"A Vicious Cycle", known as "The Eternal Duel" in the Japanese version, is the ninety-ninth episode of the Yu-Gi-Oh! ARC-V anime. It first aired in Japan as a one hour special with episode 100 on April 3, 2016 and in Australia on December 2, 2016.
Declan and Roget begin their Duel with their pride on the line! Despite Declan's marvelous display of his "D/D" Deck, Roget manages to counter his strategies. However, something unexpected happens to Roget's appearance. Meanwhile, Yuya, Jack and the Lancers reach the Sector Security building, where Declan is.
Sylvio and Gong run through the streets towards the smoking Sector Security Headquarters and Sylvio begs Gong to wait up, protesting that Gong is running too quickly for someone who is wearing metal sandals. Gong snaps that his friends and comrades are in danger; he can't just wait. They hear a bird's cry and stop and see Shay flying overhead on "Raidraptor - Rise Falcon", and Sylvio angrily asks why Shay can't give them a ride. The High Council's helicopter lands outside the Sector Security Headquarters and Yuya leaps out. Jack and Crow drive past on their Duel Runners and Jack tells Crow, "Let's go!" Crow agrees, and they both crash through the glass of the windows. Up above, Shay orders "Rise Falcon" to attack and "Rise Falcon" destroys a window with a sonic scream. "Rise Falcon" swoops into the building and Shay leaps from his monster and runs into the building.
Declan and Roget face off. Declan reiterates that Roget equipped a monster already unaffected by card effects with an Equip Spell Card to prevent it from being destroyed in battle. Roget reminds him that it also has the ability to inflict 1000 damage during each of his turns for each Spell Card he controls and he calls it a truly impenetrable combo. No matter who they are they cannot defeat this. Declan adjusts his glasses and he warns Roget that there are no absolutes in either business or Dueling. No matter how carefully one prepares for risks there is a gap in every plan. "A gap?" Roget asks. Declan explains that it is the duty of the elite to find and exploit that gap, and he declares his turn and he draws. He activates the Continuous Spell Card, "Forbidden Dark Contract with the Swamp King", which allows him to Special Summon the Level 7 "D/D/D Chaos King Apocalypse" from his hand with its effect negated. Roget observes that Declan also has a Pendulum Monster. Declan then explains that he can then use the Special Summoned monster as a Fusion Material to perform a Fusion Summon. He fuses "Apocalypse" with the "D/D Lamia" in his hand, and he chants "Chaotic king who watches over the world's fate. Drink the blood washed away by time and become a dragon-slaying hero! Fusion Summon! Be born! Level 8! D/D/D Dragonbane King Beowulf!" Roget comments that it's as expected of the Professor's son to perform a Fusion Summon without a Fusion Spell. Declan then activates the effect of "D/D Lamia" from his Graveyard, allowing him to send a "Dark Contract" to the Graveyard and Special Summon it. Sending "Forbidden Dark Contract with the Swamp King" to the Graveyard, he Special Summons the Tuner monster. Roget is shocked to learn that Declan has a Tuner monster, and he realizes that Declan can also Synchro Summon. Declan replies that of course he can; he has mastery of all Summoning methods after all.
Yuya, Jack and Crow run through the corridors, Yuya calling Zuzu's name.
Declan uses the Scale 6 "D/D Savant Thomas" and the Scale 8 "D/D Savant Nikola" to Set the Pendulum Scale, allowing him to simultaneously Summon Level 7 monsters. He chants, "Grand power that shakes my very soul, arise within me and give birth to a new light that rends the darkness. Pendulum Summon! Be reborn from my Extra Deck! D/D/D Chaos King Apocalypse!" Then Declan tunes the Level 7 "Apocalypse" with the Level 1 "D/D Lamia" and he chants, "Climb over the corpses of heroes, carrying your bloodstained blade! Synchro Summon! Be born! Level 8! D/D/D Cursed King Siegfried!" Roget is shocked that Declan can also perform a Pendulum-Synchro Summon.
Declan activates the effect of "Siegfried", allowing him to negate the effect of a face-up Spell or Trap Card until the next Standby Phase. He chooses "Ancient Gear Magic Shield" and "Siegfried" fires a beam of red light from its forehead, striking the shield and dissipating the energy. The DEF of "Gear Devil" returns to 1800, much to Roget's shock. Declan declares his Battle Phase, attacking "Gear Devil" with "Beowulf". As "Beowulf" rampages forwards and glows with lightning, Declan explains that the attack of "Beowulf" will inflict piercing battle damage. "Beowulf" destroys "Gear Devil", reducing Roget to 2800 LP. Declan declares the finishing blow and he attacks directly with "Siegfried". "Siegfried" charges and reduces Roget's LP to zero with one swipe of its greatsword. Roget screams as the force flings him back into the wall and shocks him with electricity – and vanishes.
Declan flinches in shock. But then Roget appears again, and he tells Declan that it won't end, this Duel will never end. Outside the room Riley has just been informed by Moon Shadow that Roget is immortal. Moon explains that he and Sora Dueled Roget. Sora defeated him with an attack from "Frightfur Bear", flinging Roget into the wall of the corridor, which shimmered with the same light as the room that Declan and Roget are currently Dueling in. Roget had vanished, much to Sora's shock, and Moon had tried to look for Zuzu. But Roget had reappeared with a fresh five cards in his hand and his body crackled with lightning; his Duel Disk declaring "Intrusion Penalty: 2000 LP" and reducing him to 2000 LP. Roget's laughing continues in the present, while Declan takes note of the intrusion penalty, realizing that this is a different Roget from before. Roget agrees, but he claims that this does not change the fact that he is himself; Jean-Michel Roget. That is why Roget will not lose; even if he is defeated time and time again, he will revive like a phoenix, until Declan is worn, beaten, and crying that he cannot fight anymore. He bursts out laughing while Declan remains silent.
Sylvio and Gong arrive at Roget's office and Sylvio is shocked by the devastation. Gong muses that Sora broadcasted his message from here and Sylvio asks if Sora got caught up in the explosion. Shay states that something like this will not kill Sora. He will not die until he completes his mission; Sora Perse is one with such tenacity. Outside the room where the Duel is taking place, Moon attempts to use his stolen ID to open the door, but all he gets is an error message. He laments that he can do nothing about the lock. Yuya, Jack and Crow run around the corner, Yuya calling Riley and Moon's names. Riley responds in kind, and Yuya asks where Zuzu is. Riley explains that Declan is Dueling Roget in order to get her back.
Declan activates the Pendulum Effect of "Thomas", allowing him to return a "D/D" Pendulum Monster from his Extra Deck to his hand. He returns "Apocalypse" to his hand and then he Sets a card to end his turn. Roget confirms that the Duel will continue until Declan surrenders and he excitedly suggests that they enjoy themselves before laughing. Outside, Crow curses; their enemy is right in front of them and they can't do anything. Gong, Shay and Sylvio race up, Gong calling Yuya's name. Yuya quickly explains that Zuzu is in the nest room and that Declan is Dueling Roget in order to get her back, but the door is locked. Sora's voice interrupts, claiming that he can open the lock for Yuya. Yuya gasps Sora's name and Sora apologizes for losing Celina and Zuzu. He falls forwards when he tries to take a step and Yuya catches him, telling Sora not to force himself. Sora thanks Yuya and he tells him to leave it to him; he will open that lock for Yuya. Off to the side, Jack looks at Crow and they exchange nods. Sora activates a "Hacking mode" of his Duel Disk while Yuya holds him up, and he begins entering commands.
The door opens and the Lancers run in, with Gong carrying Sora. Yuya cries Zuzu's name and Riley cries Declan's, but Declan throws out his arm and wards them back. He muses on the idea of an eternal Duel and deems it interesting. Yuya asks, "eternally?" and Roget confirms that he will never lose. "If it can continue eternally, that is", Declan notes. He warns Roget that he will eventually surrender before him. Roget incredulously asks if Declan really thinks that he will surrender to him, and he asks what nonsense Declan is spewing. He declares his turn and draws. Declan immediately Special Summons "Apocalypse" from his hand via its own effect, and then the effect of "Apocalypse" destroys "Thomas" and "Nikola" in his Pendulum Zones. Roget is shocked and Declan clarifies that he can only activate this effect once per turn, and only during his opponent's turn. Roget asks if Pendulum was the weapon of the Lancers and he asks if Declan has gone mad for abandoning them. Declan retorts that he has not abandoned them and he activates the effect of "Nikola" since it was destroyed and sent to the Extra Deck, allowing him to return a "D/D/D" Pendulum Monster he controls to his hand and re-Set "Nikola" and "Thomas" in his Pendulum Zones. Then he activates the Continuous Trap Card "Dark Contract with the Swinging Abyss", allowing him to inflict the DEF of "D/D" Pendulum Monsters that return to his hand to Roget. "Apocalypse" has 2000 DEF, and it blasts twin serrated disks from its back that crash into Roget and reduce his LP to zero. Roget is flung into the wall and he vanishes again. Gong gasps that Roget vanished, but Moon warns them that he'll reappear again. And sure enough, Roget rematerializes and he derides Declan's attempts as pointless. Sylvio and Yuya are shocked and Sylvio gasps that Roget is back again as Roget steps forwards and takes the intrusion penalty, reducing him to 2000 LP. Roget declares that no matter how many times they defeat him he will be revived.
"Yes and the same thing will repeat over and over again," Declan explains. Roget asks, "What?" and Declan clarifies that he will Special Summon "Apocalypse" from his hand and destroy "Nikola" and "Thomas" in the Pendulum Zones. But then he'll use the effect of "Nikola" to return "Apocalypse" to his hand and return "Nikola" and "Thomas" to the Pendulum Zones, thus inflicting the 2000 DEF of "Apocalypse" to Roget and defeating him. And since Roget will always have 2000 LP as a result of the intrusion penalty, he'll continue to be defeated eternally. Roget gasps in shock, and Declan asks Roget to tell him what his plan is now. He looks up, as do everyone else, to see a gap in the shimmering walls where the real Roget is Dueling with a visor over his eyes and Zuzu is bound beside him. Yuya calls Zuzu's name and Declan angry asks if Roget intends to continue. Roget rips off the visor and he furiously asks how much further Declan will go to make Roget take the fall for Declan; using these Lancers as a front and acting like some kind of hero? Yuya, Sylvio and Gong all gasp and Gong asks what Roget means.
Roget explains that Declan's father – Leo Akaba – is the Professor himself; their enemy and the leader of Duel Academy. Yuya repeats Leo Akaba's name and Sylvio protests that Leo is the founder of both LID and the Leo Corporation. Gong is shocked that Declan's father is the Professor. Roget observes that the Lancers were all tricked into helping Declan with his dimensional war. Yuya asks what Roget means and Roget claims that the Akabas have started a dimensional war as father and son and are trying to take over all four dimensions; the father would have his stronghold in the Fusion Dimension and attack the Xyz Dimension, while the son would have his stronghold in the Standard Dimension and attack the Synchro Dimension. The Lancers are the vanguard for that very plan and hindrances like Roget are to be eliminated. He laughs and dubs it a finely written script; with this Declan will take over as the king of New Domino City and the Synchro Dimension in place of Roget.
As Roget laughs madly, Declan adjusts his glasses and he points out that even if he were allied with Leo Akaba, why is Roget taking Zuzu back to the Fusion Dimension? Roget flinches and Yuya accuses him of lying, stating that he believes in Declan Akaba, who isn't like Roget, who only thinks of himself. Declan smiles at Yuya's trust, and Yuya tells Roget to give Zuzu back. Roget replies that that will never happen. He will live on, and Zuzu Boyle is his lifeline to ensure that. He smiles creepily at the horrified Zuzu and vows that he will never let her go before he releases her energy bonds and then drags her away. The shimmering walls fade, and Yuya calls Zuzu's name and the Lancers head after Roget.
Roget and Zuzu descend in an elevator, entering a vast room with a pillar in the middle and only four walkways extending from it in the shape of a cross to support it. Roget muses madly to himself that he shouldn't have bothered with Declan and should only have brought Zuzu Boyle with him. Zuzu looks at him in terror as Roget muses that even with just this girl, he's sure that the Professor will be happy. He claims that he will still survive. Crow's voice comments that he wonders about that, and Roget looks outside the elevator to see Jack and Crow standing there with activated Duel Disks and "Assault Blackwing - Raikiri the Rain Shower" and "Scarlight Red Dragon Archfiend". Crow tells Roget that they won't let him escape and Jack declares that he'll have Roget take responsibility for plunging New Domino City into chaos. He orders "Scarlight Red Dragon Archfiend" to get Roget with "Absolute Powerflame". "Scarlight Red Dragon Archfiend" smashes the elevator with a flaming punch, knocking both Roget and Zuzu out, much to Jack's horror.
Yuya swings over the chasm of the room on "Performapal Whip Snake", calling Zuzu's name. He lets go and catches her, then he calls "Hippo!" "Performapal Hip Hippo" runs along the slanted protrusions of the wall and launches itself into the air; Yuya closes his eyes and braces himself as he lands on the back of "Hip Hippo". "Hip Hippo" lands and disintegrates, lowering Yuya and Zuzu to the ground. Yuya desperately cries Zuzu's name, and as the other Lancers run up he tells Zuzu that she's safe now. Zuzu opens her eyes and whispers Yuya's name. Yuya hugs her tearfully, sobbing that he finally found Zuzu. Zuzu closes her eyes and rests her chin on Yuya's shoulder as she begins to cry as well, while the assembled Lancers, Sora, Jack and Crow smile (and Gong cries manly tears). Even Declan and Shay smile at the reunion and Declan adjusts his glasses.
"Damn you…" Roget's voice mutters. Shay yells Roget's name. Roget climbs back onto the walkway and he asks if they think that he will let it end like this. Sylvio is shocked that Roget survived. Roget gets to his feet, stating that he didn't just build this dimensional transporter to return to the Fusion Dimension, but also to transport the entirety of New Domino City across dimensions once he became aware of the attack of Duel Academy. Crow and Jack are shocked at the implications of this, and Roget staggers to the center pillar, claiming that there is no need to run. Since he is going to be destroyed anyway, then he'll take the rest of them and New Domino City with him. He lays his hand on a console that reads "CHECK" and it shifts to an "H" symbol displaying the word "CLEAR". Roget raises his fist and he screams that he'll drop everything into the void between dimensions, before slamming his fist down onto the console.
Alarms begin to sound, green lights ripple across the wall and surge up at the bottom of the room and electrical arcs begin to crackle over the machine. Roget turns around and he laughs madly, ordering the Lancers to fall as powerful winds begin to swirl in the room. Yuya holds onto Zuzu and the rest of the Lancers brace themselves, but the lighter Riley is swept away and Moon yells his name. Declan runs in and catches Riley, yelling his name. Riley cries, "big brother!" and Declan smiles at him. Jack roars Roget's name and he and Crow send "Scarlight Red Dragon Archfiend" and "Raikiri" in to attack, but the electrical arcs disintegrate the monsters, much to their shock. The green light surges even further, spearing out of the building and into the sky. Outside, the citizens of New Domino City watch in shock; Chojiro stands with the kids and he asks what that is. The Topsiders and Commons alike observe that a bright light is enveloping the Security Headquarters. The light begins to spread in a manner reminiscent of Zero Reverse and Tony, Damon and Shinji watch; Shinji observing that the symbol of the Tops' rule is disappearing.(in the dub Shinji does not say anything.)
Roget laughs, encouraging everyone to disappear. If they won't do as he pleases, then they, this world, and everything should just disappear. A wormhole opens beneath the walkways, and a bolt of electricity strikes the floor, shattering part of the stone and dislodging Roget. With a horrified scream, Jean-Michel Roget falls, disappearing into the wormhole, which closes after he enters it. The light fades and the winds die and Gong asks if everyone is okay. Crow admits that somehow they're okay. Shay observes that Roget disappeared and he asks where Roget went. Zuzu's energy cuffs dissolve, and Zuzu looks up at Yuya, asking where Roget is. Yuya admits that he doesn't know; Roget got sucked into some kind of hole. But Zuzu is right here, and no-one has taken her away. Zuzu tears up again and she whispers Yuya's name. She gently removes Yuya's hands, and Yuya smiles and suggests that they go together. Zuzu nods in agreement.
And then a whining starts; the air fills with green light and the winds begin to whip through the room again. Yuya and Zuzu both ask what it is, and Yuya theorizes that the dimensional transfer device might still be active - and Zuzu is ripped from her feet by the winds. Yuya screams Zuzu's name and Zuzu reaches futilely for Yuya as she is sucked into another wormhole. Yuya screams Zuzu's name again, but then he is pulled into the air as well. Gong grabs Yuya's hand, but even he is beginning to lose his balance; Shay tries to hold Gong back and Sylvio grabs Shay too, but it's not enough and all four of them are sucked into the portal.
The light fades and the Akabas can only stare in shock. Crow and Jack walk up and Crow asks what just happened. Declan explains that it was most likely caused by Roget's dimensional travel device going haywire; a wormhole. Jack asks what a wormhole is, and Sora explains that it connects dimensions. Declan confirms it; but he explains that it doesn't move things over to a specified route. Riley asks where Yuya and the others are and Declan admits that they are most likely in another dimension, but the methods to determine which one do not exist.
The group regains consciousness in the ruins of a destroyed city and a smoky sky. Sylvio asks in shock if New Domino City was destroyed, but Shay grimly tells him that it wasn't - this is Heartland, in the Xyz Dimension, his home.
Featured Duel: Declan Akaba vs. Jean-Michel Roget
Turn 2: Declan
Declan activates "Forbidden Dark Contract with the Swamp King", which lets him Special Summon a Level 5 or higher Fiend-Type monster from his hand, with its effects negated. It cannot attack and is destroyed during the End Phase. Declan Special Summons "D/D/D Chaos King Apocalyspe" (2700/2000) via this effect. Since he used the first effect of "Forbidden Dark Contract" to Special Summon a monster, Declan activates its other effect, which allows him to use the Special Summoned monster as Fusion Material for the Fusion Summon of a Fiend-Type monster, using monsters in his hand or field; however, he will take 2000 damage during each of his Standby Phases. He fuses "Apocalypse" with the "D/D Lamia" in his hand to Fusion Summon "D/D/D Dragonbane King Beowulf" (3000/2500) in Attack Position. Declan activates the effect of "D/D Lamia", which allows him to Special Summon it from the Graveyard by sending 1 "D/D" or "Dark Contract" card from his hand or field to the Graveyard, but it is banished when it leaves the field. He sends "Forbidden Dark Contract" to Special Summon "Lamia" (100/1900) in Attack Position. Declan activates "D/D Savant Thomas" ( 6) and "D/D Savant Nikola" ( 8) in his Pendulum Zones. Declan Pendulum Summons "Apocalypse" (2700/2000) from his Extra Deck in Attack Position. He tunes the Level 7 "Apocalypse" with the Level 1 Tuner monster "Lamia" to Synchro Summon "D/D/D Cursed King Siegfried" (2800/2200) in Attack Position. He activates the effect of "Siegfried", which allows him to negate the effects of a Spell/Trap Card on the field until the next Standby Phase. Declan negates "Ancient Gear Magic Shield" ("Ancient Gear Howitzer": 3000 → 1800). "Beowulf" attacks and destroys "Ancient Gear Howitzer", with the effect of "Beowulf" inflicting piercing battle damage (Roget: 4000 → 2800 LP). "Siegfried" attacks directly (Roget: 2800 → 0 LP).
"Roget" re-joins the Duel, taking the 2000 LP intrusion penalty (Jean: 4000 → 2000).
Turn 3: Roget
Declan activates the other effect of "Apocalypse", which lets him Special Summon it (2700/2000) from his hand by destroying two face-up Spell/Trap Cards he controls. He destroys "Nikola" and "Thomas". Since "Nikola" was destroyed while it was in the Pendulum Zone, its effect activates, allowing Declan to return a "D/D/D" monster he controls to his hand, and then place up to two face-up "D/D" Pendulum Monsters from his Extra Deck to his Pendulum Zone, but their Pendulum Effects cannot be activated this turn. "Apocalypse" returns to Declan's hand and "Thomas" and "Nikola" are placed in his Pendulum Zones. Since a "D/D" Pendulum Monster was returned to his hand, Declan activates his face-down "Dark Contract with the Swinging Abyss", which allows him to inflict damage equal to the DEF of one "D/D" Pendulum Monster that was returned to his hand (Roget: 2000 → 0 LP).
"Roget" rejoins the Duel, taking the 2000 LP intrusion penalty (Roget: 4000 → 2000). Since the combined effects of "Apocalypse", "Nikola", and "Swinging Abyss" form a controlled loop, Roget would end up being defeated each time he reentered the Duel. Knowing that he cannot win, Roget terminates the Duel and flees.
The following cards appeared in this episode. Cards in italics debuted here.