Feolthanos Feolthanos the Eternal is the main antagonist of " " . The self proclaimed God of the aegyl , he has been alive for a long time , thanks to the auracite . With the barrier around Lemurés gone , he plots to get revenge on Ivalice . This vengeance is prompted by the Occuria , who tried to dominate the aegyl , prompting Feolthanos to take them to Lemurés . Story . Exodus to the Skies . Long ago , Feolthanos led the aegyl . During his rule he took a viera wife and had children who would become the feol viera , named after him . He revolted against the Occuria and took his people to Lemurés , using the auraliths to lock Lemurés away in Mist , evading the Occuria while trapping himself and his people inside . Before doing it , Feolthanos left behind treasures for his viera children in the form of some auracite and a giant airship hoping they would reach him some day in Lemurés . The airship houses a piece of Feolthanos ' s own anima , giving it a degree of autonomy . When his people took flight and settled in the sky continent Feolthanos wrote " The Canon " , a book of verse laying down the foundations and principles for the new aegyl community . Though his people had found a new home , Feolthanos harbored a vengeance against the Occuria . He used the auracite to build a palace high in the sky , even above the Purvama , where he absorbed the auracites ' power , melding with the auralith in his palace to become a god himself . He used the two other auraliths to steal the anima of the rest of the aegyl to prevent disputes and make them easier to control , but Feolthanos could not extend his grip to the land of Ivalice due to the barrier placed by the Occuria . Centuries later , thanks to the Mist Dr . Cid released from the Sun - Cryst , the barrier around Lemurés faded , and Feolthanos could begin his revenge on the land from which his people had been exiled so long ago . Possessing the young feol viera Mydia , Feolthanos turned her into the Judge of Wings , an embodiment of his anger and hatred . It was because of the recent loss of her love Velis and being a feol viera that made her the best candidate for possession . Crusade . Using Mydia , Feolthanos gathers auracite from the main islands of Lemurés to give to greedy sky pirates and use their anima to grow stronger , but the young sky pirate Vaan and his friends interfere . After meeting Velis on the jungle island of Tswarra , the sky pirates realize the Judge of Wings is but a pawn to a higher power . When Ashe and Basch join Vaan ' s team they explore Ivalice for clues and uncover a relic in the Glabados Ruins that explains Feolthanos ' s past and motives . Venturing to the Feol Warren , they find and fight a sorrowful and murderous Mydia who had completed killing off the last of her race . When Mydia herself is defeated , her cold and manipulative shell melts away allowing her to break free of the chains placed on her . The damage to her body is too great , and Mydia asks the sky pirates to defeat Feolthanos as she passes away . By following Eternity ' s March , Vaan and his friends reach the Keep of Forgotten Time , Feolthanos ' s fortress high in the sky . They battle an army of illusionary aegyl and an illusionary Feolthanos , and discover his true nature as the last auralith . The auracite grants him incredible summoning powers , but the sky pirates overcome the summoned Yarhi and plead with Feolthanos to stop his tyranny . Their intentions are for naught , and Feolthanos summons a cloned Mydia for them to battle . Feolthanos has absorbed too much spiritual power the room collapses , sending the party fleeing . Fall from Glory . A portal to the Womb of Feolthanos opens and the party travels into a maze of Feolthanos ' s dreams and soul , battling ancient aegyl along the way . They find Feolthanos , now a giant demonic Yarhi called Feolthanos Exultant , and defeat him . The powers Feolthanos had drained from the aegyl fade away . Back in Feolthanos ' s throne room , Vaan finds himself alone , and Feolthanos appears on his throne . Even though he has lost the power of the anima , Feolthanos still nearly kills Vaan , but his friends arrive and together they defeat the misguided aegyl . Realizing what he has done , Feolthanos allows himself to fade away . With him gone , Lemurés crumbles and falls from the sky , and the " Galbana " flies away to places unknown . Gameplay . Feolthanos is fought as the final boss . Other appearances . " Final Fantasy Trading Card Game " . Feolthanos appears with a fire - elemental card . His boss form has a dark - elemental card . Etymology . This would be symbolic of Feolthanos ' s use of the auracite to control the Yarhi as his servants . It is likely that " thanos " is a reference to the Greek word " thanatos " .