Aporia

Aporia is the true and combined form of the Three Emperors of Yliaster, Jakob, Primo and Lester. Each one of them is a different part of his lifetime: Lester being his childhood, Primo in his early midlife, and Jakob his older days. Aporia comes from an apocalyptic future world, which he sees as a failure by humans, and is determined to change history, to protect the world and to ensure it will never be destroyed by humanity's errors.

In the beginning Aporia fought Team 5D's stating that himself was en embodiment of despair because of what it had suffered in the future. However after fighting so many times against the Signers, Aporia's personality changes stating that the true reason he had continue to live even after suffering, was that because himself never lost hope, believing that it could be found within the depth of despair.

Childhood
As the world was evolving at an ever-increasing rate, and the human race became dependent on the Ener-D system, and Synchro Summons, which were the gears that accelerated the spin of the Ener-D system. The Ener-D system began to spin faster and faster, and eventually, the speed became uncontrollable.

At the same time, an invasion of Machine Emperors were set upon the world, and the world was sent to ruin after the invasion. All life forms in the world had been vanquished, by the subsequent Machine Emperor invasion.

As a child, Aporia, along with his mother and father, was chased by a Machine Emperor Grannel Infinity. The Machine Emperor fired a beam at them, killing his parents. He regarded the loss of the people that loved him as one of three major despairs in his life. His hair went prematurely gray sometime after this point but before his early teenage years.

Adulthood
At some point in his life, Aporia met and fell in love with a fellow freedom fighter, whom he fought the Machine Emperors with.

They later attempt to ambush a Machine Emperor Grannel together using rocket launchers. However, the Machine Emperor retaliates by blowing up half the building they were shooting from, taking Aporia's lover with it. Aporia regarded the loss of the one he loved as the second of three major despairs in his life.

Old age
The Ener-D eventually changed and spun in the opposite direction, sparking a global disaster. In his old age, Aporia found himself alone. He initially believed himself to be the only survivor and regarded having no one left to love as the third of three major despairs of his life.

Aporia soon found he wasn't the only survivor as he met Antinomy, Paradox and ZONE. Being the last survivors of this world, the four of them believed it to be their mission to create a better future.

They tried to dispose of the core power of Ener-D, which wiped out the world before. They performed countless experiments to try and find a solution to restore the world to the way it once was. However eventually ZONE had become more mechanical and Antinomy and Paradox died. Aporia considered himself to be the only one left alive.

As Aporia was about to die, he placed himself in a capsule. He asked ZONE to do whatever it took to prevent their future from ever occurring, and insisted that ZONE split him into three embodiments based on the three despairs of his life. ZONE promised that he would.

Embodiments of despair
Keeping his word, ZONE split Aporia's being into three android-like embodiments of despair, Lester, Primo and Jakob, who were sent back in time. The three of them became the Three Emperors of Yliaster and used their power of falsification of history to alter the current events in time, including having themselves enrolled into the World Racing Grand Prix as Team New World. . Team New World faced Team 5D's in the final event of the tournament. When both teams were down to their last duelist, Yusei Fudo destroyed Jakob's "Machine Emperor Grannel Infinity" with "Shooting Star Dragon". The three embodiments then combined back into Aporia again.

World Racing Grand Prix final
Aporia took over Yusei and Jakob's Duel and proceeded to Summon his "Machine Imperial God Machinicle Infinity", overwhelming Yusei and putting him at a severe disadvantage. Aporia showed Team 5D's the future world from which he had came from and explained that he was going to remove New Domino City from history to prevent it from happening. However Yusei refused to believe that humans were the reason that the future world had been destroyed, and continued to fight on. Yusei managed to Summon "Red Nova Dragon", "Black-Winged Dragon" and "Shooting Star Dragon" and use them to defeat Aporia. Contrary to what Aporia had expected, the Grand Design was completed despite his loss and the Ark Cradle began to descend on New Domino.

ZONE managed to recover Aporia's mechanical body and took it to the Ark Cradle, where his human body still resided. ZONE informed him of the Ark Cradle's appearance over New Domino despite the loss. ZONE explained that an outside interference has caused the future to change. ZONE asked if Aporia was willing to try to change the future again, only for him to respond that he would do anything. Aporia felt much obliged, as he regarded ZONE as his eternal friend. Tools then began to repair Aporia's mechanical body.

Ark Cradle
With his repairs fully competed, Aporia nows stands protecting the second Gear where he is challenged by Jack, Leo, and Luna. In a 3-on-1 duel, they are forcibly equipped with machines that inflict real damage. After summoning Machine Imperial God Dragon Asterisk and his Machine Imperial Soldiers and finally by activating several Burning cards, Aporia reduces Jack and Luna's life points to 700 and 100 respectively. Leo begins crying Aporia simply ends his turn after explaining to Leo that what he is feeling is true despair. However, Jack shows Leo how to never give into despair and keep believing in hope. After doing so, Jack's life points are reduced to 100, but Leo begins acting as Jack and Luna's shield. Leo ends up dying from the damage, but Ancient Fairy Dragon explains that she needs him to protect Luna and revives him through the effect of Morphtronic Lighton. Leo is then revived as a Signer, and Aporia watches helplessly as Leo summons Life Stream Dragon. Through Life Stream Dragon's effect, Luna, Jack and Leo's life points become 2000. Life Stream Dragon's second effect negates effect damage, thus negating Asterisk's burn effect.

Leo attacks but Aporia sends Skiel Ein to the Graveyard in order to protect Asterisk through its own effect. Luna then destroys Fortissimo through Ancient Fairy Dragon's effect and gains 1000 life points. Luna activates her own Field Spell and then Jack manages to summon Red Nova Dragon. Aporia activates his own trap and summons both Skiel Ein and his Machine Imperial God Machinicle Infinity thus Asterisk's attack becomes 8300. However, both Leo and Luna activate their trap cards and reduce its attack, causing Jack's Red Nova Dragon's attack to be higher. When Aporia realizes he is about to lose, he wonders if it's because he feels despair. Jack explains to him that fighting to protect ZONE makes Aporia feel hope, not despair. Jack's attack reduces Aporia's life to 0. As the field surrounding them collapses, Jack, Leo and Luna escape. Aporia then begins falling to his "death", with a smile on his face and notes that he feels no pain, only hope.

However, he later reappears at the center gear to Team 5D's showing he had survived the fall and challenges Z-one in an effort to show him there is still hope in the future. Before the duels begins, Aporia reveals to Leo that witnessing the hope the Signer had on their duel, made him realized the bonds within Team 5D's, as well as Leo's own personal growth, is the same hope Aporia himself had been searching for so long. That same hope being the reason he will fight against Z-one. However, he is finally outsmarted by Z-one. Ironically, he is defeated when the card he draws is not After Glow, as he'd hoped, but Machine Emperor Grannel Infinity, the very creature who killed his parents and lover in his previous life. Before he dies, however, he fuses his duel disk with Yusei's Duel Runner, giving it the power to fly, for the final Duel between Yusei and Z-one.

Abilities
It is highly notable that that Aporia's body is an android much like his counterparts with the qualities of the real person. Just like Jakob, and Primo, Aporia can fuse with his Duel Runner, and is the one with the most connections to it. He can even use the ring fused to his back as his duel disk much like Lester. Aporia can also combine with his Field Spell Fortissimo the Moving Fortress in the same manner.

Aporia is later shown to be telepathic, following his conversation with ZONE after being brough aboard the Ark Cradle. In episode 147 he was able to fuse his duel disk with yusei go, giving it the power to fly

Etymology
The name "Aporia" comes from the Greek word "ἀπορία", which literally means question or wonder and is used in philosophy to refer to a philosophical puzzle or state of puzzlement, and, in rhetoric, a rhetorically useful expression of doubt. It may also derive from another Greek word "απόρροια", which literally means result.

Ground
Aporia's Ground Deck is a Machine Emperor-themed Burn Deck which focuses on dealing effect damage to the opponent via his field spell Fortissimo the Moving Fortress as well as the additional cards to his field spell such as Level Cannon and Lock-On Laser. He utilizes cards such as Damage Boost to punish anti-Burning severely. His ground deck also focuses on swarming the field with Machine Imperial Soldiers which are based on his embodiments' Machine Emperors and summoning his ace monster Machine Imperial God Dragon Asterisk.

During his duel with ZONE, Aporia uses his Machine Emperor cards for swarming the field.

Turbo Deck
Aporia's Turbo Deck is a hybrid of the Machine Emperor cards used by his embodiments, with the Machine Imperial God Machinicle Infinity as its centerpiece. He also uses cards designed at countering any attempt at escaping his Machine Emperors' Synchro-stealing effect. The majority of Aporia's victories were done through his embodiments.