Vermax

"But the foolish boy had Vermax hooked like a trout and dragged into the sea, where he soaked up even more arrows than sea-water."

- - Viserys II Targaryen Meleys was one of the dragons that belonged to House Targaryen, which fought during the great civil war known as the Dance of the Dragons, during which it was the mount of Rhaenyra Targaryen's eldest son Jacaerys Velaryon.

Biography
Vermax was one of the twelve dragons, on the island of Dragonstone and one of the six who had a rider. Vermax's was Prince Jacaerys Velaryon. During the House Targaryen civil war, known as the Dance of the Dragons, on Rhaenyra Targaryen's orders, he flew the young prince to the Vale of Arryn and The North, in order to recruit supporters for Rhaenyra's faction, the Blacks. He was successful. After Aegon III Targaryen and Viserys II Targaryen, were ambushed by Greens on the way to Essos, only Aegon returned and Viserys was captured by the enemy. Jacaerys vowed to rescue his younger brother, taking his dragon, to the enemy fleet. However, the Green archers shot Vermax numerous times until, he fell into the water below. The archers continued to shoot at both Vermax and Jacaerys until they died beneath the water.

Dragon Egg
When Prince Jacaerys Velaryon was young, there were rumours that he was a bastard, fathered by Ser Harwin Strong, instead of his mother Rhaenyra Targaryen's husband, Ser Laenor Velaryon. The rumours were spread by Queen Alicent Hightower and her followers at court. Those who doubted the paternity of Jacaerys and his brothers also doubted that the dragon eggs the boys had been given would ever hatch, but they were quickly disappointed, as each of the eggs soon hatched in turn. The hatchling that bonded with Prince Jacaerys was Vermax.

Dance of the Dragons
By the time the Dance of the Dragons began, Vermax was big enough to ride. Prince Jacaerys flew north on his back, as a messenger for his mother, Queen Rhaenyra Targaryen, to treat with Lady Jeyne Arryn, Lord Manderly, and Lord Cregan Stark. The mission was a success.The Testimony of Mushroom claims that Vermax laid a clutch of eggs in the depths of the crypts of Winterfell, but this tale is most likely false.

Prince Jacaerys used Vermax in battle, during the Battle in the Gullet. There, Vermax attacked a fleet, but he flew too low and went crashing down into the sea. Differing tales are told of how and why the dragon fell. Jacaerys also perished.