|“|| (JP): Flame of apocalypse that burns away everything in this world! Ride the Vanguard! Dragonic Overlord!|
(EN): Ride the Vanguard! Burn everything in this world to ash with your apocalyptic fire! Dragonic Overlord!
—Toshiki Kai, Whenever he rides Dragonic Overlord.
Toshiki Kai is one of main characters in the anime and manga. During Season 4, he becomes the main protagonist after Aichi's disappearance. He is also the main protagonist of Neon Messiah, along with Aichi. He is a very serious character. It is known from the end of episode 1 that he had previously met Aichi and gave him the card Blaster Blade, which later becomes the heart of Aichi's Royal Paladin deck. His Vanguard Circle color is red.
Despite continuous reference to 'Kai' both in-series and out, Kai's given name is in fact Toshiki. Going with Japanese rules of etiquette, none of the characters in Vanguard refer to Kai by his given name because none of them are close enough to him socially to speak to him as such, much like how Mr. Mark only refers to Aichi as Sendou, and Katsumi Morikawa refers to Kamui as Katsuragi.
Kai is a serious person and doesn't like to joke around like other people his age. He doesn't talk much or to anyone. When cardfighting, he is shown to be more serious and confident on winning the game without any need of support. Despite his selective mute personality, he has a best friend, who is Taishi Miwa.
There is also some speculation and various scenes in the anime that suggest Kai may have a soft spot for Aichi, even though he refuses to admit it. Often times, his friend Miwa will tease him about it. According to Miwa, Kai used to be more friendly before he moved away.
Kai is shown to have some knowledge when it comes to cooking and especially like onions. Whether this stems from him living alone and having to fend for himself remains to be seen.
He shares the popular phrase, "Final Turn!" with Ren Suzugamori, though Aichi recently adopted it as well as he got corrupted by PSY Qualia. This probably came from the fact that Ren and Kai were once on the same team.
After the VF Circut, Kai adopts friendly personality towards Miwa and the rest of his friends at Card Capital, which he goes to a lot now, but still retains his seriousness and confidence. He is shown to be more supportive and helpful with his school's Cardfight Club; he loaned Morikawa his old Kagero deck and helped Izaki train for the Highschool Vanguard Championships, showing he now tolerates the two. This extends outside of the club, shown with Aichi when he gives him advice, and Naoki after their fight. However, while watching how Aichi was able to defeat his old Kagero deck, and his match against Ren, he starts to feel inferior after witnessing how much their skills have grown, lamenting that he would probably lose if he fought them as he is currently.
After he became Reversed, Kai becomes obsessed with challenging strong fighters so Link Joker will become stronger. When facing such a fighter, for example Kenji, Kai will remark on that strength, saying that it is what he has been looking for.
His manga counterpart personality differs from his anime counterpart. He still is very much a serious person and is quite confident of him winning cardfight battles. Although he retains his seriouses, he actually enjoys going to Card Capital and smiles quite often. He seems more friendly and supportive towards Aichi. Also, he appears to talk more towards Miwa.
In Episode 162, however, Kai shows a different side to him. Horrified by what he's done, Kai challenges Aichi and reveals that what he's done hasn't caused anyone any happiness, and attempts to go into self-exile or even suicide in order for Aichi to find joy.
In Season 4, he starts to open up more and becomes friendlier than he was in the previous seasons. He also considers to keep his mates out of danger that shows he cares about his friends(Mates).
Despite not having PSY Qualia himself, Kai possesses a few abilities reminiscent of said power. The most notable is his bond with Dragonic Overlord, which throughout the series has evolved to match Kai's feelings. When he was searching for the power to beat Ren, it evolved into Dragonic Overlord the End. When Kai was Reversed, it evolved into Dragonic Overlord "The Rebirth". When he learned the value of mates, it evolved into Perdition Emperor Dragon, Dragonic Overlord the Great. Also, he was able to see Brandt.
Kai was first seen in the local card shop, cardfighting with Morikawa and won him easily as he rides his trump card, Dragonic Overlord. Then Morikawa requested a rematch, at first Kai rejected it, reasoning that he was not strong enough but accepted when he bet a card which attracted his attention, Blaster Blade, a card he stole from Aichi. Kai disposed him easily and took the card, then Aichi came and challenge him to claim back his card. Kai accepted the challenge and teaches him the rules because Aichi was a beginner in Cardfight!! Vanguard. Before the cardfight start, Kai returned the card to Aichi, hoped that he will use it effectively against him. Throughout the fight, Aichi learned that Kai was the one who gave the card to him during his childhood. Eventually, Kai lost the game and returned the card to Aichi, though he purposely held back during the fight.
Kai was seen again when Aichi and his friends spotted him walking back to his home. They decided to follow him secretly due to their curiosity. But soon, Kai found out they were tailing him. Aichi apologizes and asks him for another battle, but he declines it. However, when Kamui challenged him, he accepted it with an askance look. The next day, the two commence their fight. At first, Kai took the upper hand by riding a Grade 3 card very quickly, but shortly afterwards, Kamui countered it with his own Grade 3 card. However, Kai once again proved that he was the strongest as he rode Vortex Dragon, proceeding to activate its Mega Blast to retire the rear-guard units controlled by Kamui, leaving Kamui defenseless for the final attack from Kai. He left the scene after he defeated Kamui, but not before Aichi told him he vowed to become a stronger and more worthy opponent in order to challenge Kai again.
After that, he entered the Local Shop Tournament, with a hope that he would find some strong opponent. However, he easily reached the Semi-Final in the tournament. After the setup of the Semi-Final round, he was selected to be the next opponent of Misaki. Kai announced "Final Turn" before he easily claimed victory against Misaki. During the final round, he once again defeated Kamui effortlessly and took the champion title. After the tournament, he was invited into the Regional Tournament with Kamui, Misaki and Aichi as a team, calls Team Q4 , short for Team Quadrifoglio.
In the First Round of the Regional Tournament, he annihilates his opponent without even breaking a sweat. Team Q4 easily won the second and third round. During the Finals of the Regional Tournament, he had a close fight against Kaoru but he still won the cardfight with two critical triggers on Blazing Flare Dragon. However, it was shown that Kai purposely let his opponent take the lead before crushing him, hoping to motivate Aichi's will to fight.
After the first Regional championship, Kai starts suspecting that Aichi might have the same ability as Ren. During Aichi's fight with Kyou, Kai confirmed it. Kai, not wanting to suffer what happened with Ren again, he told Aichi that he is not getting stronger, but weaker, and quits Team Q4. He also appears to blame himself for this and for the currently unknown incident that happened with Ren, as shown by how after quitting Team Q4 he said "he made the same mistake again."
Kai later fought against Kourin, who was looking for him and suspecting he also had PSY Qualia, but confirmed he doesn't. Kai also said it is his fault that Aichi obtained PSY Qualia, and that he wants to exceed it. Then he accepted to help stop Aichi before he fully turns into Ren.
Kai cardfights Aichi and talks about his past, how Aichi showed him that Vanguard fights are supposed to be fun and not all about power, later convincing him to abandon using PSY Qualia that true strength does not comes from that power but oneself.
Before the final match of the nationals, he challenges Ren for a fight in order to bring his former self back. Kai draws the card that will be the trump card to beat Ren and crossrides Dragonic Overlord the End saying that he will bring Ren back with this card. But Ren crossrides Phantom Blaster Overlord and wins. Later, he is seen in the match between Aichi vs Ren, where he helps Aichi snap out of PSY Qualia's influence. After the match, he gives Ren and Aichi a smile and thanks Aichi for saving Ren. At the end of the season, Kai finally challenges Aichi to a proper cardfight.
Season 2During this season, he uses a Narukami deck. Kai will be taking part in Asia Circuit and will travel around Asia to fight different fighters.
Kai is first shown fighting against Takuto Tatsunagi, who was using a Gold Paladin deck. Towards the end of the fight, Takuto rides an Great Silver Wolf, Garmore that transforms Kai's Kagero deck into a Narukami deck. The next day, Kai spots Aichi in the park and challenges him to a fight and during the battle, Kai does reveal he believes Aichi's story and starts to have certain memory flashes of Aichi's Blaster Blade.
Kai starts training to become stronger, and fights Kyou on a mountain, and wins the fight, triggering an avalanche, which Kai saves Kyou from it.
During the Seoul Stage, he is seen with Ren and Asaka in his new team, Team New Asteroid, who wins all of their battles against Team Movie Stars in the first round of the Seoul Stage. He fights Kamui in the next match-up against Team Q4, winning the match by taking advantage of the special rule, using Dragonic Kaiser Vermillion's Limit Break twice in the match. He appears beside Tetsu after the match, watching Ren's and Asaka's match. Kai does not have any recollection of PSY Qualia as he did not react when Ren says that the power is incredible. In the final round of the Seoul Stage, he wins the match against Team Caesar's Gai Usui.
Team New Asteroid is invited to a summer resort island to train by the Tatsunagi Financial Group. He watches Aichi and his friends training on the beach. He paired up with Aichi for the Test of Courage and tells him that their paths will cross. Next morning, Kai is asked by Ren to play beach volleyball with him and Asaka, but declines, and asked Miwa out to cardfight with him. Later in the afternoon, he sees Q4 off from land as they go back to Japan, in preparation for the next stage.
Kai and the rest of the winners of each stage gather in Japan, the last stage of the VF Circuit. New Asteroid wanders around the amusement park where the final stage is held. After the winning ceremony, all the teams gather in a room that has a portal that creates a space connected between Cray and Earth to fight a mysterious empty power, Void. New Asteroid gets seperated with the other teams by Leon Soryu not long after their arrival in the space. Ren uses his PSY Qualia to track Leon's whereabouts. After finding Leon, Kai challenges Leon and expresses his anger about "sacrificing" the three clans to bring back Aqua Force. He crossrides Dragonic Kaiser Vermillion "THE BLOOD" to counter Leon's Aqua Force units, but Leon managed to survive and crossrides Blue Storm Supreme Dragon, Glory Maelstrom and takes the win. Kai and his team were sent back to Earth as defeated cardfighters cannot exist in that space.
He is now a second-year student at his high school and is a part of his school's cardfight club. He is seen briefly in episode 107, battling a kid in Card Capital.
During the intermural fight against Aichi's school, he is matched up against Naoki Ishida. He acknowledges his skill in Vanguard as Naoki pushes Kai to 5 damage. However, Kai manages to win the match with Eradicator, Dragonic Descendant and agreed to fight Naoki again. Later in the matchup, he swapped Morikawa's deck with his old Kagero deck. Through that cardfight, he sees Aichi grow even stronger as a player, commenting that even Dragonic Overlord The End could not reach him anymore.
During the tournament, he fights against Shingo crushing him completely commenting that he wanted to fight Aichi instead. But after his team fails to advance and after watching Ren and Aichi's Cardfight, Kai soon realizes that their skills have grown to the point where not even he can reach them anymore. He is later seen in Episode 126: The Mystery Dragon, where he witnesses a Reversed Naoki Ishida cardfight Aichi. After the fight, Kai picks up the mysterious card Eradicator, Vowing Saber Dragon "Reverse," which burns right before his very eyes. He then confronts Takuto Tatsunagi about "Reverse," and ends up cardfighting Takuto's other side, who uses the Link Joker clan in an attempt to Reverse him. Tempting Kai with the power of Link Joker, the agent of Void, he accepts the power of Reverse and becomes a catalyst of what is to come.
The next day, he goes to see Ren to fight him, only to be told by Tetsu that he is not there, so, as an alternative, he decides to fight Tetsu instead with his new power, which Tetsu assumes is a new Narukami unit (as no one other than Takuto and Kai know about Link Joker at the time). He defeats and Reverses Tetsu Shinjou, and walks out Fukuhara High saying he hasn't mastered Link Joker yet. In his quest to master the Link Joker deck, he decides to leave the country running into Kenji Mitsusada, defeating and Reversing him as an unexpected bonus. He is later seen on a plane that is heading towards New York in America, possibly looking for stronger fighters. But it was later revealed that Kai went to New York to reverse countless of cardfighters around the world.
In episode 147, after Kai returned to Japan, Takuto's secretary was sent to drive Kai to meet Takuto but his journey was intercepted by Miwa who seeked answers from Kai. Kai managed to reverse Miwa, revealing that he became a reversed fighter by his own will to be able to fight Aichi and Ren as their equal. He is later seen observing a fight between Miwa and Misaki on top of a building. After witnessing Miwa's loss against Misaki, he now gets into a cardfight with Aichi, saying how he has waited for this moment. He confidently wins the fight, entering the building satisfied with what he had accomplished.
After Aichi and Ren storm the Tatsunagi building, Takuto has Kai fight Ren, a match both has been looking forward to since their fight from Season 1, finally understanding why Ren would ever be tempted by such a power like Psyqualia due to his experience with the Link Joker power. Ren revealed his new crossbreak ride, Revenger, Dragruler Phantom in an attempt to win on final turn. However, Kai manages to hold out and reveals his newest ace card, Dragonic Overlord "The Яe-birth", a Reverse unit that even Takuto did not know existed, and manages to attack him up to three times, the final attack ending on a triple critical. Both knew from the start that Ren could not heal enough times to save himself but continued to damage check anyway because of how much they both enjoyed their cardfight managing to heal twice before submitting. With this victory, Kai became truely satisfied as when Takuto ordered Kai to fight Aichi, he refused because he already defeated him before and thus sidelines himself to observe Aichi and Takuto's fight. After Aichi and Takuto's fight, Kai appears in front of Aichi still reversed saying that he was the opponent he was looking for and challenged him to a cardfight.
Kai states that he is in the middle of being un-Reversed and declares that, at his strongest, he wants to face Aichi at his strongest before he becomes completely un-Reversed and loses his deck. He tells Aichi that not only did he accept Link Joker, but its power never truely took control of him and knew exactly what he was doing. Knowing that, he declares that this will be his last fight against Aichi as he will disappear from his life due to the things he did when he was Reversed. Aichi says that he shouldn't disappear from their lives as Kai had become an example of what he should strive for as a cardfighter. They symbolize this by riding Blaster Blade and Dragonic Overlord, units that have become synonymous with each respective cardfighter. As he tries to overpower Aichi, Aichi manages to hold out his defenses. He finishes the fight with Liberator, Monarch Sanctuary Alfred which superior calls the field including Blaster Blade Liberator which finishes him off. As he is unreversed, Kai understands that by shutting everyone away, he doesn't become stronger but through friends and rivals, one can become stronger and stronger while at the same time raising everyone's strength around them. With this in mind, he has a new plan to get stronger, together with his best friend Aichi.
A while after the end of Link Joker's failed invasion, Kai headed over to Card Capital to see Aichi only for Shin to wonder who he is. Upon asking Emi and later Misaki, they both say that they do not know Aichi and he realizes that something is wrong. Upon entering the Physics room where Aichi would hold his Cardfight club, he is given a Royal Paladin deck with Blaster Blade Seeker. He encounters Naoki who was curious about Kai having forgotten about Aichi as well. He challenges him to a cardfight as he notices that Naoki is getting a reaction upon seeing the deck. Upon riding Blaster Blade, Naoki finally remembers Aichi as they vow to find him. He then challenges Misaki as she got a reaction from seeing Blaster Blade and hopes to trigger that memory with a cardfight. As they fight, Kai attempts to drop subtle hints towards her past when she was using Oracle Think Tank. At the end of the fight, Kai demonstrates Seeker, Sacred Wingal's ability to Legion with Blaster Blade Seeker finally unlocking Misaki's memories of Aichi. Seeing as how these effects triggered both Naoki and Misaki's memories of Aichi, Kai now sees a way to gain allies in search of the missing Aichi.
He seeks Ren as a potential mate but after showing him Blaster Blade, it doesn't trigger any hidden memories and Kai gives up for now. During Kai and Miwa's club meeting (which Morikawa and Izaki are not apart of), he challenges Miwa by giving him his Kagero deck and engage in a match similar to Kai and Aichi's first cardfight. Upon riding Seeker, Sing Saver Dragon and using Blaster Blade to Legion with it, he unlocks Miwa's memories of Aichi.
Upon seeing Ultra Rare on the television, Kai remembers Aichi telling him of a cardshop called Psy that the idol group runs. Hoping to find clues about Aichi's disappearance as well as Kourin's, he goes there. However, instead of finding what he was looking for, he met a mysterious young man named Olivier Gaillard who introduced himself as a Quatre Knight. Gaillard tells Kai to forget about looking for Aichi, but the latter refuses. They engaged in a match with Gaillaird triumphing in the end. Kai suffers judgement after he had lost, which is going through a fire the burns away the person's fighting will, from the result of the Holy Prominence Prison. Galliard then warns Kai that there are other Quatre Knights besides him and that they will destroy anyone that gets in the way, including Kai's mates. Gaillard disappers in a blaze of blue fire afterwards, leaving Kai flat on the ground, agonizing over the the situation in hand. He struggles to get to the others in time as he catches up to Ishida after facing judgement and together finds Miwa in the same way realizing that this may be an enemy they are not ready for. Upon realizing that the Quatre Knights are just going to keep going after Kai's group, he decides to abandon his mates and go after Aichi alone. But Kamui, not wanting Kai to act alone anymore, defeats him in a cardfight saying that as his mates, they are willing to go into these dangerous situations knowing the consequences. Kai relents and accepts the group's help in the end. Then, as Misaki and Kamui are at the airport, he challenges Ren to fight him and learn everything he knows. He defeats him and reveals a stone circle formation which lead them to a portal area which they are greeted by Gaillard who defeats Naoki easily. As Kai gets ready to fight, they are surprised by an appearance by Kourin who allies herself not only with the Quatre Knights, but now uses the Link Joker clan. During their fight, Kai is shown an image of Aichi who tells them to forget about him and leave. While the others believe they are being tricked, Kai acknowledges that this is the real Aichi as his words burn deep as he loses to Kourin. While undergoing Judgement, Kourin takes Blaster Blade Seeker to give back to Aichi as the portals are destroyed.
Needing to train, everyone decides to visit Leon Soryu's island as Kai watches Leon fight Naoki. Leon decides to fight Kai to figure out his thoughts as Kai loses. Leon does not detect any wind behind his actions meaning Kai seems to be lacking something important. Miwa then tosses a Kagero deck to him and realizes that if he wants to get Aichi back, Kai has to be true to himself, which includes going back to his Kageros.
After Naoki finds the entrance to their base, they storm their base in hopes of defeating the Quatre Knights, but under the risk that if they lose, their memories of Aichi are purged as well. Unwavered Kai continues on until he reaches Gaillard after defeating Kamui, he challenges him with his new Legion Perdition Dragon, Vortex Dragonewt, Kai's flames overwhelming Gaillard's. However after defeating him, Kai, Gaillard and Naoki are all trapped in Raul Cera's ice prision with Gaillard's flames beaing too weak after recieving Judgement. With the help of Leon and Ren, they manage to escape. After witnessing Gaillard defeat Raul and enacting Memory Judgement upon him, Kai and Gaillard fight once more unveiling his reborn avatar Perdition Emperor Dragon, Dragonic Overlord the Great and overwhelming him in a heated battle.
He then sets his sights upon Aichi who reveals his corrupted avatar, Star-vader, Blaster Joker and asks that if Kai loses, he become a Quatre Knight, which he agrees on. During the fight Kai kept trying to convince Aichi not to isolate himself from his mates, but Aichi doesn't listen and rides his avatar, Blaster Joker. He then performs Legion with Kourin's avatar Photon. He then demonstrates his Legion's ability Absolute Break that Locked all of Kai's Rear Guards and retires his Mate Neo-Flame. Kai is astounded by this abillity but does not waver, riding Overlord again and performing Legion once more. He trys to win that turn, but Aichi stops his second Legion attack. Aichi once more used Absolute Lock and Break again, retiring Neo-Flame and locking Kai's units. Kai then senses the good part within Blaster Joker and blocks the attack. Kai then declares Final Turn and rides Overlord for the third time, performing Legion once more. Ren notes that Kai was "milking" Legion, but Leon said that it is showing his bond with his mates. Kai has Overlord attack Imaginary Plane Dragon, pulling a Double Critical drive check. He then stands his Legion and attacked Aichi's Legion. Aichi guards, but Kai pulls a Double Critical drive check, breaking through with 5 Critical and leaving Aichi no chance of recovering, thus winning the game.
After the fight, the Seed of Link Joker attacks Kai but Kai calls out to Blaster Blade. Blaster Joker then returns to normal, cutting through the Seed. Then all of Aichi's friends appear as the avatar of Blaster Blade, breaking the Seed into fragments. Then the fragments enter everyone who witnessed the fight. Blaster Blade then says that the Seed will now enter fighters who know forgiveness, saying that one day Link Joker will be accepted by Cray as a new Clan instead of an invader. He then invisions himself sparing with Blaster Dark and Blaster Joker.
The next day after the incident, Kai waits for Aichi at Cardfight Capital after defeating Miwa several times. Once Aichi comes, he then challenges Aichi to a cardfight.
In Episode 194, he was mentioned that several pro collage and leagues were planning on recruiting him but he has not made any plans yet until he appeared at the end meeting Aichi and Naoki at the place the former two first met.
In episode 195, after the graduation ceremony he was finally more interactive with others as he sighed an autograph for a girl who asked for it. At the tournament he was shocked to see Ren wearing his trench coat again and mentioned during his fight with him that he "hated" that Ren's look. In the final round he was about to fight Aichi as he mentioned that he will be going to Europe to fight and train with Gaillard and wouldn't be able to fight with him for a while but Aichi assured him as long as they play the game they will fight each other again as they both open up their vanguards.
In chapter one, he is shown to be fighting Morikawa in a cardfight. He wins against Morikawa. Miwa comes out saying that Kai is the best cardfighter even asking Misaki if there was any other cardfighter that are as good as Kai. Kai went to step out leaving Miwa and the others. He wonders if there was any good cardfighters at all and mentions that he would never get any better than what he is now. He and Miwa were at Card Capital when Morikawa came out again to challenge Kai once more though Kai rejected the invitation when Morikawa pulled out Blaster Blade. Miwa was outcome with joy at that the fact that Morikawa had such a card and asked to cardfight him for the card. Kai was shocked to have seen Blaster Blade wondering where did Morikawa came upon the card. Miwa was able to win against Morikawa making him the new owner of Blaster Blade, but Kai took the card to see if it was the same card. Aichi came running through the shop begging Morikawa for his card back though of course he lost the card to Miwa. Aichi then asked if he could have it back only for both Kai and Miwa to answer that he must win it back through a cardfight. Although Aichi was shy about cardfighting, he admitted that he had a deck and willing to take a challenge from Kai. Since it was his first battle, Kai taught him the basic of the game and gave him Blaster Blade back seeing that his deck probably needed it. Aichi won against Kai and told Kai that he was glad to be able to meet him, saying also that it was fun playing against him.
In chapter 2, he and Miwa is waiting in Card Capital for Aichi to come. They greeted him. Miwa and Aichi fought against each other. Miwa won the battle and said that he was the greatest cardfighter. Kai countered that he always loses to him, but Miwa countered back saying that Aichi won against him. Kai then said that they should cardfight only to be interuptted by Kamui as he make his way to the shop. Kamui asked who was the strongest cardfighter. Miwa said that he was, but Kai said that he lost to him, causing him to say that he lost to Aichi, only for Aichi to say that he lost to Miwa which in turned caused Kamui to spin around in confusion. So he decided to fight against Miwa and Kamui won. Kai told Aichi that he should go against Kamui. Aichi said that he wasn't good though Kai said that he won against him so he should be able to have some skill learned already. Aichi won against Kamui which caused Kamui to say that he will be more like Aichi. Then Miwa said that he should be more like him and not Aichi. This, of course, caused Kamui to see the circle again. Kai is shown smiling at his friends.
In one chapter, it was mentioned by Miwa to Aichi that Kai had planned to make a deck with Blaster Blade back when he had the card. Of course, Kai told him to not bother with this. Aichi was amazed and shocked to know of this.
Back when he was younger, he used to sleep on the park bench. He was awaken by Miwa who brought along a classmate who Kai doesn't even know even though they are classmates. He told Kai that Ibuki was going to teach them how to play Cardfight!! Vanguard. Being the hothead he was, he kept losing to Ibuki. Seeing this, he decided to go home to make his own deck. At home, he began to try to image a winning picture and found one. The next day, he asked Ibuki to fight him. Ibuki was surprised at him using a Royal Paladin deck. Kai said that it was a new clan that focuses on using magic and old tech together. He surprised Ibuki even more when he used Blaster Blade, a unit that is noted by Ibuki that can still grow, in his deck. He then used Blaster Blade Burst to win the battle. Ibuki was happy that Kai was doing something fun. Kai was shown to be walking away when a familiar someone walked along the same path too.
His decks and playstyle has one common theme to it in terms of gameplay, he likes to overwhelm his opponents with high power and multiple stands, especially if it restands the Vanguard, and limit his opponent's options by retiring their units. It's also been said that Kai used to play Royal Paladins in the past.
His main deck focus is the Kagerō clan. His trump card is Dragonic Overlord and later, it's crossride form Dragonic Overlord the End. His strongest and most commonly used cards are normally Flame Dragons. During the Card Capital shop tournament, he also uses Vortex Dragon, using Embodiment of Victory, Aleph's superior ride to speed up it's Soul Charge.
Later in the series, he focuses on the Blazing Flare Dragon's superior ride and uses it during the first Regionals tournament, winning all his matches with it. This deck focuses more on retiring enemy units and units that gets advantage due to that.
After Aichi is tainted by PSY Qualia, Kai switches his deck to the Amber Dragon build and focuses on beatdown strategies due to him being angry at himself for not being able to stop Aichi from getting tainted.
Towards the end of the series, his deck is rebuilt to focus on Dragonic Overlord The End and cards that supports or gets supported by the Overlord series. However with this deck, he did not manage to defeat Ren to bring him back to his old self.
During season 2, he uses a Narukami deck, focusing on Dragonic Kaiser Vermillion as his ace to attack his opponent's front units thus lowering their attack force.This also helps to power-up his rear-guards like his wyvern units and he include Garuda to unflip his damage in order to reuse Dragonic Kaiser Vermillion effect.
Kai later uses Dragonic Kaiser Vermillion "THE BLOOD" ,with an almost the same deck strategy, to defeat Leon in order to send him back to Earth, but was not able to do so. His deck now includes Dragon Monk, Ginkaku to increase his damage when he is at three allowing him to use Dragonic Kaiser Vermillion limit break early and has Garuda to unflip the damge for Dragonic Kaiser Vermillion "THE BLOOD" to strike down the front row with an extra critical.
Kai continues to use the Narukami clan utilizing the Eradicators with his deck. This deck utilizes Vowing Sword Dragon 's effect to get rid of an important threat before going in for the win. In addition, he uses Dragonic Descendant with such an effect to ensure that even when his attack doesn't go through the first time, he sets up for another, even more powerful strike.It should be noted that while he does primarily use the Narukami clan at this point, he still keeps his unsealed Kagero clan though Morikawa and later Miwa would use this deck.
Link Joker Deck
When he gets Reversed by Takuto, Kai switches to a Link Joker deck that uses the Star-vaders as the main focus and Star-vader, Nebula Lord Dragon as the trump card. His winning image so far is to lock his opponent's rear-guards, cutting off intercepts, locking off boosters, etc., and overwhelm his opponent with it, made easier by the units that gain power through Lock.
Later he refocuses his deck on Star-vader, Chaos Breaker Dragon which utilizes characteristics from both his Narukami and Kagero clans where, after he Locks units, he can force his opponents to retire those Locked units to not only prevent intercepts and boosts, but also building his own defenses by drawing cards by activating this effect.
"Reverse" Kagero Deck
For his fight against Ren, he changes back to the Kagero deck utilizing his original ace card, Dragonic Overlord. However, he now possesses a new unit, one that Takuto wasn't even aware of, the Cross Ride Dragonic Overlord "The Яe-birth" and dedicates his turn entirely on Overlord as the price to restand him is to lock all five rear-guards during the main phase but also gives him a 10000 power increase for it. This give him at least two attacks regardless of whether or not his opponent guards as they have to guard two extremely powerful attacks at full strength. Adding in the reborn Dragonic Overlord Break Ride and now he comes at the opponent's units with an extra 10000 and will likely take out a rear-guard with this power.
Royal Paladin Seeker
In order to find out what happened to Aichi, Kai decided to use a Royal Paladin deck based on the Seekers archetype. Using Seeker, Sacred Wingal's Legion, Kai not only can send triggers back to his deck but also searching Blaster Blade Seeker to activate the Legion attack. Upon activating Legion, Kai can superior call another unit to build onto his offense.
Kai later changes his deck based on Seeker, Thing Saver Dragon as his main ace card who also Legions with Blaster Blade. With it, he can superior ride another copy from the deck and Legion Mate with a Blaster Blade Seeker from the soul to have the Legion attack once more.
Kagero Perdition Dragons
After losing Blaster Blade Seeker and learning that he has to be himself, Kai returns to using the Kagero clan, this time focusing on the Perdition sub-clan. This Deck's play style is to retire units in the same columns to overwhelm his opponents and using his new ace, Perdition Dragon, Vortex Dragonewt, to not only gain power when a unit is retired but also using the Legion skill to retire any 2 units and deal 1 damage to his opponent and nullifying any trigger effects in the resulting damage check, granting the Legion a starting 26000 power without any boosts or additional abilities as a result to commence his attack with.
As of Episode 192, Kai included Perdition Emperor Dragon, Dragonic Overlord the Great in his Deck, whose ability to restand allows him to dish out dangerous attacks that are sure to kill at least one of his opponent's rearguards.
During the movie, Kai uses back his Kagero deck that seems to be a mix of his 1st season deck with his 4th season deck. The deck uses a lot of old cards like Embodiment of Armor, Bahr, Dragon Knight, Nehalem, Burning Horn Dragon and his non-Perdition trigger units, the only Perdition units he used in the movie are Perdition Imperial Dragon, Dragonic Overlord the Great, Perdition Dragon, Dragonic Neoflame and Perdition Mage, Asticah.
Despite being a mix, the deck focuses on his Ace - Perdition Imperial Dragon, Dragonic Overlord the Great since they don't require Perdition unit as cost for their effect to be use. Although not much of Kai's fights were seen it can be interpreted that Kai focuses on overwhelming the opponent with the Greats re-standing ability rather than retiring their rear-guards.
- (EN): Ride the Vanguard! Burn everything in this world to ash with your apocalyptic fire! Dragonic Overlord!
- (EN): Lord of Destruction rising through sacrifice... Fly and set yourself upon my enemy! Blazing Flare Dragon! Superior Ride!
- (EN): Knights of the white light, please show him the way. See the King as he once was! I Ride the Vanguard! Alfred Early!
- (JP): At the end of an endless quest, you arrive at final evolution! Sublimate your savage soul and show your true form! Crossride! Dragonic Overlord the End!
- (EN): Harbinger of destruction, spread your ravaging flames across this battlefield! And rise from the ashes....the Overlord has reached his ultimate form!! Crossride! Dragonic Overlord the End!
- (JP): Ride the Vanguard! Break the cage that seals you and descend to the field! Incarnation of the thunder! Dragonic Kaiser Vermillion!
- (EN): Break through the cage that inseals you! Incarnation of Thunder! Ride! Dragonic Kaiser Vermillion!
- (EN): Now I Ride the Vanguard! The time has come to break through his cage and release the Incarnation of Thunder! Dragonic Kaiser Vermillion!
- (JP): Crossride the Vanguard! A silver sword on white wings! Heavenly Dragon! Dragonic Kaiser Vermillion "THE BLOOD"!
- (EN): I Crossride the Vanguard! White wings and a silver sword! This is the ultimate form of Dragonic Kaiser Vermillion "THE BLOOD"!
- (JP): Ride the Vanguard! Hot-blooded, scarlet dragon... Eradicator, Vowing Sword Dragon!
- (EN): I Ride the Vanguard! Crimson Dragon of Vengeance! Eradicator, Vowing Sword Dragon!
- (JP): Powerful, ancient dragon, trace the ancestry of your form and strength and swoop down the Earth again! Break Ride! Eradicator, Dragonic Descendant!
- (EN): Great Dragon of Ancient Glory. Let your prescence be known! As you crash onto this battlefield! With a Breakride! Eradicator, Dragonic Descendant!
- (JP): Ride the Vanguard! The black and white link, Star-vader, Infinite Zero Dragon!
- (JP): Beast of war arriving from another world, seal the power of their entire army! Break Ride! Star-vader, Infinite Zero Dragon!
- (EN): Slash through their hope with the pain of cursed memories! Fill this battlefield with darkness as a side of what's to come! Breakride! Star-vader, Chaos Breaker Dragon!
- (JP): Slash through everything with your cursed blade and cover the world with the darkness of death! Break ride! Star-vader, Chaos Breaker Dragon!
- (JP): Roar that shatters both good and evil! Fangs that cut through light and darkness! Absolute dragon, everything grovels before you! Break Ride! Star-vader, Chaos Breaker Dragon!
- (JP): Amid the flames of purgatory that reduce everything to ashes, rise from the dead again! Resurrection! Strongest flame dragon! Crossbreak ride! Dragonic Overlord "The Яe-birth"!
- (JP) One ray of light, extending out into the despair of oblivion. The light is courage that connects me and my mate in the darkness. And its name...is Legion! Seek the mate!
- (JP): Stand up, my avatar! The true friend within my soul... my mate! Ride the Vanguard! Blaster Blade Seeker!
- (JP): Open, haloed gate! Silver wings, fly down! Ride the Vanguard! Seeker, Sing Saver Dragon!
- (JP) The light of courage that connects me and my mate in the darkness! Seek the mate! Friendship is in this hand! Our bond is in this heart! Line up, avatar of my soul. Legion!
- (JP): Lead to destruction with a flaming whirlwind! Ride! Perdition Dragon, Vortex Dragonewt!
- (JP): Explosive flames of destruction that even burn away Hell! Burning Purgatory!
- (JP): Seek the mate! Its roar opens a path where none exists. Those flames burn everything in this world to nothing! Stand in line, purgatory dragons. Legion!
- (JP): Reduce that savage soul to ash with your swirling purgatorial flames! Trinity Crimson Flame!
- (JP): Burn away all sins with the flames of purgatory! Vortex Dragonewt! Seek the mate! That scream opens up a trackless path, and those flames burn away everything in this world! Stand together, purgatorial dragons! Legion!
- (JP): Ring the bell signaling the end of time, envoy from purgatory that will destroy the world! Ride the Vanguard! Perdition Imperial Dragon, Dragonic Overlord the Great!
- (JP): Seek the mate! Your passionate heart bursts blindingly into flames. Appear, Dragonic Neoflame! Legion!
- (JP): Calamitous flames and a burning soul! Render all walls meaningless that stand before two fiery dragons! Legio attack!
- (JP): You burn in the scorching heat of purgatory, but you're resurrected again and again, emperor dragon! Feel uplifted among the flames, my avatar! Perdition Imperial Dragon, Dragonic Overlord the Great!
- (JP): Seek the mate! Amid the purgatorial flames that consume everything, a new avatar of flames is born! Perdition Dragon, Dragonic Neoflame! Legion!
- Kai is the only member of Team Q4 not to make a physical appearance in the next series, Cardfight!! Vanguard G.
|Record (Season 1)|
|Katsumi Morikawa||1||Win (x2)|
|Team Chemistry Club Member||18||Win|
|Tetsu Shinjou (Flashback)||49||Win|
|Ren Suzugamori (Flashback)||49||Lose|
|Record (Season 2)|
|Team Movie Star member||79||Win|
|Taishi Miwa||85||Win Several|
|Record (Season 3)|
|Yuta Izaki (Flashback)||121||Undetermined|
|Takuto Tatsunagi (Я)||127-128||Unfinished|
|Record (Season 4)|