Ryoga Kamishiro ( manga ) Ryoga Kamishiro , nicknamed " Shark " , is one of the main characters in the " Yu - Gi - Oh ! ZEXAL " manga and is one of Yuma Tsukumo ' s rivals . According to Kazumo Tsukumo , he is the Duelist who has the soul that governs the oceans of the Astral World . Design . Appearance . Shark has dark blue eyes , pale skin and dark purple hair , which resembles tentacles hanging down , referencing his Deck theme of aquatic creatures . His accessories include a grey , shark tooth - shaped pendant , and two grey rings on his right hand . He also owns a grey and green Duel Gazer with a red lens and a yellow spike . He also wears a large red jeweled , yellow pendant that resembles a Barian Emblem . His attire includes a dark purple jacket over a black shirt and dark pants with white , green - gems shoes . When in his school attire , he wears a white shirt with green - lined sleeves , tie and a collar . Personality . Ryoga has been shown to be extremely cruel , shown when he snatched Tetsuo ' s Deck and then snapped Yuma ' s pendant just to show Yuma that he was powerless . Despite this , he is shown to keep his word as he gave Yuma Tetsuo ' s Deck after he was defeated . Biography . History . Shark is an orphan , and was raised in an institute , together with Kyoji Yagumo . He and Kyoji were like light and shadow there , but they weren ' t on bad terms . Once , both he and Kyoji entered the Duel Monsters Regional Cup . There , Kyoji wanted to steal the Deck of the person who was most likely to win the tournament , but failed , and Shark took the blame for it . Yu - Gi - Oh ! ZEXAL . One day after school , Shark had a Duel with Tetsuo Takeda , which was watched by Yuma Tsukumo and Kotori Mizuki . When Shark defeated Tetsuo , he took his Deck . Tetsuo revealed that Shark and his friends had taunted Tetsuo to the extent that he bet his Deck on the Duel . Yuma attempted to defend Tetsuo , but Shark took Yuma ' s pendant and snapped it . He then told Yuma to challenge him to a Duel in front of the Heartland train station in order to win Tetsuo ' s Deck back , but he must put his Deck on the line . Shark overpowered Yuma during the Duel , but when Yuma decided to believe in himself , his broken pendant restored itself , and Yuma uses it to open the door of his dreams . When he does so , a dark card , called a " Number " , possessed Shark , making him even stronger . However , at the same time , a mysterious entity , called Astral appeared before Yuma , and told him to " stand up and win " . Astral then helped Yuma during the Duel , but they find out a " Number " can only be destroyed by another " Number " , and when two of them battle , they do to consume each other . Astral gave Yuma a " Number " as well , and they managed to defeat Shark . As Shark gave Tetsuo ' s Deck back , Yuma said that the Duel was fun , and that they should Duel again . Shark said that he won ' t forget that , and leaves . Shark later appeared after Yuma was almost defeated by Kaito Tenjo , looking annoyed at how Yuma was behaving because of his defeat . After Yuma defeated Cologne , Shark walked down an alleyway , and was approached by a stranger , hiding her identity beneath a cloak . She soon revealed herself as Luna , and said that Shark can call her an emissary from the moon . Shark replied that she looks like something straight out of a fairy - tale , not that he hates them . Luna replied that she doesn ' t have any ill will against him , but she must face him . They then began a Duel . The Duel ended quickly , with Shark defeating Luna in an OTK . After he won , Shark asked Luna if she is alright ; she is impressed that Shark could Summon three Xyz Monster s at once during the Duel , and said that she wasn ' t wrong . Luna revealed she is a Numbers Hunter whose goal is to eliminate the " Numbers " , and says that Shark is the only one who can stop Dr . Faker , and for that he needs the power to do so - a " Number " . Shark declined , saying that he was already once possessed by a " Number " , and that he cannot do so . However , Luna replied that he knows how terrifying a " Number " can be , and that this is just why it would be okay . She further explained that " Numbers " are mirrors that reflect the hearts of the people , and at that time , his heart was full of darkness , but Yuma and Astral freed him from that darkness . She then gave Shark , and said that it ' s a new power that will protect him Later , Shark Duels a self - made store owner , whose business was going well because of the power of a " Number " card . Shark won easily using the new " Number " Luna gave him , " " , and obtained the store owner ' s " " . Then , Yuma and Astral appear , and meet him . Before they could say anything , Kaito Tenjo appeared as well . Shark recognized Kaito , and Kaito says that as Shark knows his name , he seems to have became rather famous . Luna then appeared , and told Kaito that ' s because she told Shark the truth . Later , when Kaito tried to use his Photon Hand on Luna , she put her hand over the amulet on her chest , which created a kind of barrier covering her , Shark , Yuma and Astral , and reflecting the Photon Hand . The four are then instantly transported to the outskirts of Heartland City . Yuma and Shark stared at each other for a moment , and Shark told him that he would wipe out his " Numbers " as well one day , as he turned to leave with Luna . Following this , Shark speaks with Luna and he thanks her for the " Number " she gave him as it allowed him to see something interesting . Luna mentions now that Kaito has shown up along with Yuma and Astral , all the players are now in place . All except for one Shark adds . Shark says that if what she said is true then he must know the truth as that is the reason he decided to help her destroy the Numbers . Luna responds " Kyoji Yagumo . . . The one who changed your fate . . . " . As Shark stares at the moon , he thinks to himself that if Kyoji is going to make the wrong move he ' ll be there to stop it . Shark thinks back to his time at the orphanage and Dueling Kyoji in a tournament as Luna correctly guesses that Shark took the fall for Kyoji when he stole that Deck . Shark grits his teeth as he wonders why Kyoji stole the Deck in the first place as he was the hope of the children in the orphanage . When Yuma begins a Duel with Eviluder , Shark and Luna watch from a rooftop . Luna asks Shark if he is going to make a move and Shark replies that now is not the time as he notices Kaito is watching the Duel as well . Shark becomes surprised when he sees the size of Eviluder ' s " " . After the Duel ends with Yuma ' s victory Kyoji appears and punishes Eviluder for losing . Kyoji notices Shark and admits that its been a long time since they last met . Shark asks what happened to him and Kyoji responds that Shark has gotten rude after he last saw him . After remaining silent for a bit , Kyoji tells Shark that hope and despair are two sides of the same coin and that if one has great hope the deeper the despair they will have . Kyoji tells Shark that he is special to him and one day he will teach him what it means . With those words Kyoji leaves . Shark tells Kyoji to wait but Luna says they must leave as well as they can ' t afford to do anything foolish right now . Shark defeated Shadow and claimed " " at some point . Soon after , he Dueled Kaito for his " Numbers " . Shark used " Anchor Whale " to nullify the effects of " Galaxy - Eyes Photon Dragon " and transform the field into a deep - sea field , pushing Kaito into a corner . He continued to gain an edge through destroying " Galaxy - Eyes " and a combo of his " Nightmare Shark " and " Bahamut Shark " , but Kaito used " Hyper Galaxy " to bring back his ace and reduce Shark ' s Life points to 1600 . Unfortunately , as Shark still held " Abel ' s Doom " , and Kaito had " " , the trap Shadow had set was complete , causing the two " Numbers " to summon themselves , reduce both their Life Points to 1000 , and wipe out both players ' fields , setting the stage for a double knockout . Yuma began a Duel to save them , paying 2002 of his Life Points to offer half the amount to each of them as " Cain ' s Doom " and " Abel ' s Doom " continued to attack each other . During the Duel , Yuma continuously tried to sacrifice his own life for Kaito and Shark ' s sake , with both being against it . Their wishes to defeat Shadow created a strong bond between them , causing Astral to shine brightly and give birth to " " , leading Yuma to victory and rescuing Kaito and Shark from a narrow defeat . . Later on , Kyoji set a double Duel between Yuma and Kaito , and between Shark and himself , in order to end the Numbers War . Shark quickly Summoned " Bahamut Shark " and " Number 47 : Nightmare Shark " , but Kyoji countered him with " " , whose effect destroyed both of Shark ' s monsters . Kyoji then explained to Shark about the effects of " Lancelot " , saying that it was easy for him to surpass Shark then . Before going on with his turn , Shark asked Kyoji what caused him to fall that far , with Kyoji agreeing , explaining that he did want Shark to know what happened to him . Joking , Shark said that it should be good , and asking if it was hell ; trembling , Kyoji said that yes , it was indeed hell , and explained that his brother died by his own hand . Kyoji then explained to Shark about the history involving him and his brother . Shocked at what he just heard Shark asks Kyoji again what happened to him . Kyoji responds that he just told him it was hell . Luna calls Shark on his D - Pad and asks him to stop the duel and not to use any more numbers or the device that Kyoji created will activate . Shark admits that she ' s right about not summoning any numbers to the field , but he refuses to stop the Duel as his pride as a duelist won ' t allow it . Using a combo of the trap Hidden Fangs of Revenge and the effect of Medusa ' s Aegis allows Shark to destroy Kyoji ' s monster . Number Hunting . During his Duel against Yuma , Shark came in contact with " " , which possessed him . He lost the card to Yuma and Astral afterwards , when he was defeated . Shark became a Number Hunter at the behest of Luna , who gave him " " . He would go on to win " " from a restaurant owner and " " from Shadow . The latter card was eventually passed to Astral . During the Duel against E ' Rah , Kyoji Yagumo handed Shark a blank " Number " , previously " " , which was moulded into " " during the same Duel . After E ' Rah ' s defeat , Astral absorbed all the " Numbers " held by Ryoga . Deck . Ryoga plays a WATER Deck , with a heavy focus on Xyz Summon ing using the effect s of cards such as " Chain Summon " and " Bahamut Shark " , which is his ace monster . When he received " " from Luna , his strategy starts to focus on bring him out quickly , the majority of the times using the effect of " Bahamut Shark " , so that he can allow the latter to attack directly .