Thordak self-titled The Cinder King was an ancient red dragon, even larger than most other ancient dragons. He and Raishan made the deal to form the Chroma Conclave. With time, Thordak went mad, presumably due to the heart crystal (used to bind him to the Elemental Plane of Fire that was embedded in his chest. Notably, Thordak killed Elaina (the mother of Vax'ildan and Vex'ahlia.