Vhagar was the mount of Queen Visenya Targaryen through the Conquest, and the bronze-and-green sister to her brother's Balerion. She fought on the Field of Fire with Meraxes, and for sixty years after the wars carried Visenya, the dread of every man who saw her shadow on the ground.
After Visenya's death Vhagar passed to a string of Targaryen princes, growing larger with every passing year. By the time she came to Prince Aemond (claimed by him at Driftmark in the wake of Laena Velaryon's death), Vhagar was the largest dragon living, second in all history only to Balerion. In 130 AC she met Caraxes above the Gods Eye in the great battle of the Dance, and there both dragons fell. Aemond fell with her.