Arrax

Arrax belonged to Lucerys Velaryon, second son of Rhaenyra Targaryen and by most reckonings the gentlest of her children — a boy more suited to a maester's books than a dragon's saddle, thrust into the war regardless as its youngest working envoy. When Rhaenyra needed Storm's End's support against the greens, it was Lucerys and Arrax she sent to plead for it, a mission of diplomacy rather than war undertaken on a dragon barely old enough to be called grown. He found Storm's End already claimed by a rival embassy — his uncle Aemond Targaryen, arrived first on Vhagar to court Lord Borros Baratheon's daughters for his own household, and by extension the storm lords' swords for the greens.

The two princes traded words rather than blows inside the castle, by every surviving account, and Lucerys left first, hoping to outrun the confrontation entirely. He did not manage it. Aemond followed him up on Vhagar, and whether by command or by an old dragon's hunting instinct outrunning her rider's restraint — the histories decline to settle the question — Vhagar ran Arrax down in the storm and tore him apart in the air, Lucerys falling with him into the sea below. It was the first dragon death of the war and the first royal death besides, and it made the peace both sides had been pretending to want impossible: within the same moon, the vengeance killing remembered as Blood and Cheese answered a nephew's death with a nephew's death, and there was no calling either back.