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Duke Pantarei is the hidden main antagonist in Tales of Vesperia. Once a renowned hero from The Great War, he began to resent humanity when his friend, an Entelexeia named Elucifur, was sacrificed for the sake of the future of humans. What's more, he found out that the Ancients had tried to destroy the Entelexeia in times past because they thought of them as enemies of the blastia, the technology used to convert aer into energy and grant people a better lifestyle. They didn't realize all the Entelexeia wanted was to restore the balance of aer to avoid a cataclysm called the Adephagos that would manifest. Fed up with the mistreating of the creatures, Duke tried to wipe humanity from the planet as he felt it would account for a better future.
Duke is the wielder of the arcane sword, "Dein Nomos", stolen from the Empire and even entrusting him to Yuri Lowell in hopes that he would help him create a better world. Their understanding of this concept, however, is not the same and he reclaims it shortly after. During the game's final battle in Tarqaron, Duke's domination of the sword is total and is able to control it telepathically.
Before the events of the story, Duke was an important figure in the Great War, in which humans and the Entelexeia fought. He fought alongside the Entelexeia Elucifur so that humans and the Entelexeia could live in peace. Although they were victorious, some humans no longer trusted the Entelexeia and executed Elucifur. After this betrayal, Duke lost all faith in humanity and cut all ties with them. He only appeared when he felt it was necessary for the protection of the world and the Entelexeia.
Role in the Plot
Duke wields the lost sword Dein Nomos, which is able to control the flow of aer, and is proof of imperial lineage. Later in the story, he hands this sword over to Yuri Lowell in hopes that he will fight for identical goals. However, Duke eventually feels their goals do not coincide and reclaims the sword. This change of heart occurs when the barrier of Zaude is destroyed and the Adephagos once again threatens the world. Duke then resurrects Tarqaron with the intention of trading all human life, including himself, for the destruction of the Adephagos. Yuri and his companions resolve to put a stop to his plans by offering all the blastia in place of humanity. Duke, however, longs to return the world to the rule of the Entelexeia as recompense for the slaughter of Elucifer, and fights against Yuri and his companions, serving as the story's "final boss". After Yuri and his companions prove victorious, Duke is finally persuaded by their perseverance and assists them through the aid of Dein Nomos, destroying the Adephagos.