Inside The Emperor's Key, Astral unlocks his next lost memory, the number eighty-three. He muses that the gears in the giant puzzle began to move when the scattered "Numbers" cards were brought back. The machine has the same amount of gears as Astral hast lost memories - ninety-nine. He wonders if the structure is meant to be some sort of message and why it would be in Yuma's key. He wonders if someone predicted that his memories would be lost.
Meanwhile, Yuma is late for school. He dashes across a crosswalk when traffic is cleared, but nearly gets run over by someone on a motorcycle. The driver pulls over and Yuma angrily asks if he didn't see the lights change. He sees that the driver is Shark, who says nothing and pulls away. Yuma wonders where he could be going and hears beeping - he's still in the middle of the street. He dodges the cars and makes it to school. When he gets there, Takashi approaches him and immediately asks to see his Deck. He looks through it and remarks that there are no "Numbers" cards. Yuma responses that they don't show up in his Deck unless "he" is around. Takashi asks who that is, and Tori tells him Yuma means Astral. Takashi tells him that without his "Numbers", Yuma is nothing but a terrible Duelist. Yuma asks what that attitude is about, since that would mean that all his victories were due to "Numbers" and Astral. Takashi tells him that is the case, without them, he wouldn't be able to beat someone like Shark or Tokunosuke. Yuma tells them that they don't know the power of his "bringing it to 'em", telling them that his "Duel sphinx" goes up dramatically. Tori asks what he means by sphinx and Bronk responds he means "tactics". Tori muses that Bronk is like Yuma's human translator.
Takashi asks if Yuma can prove his strength without "Numbers". Yuma responds that of course he can and that he'll challenge Shark again. Yuma wants to go to Shark's place right away, and Bronk tells him that Shark hasn't been showing up to school lately. After losing to Yuma, Shark's reputation dropped dramatically. The rumors say he's been hanging out with some "bad guys". Later, Yuma wanders the streets, remarking that his friends don't understand - he's much stronger than he was before. Astral appears and asks where Yuma is going. Yuma asks why he's come out at time like this and even says that the situation is all Astral's fault to begin with. Astral asks how that could be and Yuma says he's going to Duel Shark again. Astral asks why and Yuma simply says he doesn't need to know and that Astral has no place in the Duel. As he descends a set of stairs, he states that Astral getting involved would just make the situation worse. Tori and Bronk run up behind him, asking if he really intends to go through with this. Yuma tells them of course he does. They arrive at a dilapidated arcade, whose neon lights flash incessantly. Bronk says this is a dangerous place. They enter and Astral remarks that it's an unusual place. Tori suggests they go back, just before Bronk is grabbed from behind by a muscular thug. He asks what they're doing here - this is his territory. Yuma tells him to get his hands off of Bronk and is himself grabbed by another thug, who holds him upside down by the leg, remarking he has great spirit. Five more men emerge and Yuma says he's here to settle things, struggling against his captor. Astral tells him that it would be better if he stopped - the physical difference between the two is too great. Yuma tells him to be quiet. Yuma's captor asks Bronk's what they should do with them, calling him "brother". Shark emerges and tells them to let them go. They ask if he knows them and Shark says he does. Yuma's captor tells them that in that case, they'll get away with their lives. They drop Bronk and Yuma, and leave. Shark tells them they shouldn't have come here, and moves to follow the thugs. Yuma says they came to find him and asks to Duel again. Shark tells them that's impossible - he's quit Dueling and never intends to play again. He leaves without saying another word.
As they walk home, Bronk remarks that Shark has really fallen and that those two brothers are notorious Duelists - they enter tournaments and are known for blackmail and cheating. Astral wonders why Shark would quit Dueling and Yuma wonders the same. Bronk says it's because he lost to Yuma and that there are things that one can never get back after losing. Bronk remarks that he had heard that Shark's turning point was during a National Championship, thinking something else may have happened to him there. That night, Yuma speaks with Astral. He remarks that Shark loved Dueling with all his heart. The next day at school, Yuma's friends see Yuma isn't there. He's returned to the arcade to speak with Shark again. He asks to Duel and asks what's so fun about hanging around with those thugs. Through a Duel, he could understand the whole situation. Shark reiterates that he's given up Dueling and tells Yuma to mind his own business before running off. Yuma chases him. Shark leaps over a fence, while Yuma fails to.
Shark successfully hops from one platform in a pool to another, while Yuma fails to. Shark finally stops, tired and believing Yuma gave up. Yuma immediately shows up behind him and asks to Duel yet again. Shark asks Yuma just what is wrong with him - why would he insert himself into Shark's business. Yuma responds that it's because they're friends - he believes that when two people Duel, they go from being strangers to being friends. He asks if Shark feels the same and Shark asks if Yuma is really serious about that. Yuma tells Shark that if he loses, he'll leave the gang. Shark asks what Yuma would bet in return and Yuma responds that he'll bet The Emperor's Key. Astral tries to stop him, but Yuma just tells him to shut up. Shark tells him not to regret it - this time, Yuma will lose what is most important to him.
Later, the two stand across from one another, ready to Duel. Astral asks Yuma if he's sure he want to do this and Yuma again tells him to that his Duel has nothing to do with him and that he won't use "Numbers". Astral asks why as Bronk, Tori and Takashi arrive. Yuma responds that because only a "Number" can destroy another "Number" and Shark has none. Yuma asks how he could use them so shamelessly against someone who has none. Yuma is still confident he'll win, believing that he's gotten much better since last time. Astral agrees to stay quiet and watch. Shark thinks that he could never forget his loss to Yuma and that maybe deep in his heart he's been waiting for this. Both Duelists set their Duel Disk and Duel Gazers and the Duel begins. Yuma goes first, drawing a card. He Normal Summons "Gogogo Golem", who emerges from the ground. Astral tells him to be careful - Shark has many powerful monsters. Having only "Gogogo Golem" on the field is not good enough. Yuma tells him he already has a plan, Setting a card. Since he cannot attack on the first turn, he ends his here. Yuma thinks that his Set card should protect him. It is "Battle Break", which can destroy an attacking monster and end the Battle Phase. Shark draws. He Normal Summons "Friller Shark". Astral wonders what he's planning by Summoning a monster with only 700 ATK. He then Special Summons the "Shark Stickers" in his hand via its own effect, which can be activated when another Fish-Type monster is Summoned. Astral remarks that Shark has two Level 3 monsters. Shark overlays them to Xyz Summon "Submersible Carrier Aero Shark" in Attack Position. Despite having 100 more ATK than "Gogogo Golem", Yuma is confident his Set card will protect him.
Shark uses the effect of "Submersible Carrier Aero Shark". He detaches the overlaid "Friller Shark" to inflict 400 damage to Yuma for each card in his own hand. Shark has four cards in his hand, so Yuma will take 1600 damage. "Submersible Carrier Aero Shark" fires four torpedoes at Yuma. Shark activates "Mystical Space Typhoon", destroying Yuma's Set card. "Submersible Carrier Aero Shark" attacks and destroys "Gogogo Golem" with "Big Eater" and Yuma's Life Points drop to 2300 as he is thrown to the ground. Shark Sets a card and ends his turn. Takashi is amazed that Shark nearly halved Yuma's Life Points in one turn, and Tetsuo says in turn that Shark really is impossibly strong. Shark asks Yuma what's wrong - didn't he come here to defeat him again and make fun of him? Yuma tells him he's wrong, but thinks that he can't do much without his "Numbers" right now. Yuma draws "Monster Reborn and Normal Summons "Gagaga Magician". Yuma examines his hand, which contains "Stinging Swordsman", "Monster Reborn", "Attraffic Control" and "Zubaba Knight". He could use "Monster Reborn" to revive "Gogogo Golem" and overlay his monsters to Xyz Summon "Number 39: Utopia". Shark tells him to bring it on and to use his "Numbers" trump cards. Tetsuo says that Shark should already know that only a "Number" can destroy another "Number". Shark asks if Yuma really thought he could beat him without them. Shark says that a victory for him will only mean something if Yuma uses "Numbers". Astral tells him that's the only way he can win right now, and Yuma agrees with him. He now realizes that the Duel isn't about Yuma's pride - he needs to save Shark. Yuma plays "Monster Reborn" to revive "Gogogo Golem" and then overlays it with "Gagaga Magician" to Xyz Summon "Utopia" in Attack Position. Yuma's friends are surprised he would break his promise.
"Utopia" attacks "Submersible Carrier Aero Shark", but Shark calls him naive, activating the effect of the "Friller Shark" in his Graveyard. He can banish it to negate an attack and decrease the ATK of the attacking monster by 500. Shark then activates his face-down "Fish Rain", Special Summoning "Big Jaws" from his hand in Attack Position as a Fish-Type monster was banished. Yuma is shocked his attack failed. Astral tells him he made a mistake since he was too eager to win. He reminds Yuma that "Monster Reborn" can be used on an opponent's monster as well. He could have revived "Friller Shark" and then changed the Level of "Gagaga Magician" to 3 via its own effect. He could have then overlaid them to Xyz Summon "Number 17: Leviathan Dragon". The effect of "Friller Shark" could not have been activated. Yuma says that everything is still fine. "Utopia" has 2000 ATK and Shark has no monsters on the field that can destroy it. Yuma ends his turn. Shark draws and then activates the effect of "Submersible Carrier Aero Shark", detaching its remaining Overlay Unit to inflict 800 damage to Yuma since he has two cards in his hand. Yuma's Life Points drop to 1500 as two more torpedoes hit him. He Normal Summons "Skull Kraken" in Attack Position. Yuma isn't happy to see two Level 3 monsters, but Astral tells him not to panic - Shark has no cards that can destroy a "Number". Shark overlays "Skull Kraken" with "Big Jaws" to Xyz Summon "Black Ray Lancer" in Attack Position, saying that this Duel is his. He activates the effect of "Black Ray Lancer", detaching an Overlay Unit to negate the effects of "Utopia" until the End Phase. "Black Ray Lancer" absorbs an Overlay Unit into its spear and launches a red X at "Utopia", surrounding it in waves. Shark declares that even if "Numbers" can't be destroyed, that is only a card effect. If the effect is gone, any monster with sufficient ATK can destroy a "Number". Yuma is shocked that effect of "Numbers" were negated. "Black Ray Lancer" attacks and destroys "Utopia" with "Black Spear", skewering it through the chest. Yuma drops to his knees and screams "Hope!" (the Japanese name of "Utopia" is "Aspiration Emperor - Hope"). Astral remarks that Shark found the weakness of the "Numbers". "Submersible Carrier Aero Shark" attacks directly with "Big Eater", dropping Yuma's Life Points to zero.
Shark remarks that it was almost too easy. He thinks it's laughable that he lost to Yuma earlier. He walks over the Yuma and tears The Emperor's Key from his neck, saying he'll take this as promised. Shark recalls Yuma's comment about friends and begins to walk away. He then states that destroying the Key wouldn't be worth it, and tosses it to the ground behind him. Shark walks to his motorcycle and Yuma tells him to wait. Shark tells him that he doesn't understand - he's staying with thugs because he wants to. They gave him a place to stay when no one else would. He tells Yuma not to get involved with him again and rides off.
Yuma Tsukumo vs. SharkEdit
Turn 2: Shark
Shark Normal Summons "Friller Shark" (700/1500) in Attack Position. The effect of the "Shark Stickers" in his hand activates and it is Special Summoned in Attack Position (200/1000). He overlays his two monsters to Xyz Summon "Aero Shark" (1900/1000) in Attack Position. Shark detaches the overlaid "Friller Shark" to activate the effect of "Submersible Carrier Aero Shark", inflicting 400 damage to Yuma for each card in Shark's hand (Yuma 4000 → 2400).[Notes 1] Shark activates "Mystical Space Typhoon", destroying Yuma's face-down "Battle Break". "Submersible Carrier Aero Shark" attacks and destroys "Gogogo Golem" (Yuma 2400 → 2300) and Shark Sets a card.
Turn 3: Yuma
Yuma draws "Monster Reborn" and Normal Summons "Gagaga Magician" (1500/1000) in Attack Position. Yuma's hand contains "Stinging Swordsman", "Monster Reborn", "Attraffic Control" and "Zubaba Knight". He activates "Monster Reborn", Special Summoning "Gogogo Golem" from his Graveyard. He overlays his two monsters to Xyz Summon "Number 39: Utopia" (2500/2000) in Attack Position. "Utopia" attacks "Submersible Carrier Aero Shark", but Shark removes the "Friller Shark" in his Graveyard from play to decrease the ATK of "Utopia" by 500 and negate the attack. Shark activates his face-down "Fish Rain", Special Summoning "Big Jaws" (1800/300) from his hand in Attack Position as a Fish-Type monster was removed from play.
Turn 4: Shark
Shark detaches the "Shark Stickers" overlaid with "Submersible Carrier Aero Shark" to activate the effect of "Submersible Carrier Aero Shark", dealing 400 damage to Yuma for each card in Shark's hand (Yuma 2300 → 1500). Shark Normal Summons "Skull Kraken" (600/1600) in Attack Position. He overlays his two monsters to Xyz Summon "Black Ray Lancer" (2100/600) in Attack Position. Shark detaches one of the overlaid monsters to the Graveyard to activate the effect of "Black Ray Lancer", negating the effects of "Utopia" until the End Phase. "Black Ray Lancer" attacks and destroys "Utopia" (Yuma 1500 → 1400) and "Submersible Carrier Aero Shark" attacks Yuma directly (Yuma 1400 → 0).
The following cards appeared in this episode. Cards in italics debuted here.