The demon Tyranthraxus, also known as the Lord of the Ruins or the Great Possessor, ruled over Ruined Phlan from 1306 to 1340 DR, possessing the body of the corrupted bronze dragon Srossar, and utilising the power of the Pool of Radiance. His lair was beneath Valjevo Castle. In 1340 DR he was defeated by Ren o' the Blade and a party of adventurers.