- "Don't forget the prophet Lodos, who claimed who promised that the Drowned God would rise up and destroy Aegon the Conqueror!"
After the burning of Harrenhal and the resulting extinction of House Hoare, Lodos, a Drowned Man declared that he had visions of Aegon the Conqueror's fleet being destroyed by krakens. When Aegon did come to invade the Iron Islands, the prophesied krakens did not arrive, so Lodos, with stones in his pockets, went out to speak with the Drowned God. Thousands of people followed him into the sea, and their bodies washed ashore the Iron Islands for years to come.
Lodos is mentioned by the archmaesters of the Citadel as they discuss a raven they receive from Bran Stark, warning the the Night King and his army are marching on Eastwatch-by-the-Sea. One of them compares his claim that he saw this through warging to Lodos's claim that about the Drowned God destroying Aegon the Conqueror.
In the books
In The World of Ice and Fire, Lodos was a Drowned Man who claimed to be the living son of the Drowned God. He was crowned King of the Iron Islands by Nagga's bones at Old Wyk following the death of Harren the Black at the Burning of Harrenhal during the Targaryen Conquest.
With the extinction of House Hoare, and all of the ironborn's strength on the mainland destroyed, they fell into infighting on their home islands. With no clear successor, five separate men on five different islands declared themselves king, among them Lodos, who was crowned by a gathering of forty other priests.
When Aegon I Targaryen finally attacked the Iron Islands four years later, with a vast armada and his dragons, Lodos called upon the Drowned God to send krakens to drag Aegon's fleet into the depths of the sea. When no krakens appeared, Lodos filled his robes with stones and walked into the sea to "take council" with the Drowned God. Thousands followed him and their corpses washed up on the shores for years to come, though Lodos's body was never found.