Its my theory that all the destroyed or ended civilizations were reborn on Etherys. The dragons are here, omega and alpha are the omicrons.... the namazu are clearly the civilization that died by poison in the 90 dungeon (their bodies match exactly under the diving suits). Garleans could be the 2nd area war civilization. I havent quite placed the Ea or the 3rd dungeon people but im sure ill theory it eventually