dragonstone after the Doom destroyed the Freehold, who would conquer the Seven Kingdoms of Westeros a century later and found a dynasty that would last three hundred years. And so, it seemed only fitting that the name of the most legendary of dragonlords be given to the son of Aerys of House Targaryen, the Second of his Name, King of the Andals, the First Men and the Rhoynar, Lord of the Seven Kingdoms and Protector of the Realm and his sister-wife, Queen Rhaella. The third-born, he was the twin brother of Viserys. Both he and his brother, many believed, would grow into fine young men would faithfully serve their older brother Prince Rhaegar as members of his Small Council or as knights of the Kingsguard. Sadly, fate had other plans.
By the time the twins were five, their father had all but lost his mind. Due to his madness, he saw knives in every shadow and treason on every face. He finally passed the point of no return when he burned alive Rickard Stark, Lord of Winterfell and Warden of the North, and forced his eldest son to strangle himself trying to save him. After that, the Houses of Arryn, Baratheon and Stark declared rebellion against the Iron Throne. With the death of Rhaegar at the Trident, the days of the Targaryen's were numbered. In the days following, there was chaos in the Red Keep. As the armies of the rebels marched on King's Landing, Aerys sent Viserys and Queen Rhaella to Dragonstone while Vaelon remained behind with Princess Elia Martell and her children Rhaenys and Aegon. Why he ordered this no one knows but when the host of Tywin Lannister sacked the city, Vaelon was the only Targaryen to survive the slaughter. Rescued by Varys, the Master of Whispers, found him and placed him in the custody of Ser Asher Stone, a bastard hedge knight of the Vale who had sworn himself to House Targaryen. Varys instructed him to ride south for Dorne and with the burning city on his heels Ser Asher raced out through the River Gate and disappeared into the Kingswood.
A fortnight later, he arrived in Dorne with his charge and begged Doran Martell, Lord of Sunspear and Prince of Dorne, for sanctuary for his charge and himself. Doran's brother Oberyn wanted justice for his murdered sister Elia and wanted the Dornish armies to march on King's Landing in Vaelon's name. But ten thousand Dornishmen had died at the Trident and Doran would see no more Dornish blood wasted. Instead, he welcomed the two exiles into his home. Ser Asher would become Sunspear's new master-at-arms and Prince Vaelon Targaryen would become Vorian Sand, the natural-born son of Ser Arthur Dayne. It was Doran's intention to hide Vaelon in plain sight while teaching him all the necessary skills needed to advise his brother and future King, Viserys, or become King himself. As the years passed he grew into a strong young man worthy of both his Targaryen heritage and the title of Prince, with a body built for war and a mind built for politics. And throughout all his lessons he had a mantra repeated over and over again by Oberyn, his favorite teacher: "Never forget the Lannisters."