Cardfight!! Vanguard

After Aichi plays Blaster Blade, he and Kai recall their first meeting. Back then, after seeing a young Aichi beaten up, the young Kai cheered him up by giving him Blaster Blade, and he told Aichi to imagine himself as a strong warrior like the card. With that in mind, Aichi got absorbed into Vanguard, creating his own deck in the hopes of playing against Kai, who had already moved away by then. Back to the game, Aichi deals a bit of damage to Kai, who retaliates with his ace card, Dragonic Overlord. It wipes out Aichi's units and greatly damages him. All seems lost until Aichi draws a "Heal Trigger", which allows Aichi to stay in the game for one last turn. Aichi launches a final attack with Blaster Blade, which breaks through Kai's defenses and deals one more point of damage to Kai, thus giving Aichi the win. A day later, Aichi revisits the card shop. Despite thinking that Kai would not show up after being defeated, Aichi is glad to see that Kai returns.

Aichi's little sister, Emi, is worried by Aichi's different behavior as of late. After school, Emi sees Aichi with Morikawa and Izaki, who want him to go with them to the Card Capital. However, Emi misinterprets the situation as Aichi hanging with the wrong crowd. Concerned for her brother, she secretly follows the trio to the Card Capital. There, Emi is astounded by all the people in the shop, icluding Aichi, Morikawa, and Izaki, playing Vanguard. It is then that the card shop's manager, Shin Nitta, appears and introduces Emi to the world of trading card games. Emi and Shin then observe a cardfight between Aichi and Morikawa. The battle ends with Aichi winning without taking any damage. Watching Aichi play, Emi sees how much her big brother has changed because of Vanguard. And so, she has become supportive of Aichi playing the game.

After taking a look at Aichi's deck, Shin decides to show him "something nice". So, Shin has Aichi battle Misaki, who, despite working at the card shop, has never actually participated in a Vanguard fight before. Nonetheless, after Shin gives Misaki a special deck, she and Aichi begin their cardfight. In the midst of the battle, Misaki shows that she knows more about the game than she lets on as she draws multiple cards and calls her ace card, the Grade 3 CEO Amaterasu. Using the "Twin Drive" ability that Grade 3 cards have, Misaki defeats Aichi. Through this loss, Aichi learns that he has much more to know about Vanguard if he ever wants to play against Kai again.

Aichi goes to the card shop to buy a booster pack in the hopes of getting a Grade 3 card. When he arrives, he sees a grade-school kid, Kamui Katsuragi, convincingly defeating Izaki in a cardfight. Aichi challenges Kamui, but he refuses, noticing that Aichi is not a strong player. Then, after Kamui beats Morikawa in a cardfight, Aichi tries to buy a booster pack. Suddenly, Emi appears, and Kamui immediately falls in love with her. Before Aichi could buy a pack, Emi drags him back home while Kamui looks on, thinking that the two are boyfriend and girlfriend. Later, Aichi buys a booster pack and is pleased to find that the pack contained a Grade 3 card, Solitary Knight, Gancelot. Just then, Kamui shows up and challenges Aichi, demanding to get Emi if he beats him. Although Aichi misunderstands Kamui's intentions, he and Kamui begin their Vanguard fight. Kamui uses powerful cards like Genocide Jack and King of Swords to quickly deal a ton of damage to Aichi, who strikes back by using his newly-acquired Solitary Knight, Gancelot. But in the end, Aichi loses to Kamui after he calls his ace card Asura Kaiser. Afterwards, Emi arrives and tries to get Aichi home, and it is then that Kamui learns that the two are actually siblings. Now, hoping to get closer to Emi, Kamui starts referring to Aichi as his "big brother", although Aichi is not exactly glad about it.

Aichi and his friends decide to go to a different card shop called PSY. There, they try out the shop's special Vanguard Fight Stage. It oddly reacts to Aichi, which leads to a woman, Kourin, challenging him to a cardfight. When the two begin the battle, Aichi is surprised that the stage brings the cards to life. Aichi and Kourin, who both use a Royal Paladin deck, continue their battle, until Aichi makes a bad decision in not guarding one of her Vanguard's attacks, ultimately leading to his defeat. Afterwards, another woman, Suiko, gives Aichi the card The King of Knights, Alfred as a special memento for visiting the card shop. Later, Aichi learns from Morikawa that the card shop they visited has disappeared.

Shin introduces the "Standing Fight Table (Name Subject To Change)" to enrich the experience of a Vanguard fight, with Morikawa and Kamui being the first to play on it. After Kamui once again beats Morikawa, Aichi and his friends return to their homes but then see Kai walking back to his home. Wanting to learn where Kai lives, Aichi, Kamui, and Miwa try to follow him, but Kai soon notices them tailing him. Aichi apologizes and tries to get Kai to battle him again, but he declines. However, Kamui challenges Kai, and he reluctantly accepts. The next day, the two commence their cardfight. Kai gains the upper hand by getting a Grade 3 card, Embodiment of Victory, Aleph, into play before Kamui, who counterattacks with his own Grade 3 unit Mr. Invincible. But Kai soon summons another Grade 3 unit Vortex Dragon, and he later activates its Soul Blast skill to destroy some of Kamui's units, leaving Kamui unable to defend himself from Kai's final attacks. Kai defeats Kamui and takes his leave, but not before Aichi tells him that he'll become a stronger and more worthy opponent for him.

The Card Capital Shop Tournament begins soon, but Aichi is hesitant to play in it, even after making a new deck. However, when he learns that Kai will be in the tournament, Aichi decides to enter as well. But when he submits his entry application form, another Vanguard player, Osamu Kishida, places his application at nearly the same time as Aichi. Both of them want to enter, but there is only one open spot left in the tournament. To resolve this issue, Shin recommends to have Aichi and Osamu play against each other to see who gets the last entry spot. Using his Megacolony units' effects, Osamu restricts Aichi's units from standing while scoffing at him for calling so many weak units. However, Aichi uses his new card The King of Knights, Alfred, whose power is increased by the number of other Royal Paladins in play. With Alfred, Aichi defeats Osamu and is therefore officially in the tournament.

The Card Capital Shop Tournament finally begins. In the first round, Aichi must play against Izaki while at the same time, Morikawa battles Misaki. Since this is his first time in a tournament, Aichi grows nervous. His tournament jitters get the better of him as he makes many amateur mistakes. But when he sees that Izaki is also just as nervous and makes similar mistakes, Aichi realizes that he's not alone, regains his composure, and remembers that Vanguard fights should be fun. When he tells Izaki that, he too calms down, and the two continue playing the game at their best. In the end, not only does Aichi win, but Misaki also advances to the next round.

Kamui and Kai advance to the second round of the tournament, along with Ninja Master M, an eccentric player who dresses and acts like a ninja. He meets Aichi, who deduces that he is actually his teacher Mark Whiting, but he denies that claim (even though it's true). The tournament progresses to the second round matches with Aichi facing off against Ninja Master M while Kai plays against the previous tournament's champion Kazuki Inaba. Ninja Master M uses his Nubatama ninja units' effects to deplete the cards in Aichi's hands. He drives Aichi to a corner when he rides his ace card Stealth Dragon Voidmaster and leaves only one card in Aichi's hand. While this is going on, Kai defeats Inaba in his match.

Aichi makes a comeback by calling more units from his deck to boost the power of The King of Knights, Alfred, forcing Ninja Master M to use most of his cards to guard against his attacks. As a result, M is left with no cards to defend himself from Aichi's last attack. Aichi wins and therefore advances to the semifinals. Ninja Master M disappears, and Mark soon arrives (with a bag containing his Ninja Master M attire). After Aichi's match, Kamui and Misaki play in their respective cardfights, and they both advance as well. Before the start of the semifinals, the tournament is put on hold for a lunch break. So, Aichi and Emi have lunch outside the card shop where Kamui tries to get Emi to feed him, but no such luck. After everyone returns to the shop, Aichi, Misaki, Kamui, and Kai all draw lots to determine who will be playing against who. Aichi is put up against Kamui while Kai must fight Misaki. With the matchups set, the semifinals begin.