I don't own any varieties of Pokemon or any varieties of Yu-Gi-Oh!
Crow is still investigating the underground tunnel and comes to the conclusion that it used to be the Ener-D reactor's research laboratory. He discovers a photograph of Yusei's family. At the Duel, Yusei draws a card; the Effect Monster, Zero Gardna. Goodwin notes that Yusei drew a Monster Card and activates the effect of "Destiny Activator", halving Yusei's Life Points to 50. Xx, Leo, Luna, and Trudge are worried for Yusei.
Roman says that Yusei's end is coming. Leo is worried sick for Yusei since he only has 50 Life Points left. Yusei says that his Life Points aren't gone yet. The three friends encourage Yusei. Yusei Summons "Zero Gardna" with 0 DEF. After that, he Sets a card and ends his turn. Roman is surprised that Yusei still has the will to fight and his will is just like Dr. Fudo's. He can't believe that, after seventeen years, the Signer to fight against him is Dr. Fudo's son and feels a strong sense of fate. Yusei replies that he doesn't have any fate with the likes of Roman. The Dark Signer reminds him that his Life Points are almost gone and that his soul will disappear into the light of Ener-D.
Roman decides to tell a story about Dr. Fudo to Yusei. He explains that, seventeen years ago, Dr. Fudo discovered the Planetary (Yusei) Particle. The twins wonder what Roman is talking about. Roman explains that the Planetary Particle, much like a planetary gear, binds particles together with other particles and that Dr. Fudo gave his son the name of his discovery. He also adds that Dr. Fudo wished that Yusei could be a person to connect people with each other through bonds. The Planetary Particle was a new, essential particle needed to create Ener-D. The doctor created his own theory and launched development on the non-polluting energy mechanism, the Ener-D Reactor. Rex and Roman were researchers but were impressed by the doctor's research and they were able to become his assistants. The doctor would talk about the possibilities of his research like a bright-eyed little boy. He believed in the world's future that the Ener-D Reactor could create. The research was still going well at that time.
As he tells the story, flashbacks of his life are shown. Dr. Fudo, Rex and Roman were researching until they felt a tremor. Roman saw the computer screen and says that the energy gauge showed abnormal figures, but the equipment seemed to be normal, though. They couldn't understand the problem, but back then, no one could think that the Ener-D Reactor would bring about something unprecedented. Because of the experiments, the city was struck by abnormal weather. Roman is shocked when Dr. Fudo says that the experiments must be stopped. Dr. Fudo says that it's out of hand. He doesn't know what it's due to, but he's positive that the abnormalities in the city are connected to the Ener-D Reactor. Rex was about to say that all the research will be lost. Dr. Fudo knows that already, but as long as their safety is being threatened, they can't continue to put the citizens in danger. Roman is a little saddened by that development.
Roman investigated every piece of data in the world and he found a location where disasters were occurring at the same time as the experiments, which was the Nazca Lines. He arrived in South America to investigate the Nazca Lines, having heard about the legend that there was a battle of the Gods 5000 years ago there. At the Nazca geoglyphs, he heard that evil beings were sealed inside and that they were locked in battle with the Crimson Dragon for supremacy of the world. During his investigation, he met a mysterious man who claimed to be from Iliaster. The man tells Roman it's a shame that the research on Ener-D would be halted. Roman wonders how the man knew about that, but the stranger simply replies asking whether Roman wishes to continue the research. He also adds that the research must continue, even if he has to get rid of Dr. Fudo.
Roman asks him what he is talking about. The stranger replies that in the light of Ener-D, there are possibilities that even Roman can't imagine and that the people of Iliaster believe that Roman is a true genius that should be in the first page of the history books. He also adds that Roman had already been chosen. Roman wonders what the stranger means by that. The stranger replies by pointing at the birthmark on Roman's left arm. He looks at his birthmark on his left arm and says that's a birthmark he has ever since he was born. The stranger says that fate has already chosen Roman and that he can't run away from that. Yusei is surprised that Roman revealed himself to be the fifth Signer.
Roman asks the stranger if the 5000 year old battle between the Gods actually existed and if it's going to happen again. The stranger simply replies that is something he should see with his very own eyes with the will of the light of Ener-D. After that, he laughs and disappears in a sandstorm. He returned in New Domino City and goes into the laboratory to see the Ener-D Reactor to search for truth in the stranger's claims. Suddenly, dark purple lights strike Roman's eyes and Roman sees visions about the Earthbound Immortals, the Crimson Dragon and their battle. The Ener-D Reactor was a device to resurrect the 5000 years old battle between the Gods. Crow continues his investigation of the old laboratory and find Rex in a research room, instantly recognizing him. He asks Rex why he is here. He replies that he came here to say goodbye to his big brother and he looks at the picture of him, Roman and Dr. Fudo. He says that his brother was considered a genius at a young age and he was proud of him. However, he took an unbelievable fate upon his shoulders.
While Rex is telling the story, flashbacks are shown. Dr. Fudo says that he's going to stop the Ener-D research, no matter what the agents say to him. One of the agents tells Dr. Fudo that he no longer has the authority to do that and has been relieved of his duties as a member of R.R.D. a while ago. Dr. Fudo cannot believe what he just heard. Another agent tells the doctor that they invested a lot in the development of Ener-D and that the successor has already been decided. The successor was revealed to be Roman.
Dr. Fudo asks Roman what is the meaning of this. Roman replies that Dr. Fudo doesn't have the courage to see the truth and tells Dr. Fudo that he shall fill that role himself. Dr. Fudo says that he already built control units for the Ener-D Reactor. When he says as long as Roman can't release the seals, Roman shows him the four cards: "Stardust Dragon", "Red Dragon Archfiend", "Black Rose Dragon" and "Ancient Fairy Dragon", which revealed to be the seals. Dr. Fudo takes the cards and the agents shoot at him with their ray guns. In his getaway, he drops one card, "Ancient Fairy Dragon". Rex finds Dr. Fudo badly wounded and tells him to hold on. Dr Fudo tells Rex to stop the Ener-D Reactor and gives him the three cards.
Rex searches for his brother in the laboratory. He finally finds his brother who just cut his left arm and put it in a container. Roman gives the container to his brother, saying that someday, the Signers will appear and no matter how many years it may take, Rex must gather them together and defeat Roman. Rex wonders what his brother is talking about, but Roman tells his brother to do what he says. He also adds that there are two Gods within his body, but he chose the path of darkness and tells his brother to take his left arm and get away from the laboratory, while a small amount of Roman's self remains. He holds his brother at gun point, forcing Rex to do what he says. He goes into the Ener-D Reactor Control Room and hits the self destruct button which causes the Zero Reverse, saying that this way, he'll be reborn as a Dark Signer. Before the explosion could kill him, Dr. Fudo put his son Yusei in a capsule escaping hatch, saving him from the explosion. The Zero Reverse has split the city into two.
Roman explains that back then, the Doors of the Netherworld began to open through the events of 5000 years ago. Crow concludes that, because of the accident, his parents, Yusei's parents and Jack's parents all died and the city was divided. Even the legendary man couldn't stop the city from dividing into two. Rex asks Crow if he knows the identity of the man who flew from Daedalus Bridge. Crow replies no, but couldn't forget about his wish to make Satellite and New Domino City into one someday. Rex says that Crow has the same aspirations as Yusei and asks the young man to send a message for him: That if he defeated his brother, he'll be waiting for him. After that, he goes into an elevator. Crow tries to stop him, wondering what he was talking about.
Yusei accuses Roman of trying to act like a God and asks how many lives does he have to take until he's satisfied. Roman tells Yusei that his fate was already in the hands of the Gods when he realized it and that he chose the darkness within his heart himself. He also adds that the world will be reborn soon. It's Roman's turn and he draws a card. He sends "Earthbound Immortal - Uru" to attack Yusei directly. Yusei activates the effect of "Zero Gardna", Tributing it to reduce the Battle Damage to zero. Roman is impressed that Yusei managed to seal off his attack. He Sets a card and ends his turn. Leo says that if Yusei takes another attack, he'll lose the Duel. Trudge tells Leo to believe in Yusei.
It's Yusei's turn and he draws a card. He Sets two cards, wonders what will Roman do next and ends his turn. Trudge thinks that Yusei is depending on that 's Roman's turn and he draws a card. The card he draws is the Spell Card, "Earthbound Whirlwind". He activates it, letting him destroy all Spell and Trap Cards on the field since he controls an "Earthbound Immortal". Trudge says that if Yusei's two face-down cards are destroyed, he'll be completely exposed .This is what Yusei has been waiting for. He activates the Trap Card, "Starlight Road", negating an effect that destroys two or more cards. "Earthbound Whirlwind" is destroyed. Also, it allows Yusei to Special Summon "Stardust Dragon", which appears with 2500 ATK. Leo is happy that Yusei stopped the opponent's move and Summoned "Stardust Dragon". Roman says that despite the white dragon's arrival, it's too late. Yusei replies it's never too late, which confuses Roman. Yusei activates the Trap Card, "Shooting Star" ,allowing him to destroy one card when he has a "Stardust Dragon" on his field. The card he chose to destroy is the Field Spell Card, "Spider Web". Roman says that it's too late and activates the Trap Card, "Anti Emptiness", thus making the ATK "Uru" zero for the turn to negate the activation of a Spell or Trap. Roman ends his turn and the ATK of "Uru" goes back to 3000.
It's Yusei's turn and he draws a card. He activates the Spell Card, "Battle Waltz", Summoning a "Waltz Token" that copies a Synchro Monster except for its effect. A "Waltz Token" appears with the same ATK as "Stardust Dragon". Roman reminds Yusei that "Earthbound Immortals" can't be chosen as an attack target. But Yusei tells Roman that he's the target he's aiming at. He sends his "Waltz Token" to attack Roman directly, but Roman activates "Roar of the Earthbound". When a monster with lower ATK than Uru attacks, it destroys the attacking monster and deals half the monster's ATK as damage to the opposing player. Yusei activates the effect of "Stardust Dragon", Tributing it and negating a card destroying effect. "Roar of the Earthbound" is destroyed and "Waltz Token" goes straight to Roman. Luna thinks that Yusei will win. But Roman activates the Trap Card, "Brilliant Shrine Art", redirecting the attack to "Uru". Roman tells Yusei that's the end, but he must not feel bad, because they have inscribed a glorious page in this world's history. Roman thought he had won the Duel, but notices that Yusei's Life Points haven't dropped. Yusei tells him that when a "Waltz Token" is destroyed, both players take 0 Battle Damage. He also activates the token's effect. A monster that destroys the token loses ATK equal to the token's ATK. Uru's ATK goes to 500.
Yusei tells Roman that he doesn't care about fate and that because of it, there have been so many victims. He also adds that Roman has forgotten what the people who survived are going through and that if his father hadn't conducted his experiments, the incident seventeen years ago would never have occurred. Yusei reminds Roman that the experiment took the lives of both Crow and Jack's parents - that it ruined everyone's lives. If it had never happened, everyone would have had loving parents and happy lives. He asks with tears why they look at him as a friend, why they don't bear any bad feelings and support him - what is he supposed to do? How is he supposed to tell them that he's sorry? Trudge, Leo and Luna are overwhelmed by Yusei's words. Yusei dares Roman to give him an answer. Roman wonders if that is the darkness within Yusei's heart. Yusei then hears Crow's voice, saying he'll give him his answer. He sees Crow below him. Crow apologizes to Yusei, saying that despite being his friend, he has never noticed the feelings Yusei has been shouldering. Crow then tells Yusei that he has never thought that his life was ruined because of Yusei or his father, which is why Yusei doesn't have to feel responsible for the incident. Crow adds that if he has a fate, it was only having met Yusei, Jack and many other friends. He encourages Yusei to win the Duel for their sake too. Yusei is touched by Crow's word and decides to continue the duel. He tells Roman that the one illuminating his heart isn't the Ener-D's light, but his irreplaceable friends and that this duel is his final hope. He activates the Trap Card, "Stardust Flash". During the turn "Stardust Dragon" Tributed itself, it Special Summons a "Stardust Dragon" from his Graveyard. Roman is shocked by the return of the white dragon. Yusei sends "Stardust Dragon" to attack and destroy Uru. Roman loses the rest of his Life Points and Yusei wins the Duel.
Despite his defeat, Roman laughs, which surprises Yusei. Roman tells Yusei that this isn't the end and that an ultimate god has already been unleashed. While explaining this, he turns slowly into dust. He also adds that if all four units are not controlled before sunset, the King of the Netherworld will be revived. He removes the Duel Disk from his wrist. Yusei is shocked by Roman's revelation. Roman tells Yusei he won't allow him to leave this place and pulls a switch on his mechanical left arm, which allows him to pull it off. It causes the bridge to explode and Yusei falls from the bridge into the Ener-D's light. Crow, Leo, Luna and Trudge can't do anything but watch their friend plummet. Outside Satellite, Rex returns to his mansion, goes into the temple and looks at the container that contains Roman's left arm with the head of the Crimson Dragon on it.