Yu-Gi-Oh! ARC-V (Season 1)

Standard Dimension Arc is the first story arc of Yu-Gi-Oh! ARC-V anime series. It follows Yūya Sakaki from You Show Duel School who discovered a new summoning mechanic called Pendulum Summon, working hard to develop the new summoning method and become a professional Entertainment Duelist by participating in Maiami Championship. In the midst of this, he and his friends started to learn of the existence of other dimensions and got involved into inter dimensional warfare.

Discovery of Pendulum Summon
Yūya was training at You Show Duel School with his childhood friend Noboru Gongenzaka, which got terminated when his another childhood friend, Yuzu Hīragi, accidentally broke the Solid Vision system. He was then called out by his friends and teacher, Shūzō Hīragi for his nonchalant and goofy attitude and told him of their expectation as his father's son, but Yūya simply brushed them off. Yūya was then visited by Nico Smiley who offered him a chance to Duel the current Duel Champion, Strong Ishijima. This initially upset Yūya since it reminded him of his father's, Yūshō Sakaki's, disappearance on the day his father was supposed to Duel Ishijima, and was deemed a coward who ran away by others as the result. But Yūya eventually agreed so he can clear his father's name. On the day of the Duel, Yūya put up a good performance for the half of the Duel until Ishijima managed to counter Yūya's play, pushing Yūya to a corner and making him lose hope until he remembered his father's words, regaining the courage to continue. Suddenly, his pendant reacted with three of his Effect Monsters - "Stargazer Magician", "Timegazer Magician" and "Odd-Eyes Dragon", transforming them into Pendulum Monsters, while "Odd-Eyes Dragon" was transformed into "Odd-Eyes Pendulum Dragon". Using his his new monsters to support "Odd-Eyes Pendulum Dragon," he wiped out Ishijima in a single attack, winning the Duel. Afterwards, he was swarmed by people asking about the Pendulum Summon that he'd performed, though he seemed unaware of the details himself and didn't seem to remember exactly what had happened. Yūya initially got a warm reception until he discovered that Pendulum Summon can only be performed by using Pendulum Monsters that only he has, leading people who initially wanted to apply to You Show Duel School to think that Yūya was cheating when Dueling Ishijima and left. However, one boy, Tatsuya Yamashiro, still decided to apply out of admiration for Yūya. The  Pendulum Summon  that Yūya performed also earned him attentions from several Duelists; The president of  Leo Corporation ,  Reiji Akaba, who since then began to observe him closely: Shingo Sawatari, a student of Leo Duel School (LDS) who once stole his Pendulum Monsters: and Sora Shiun'in, a Fusion user who developed admiration towards Yūya and initially demanded to be made his apprentice until he decided to become a student of You Show Duel School instead.

You Show Duel School vs. LDS
While on their way home from shopping, Yuzu noticed and overheard Shingo wanting to get revenge on Yūya, so she confronted him to teach him a lesson. However, before the two can commence Duel, a mysterious masked Duelist suddenly barged in and took over the Duel in Yuzu's place. The Duelist, an Xyz user, has an ability to produce shockwaves even though they were not on Action Field. He easily defeated Shingo with his ace monster, "Dark Rebellion Xyz Dragon" and was revealed to have identical face with Yūya, leading Yuzu, Shingo, and the others to mistook him as Yūya. The Duelist suddenly disappeared when Yuzu's bracelet suddenly shined just as Yūya arrived, oblivious of what she meant when Yuzu inquired him. Following the incident, Reiji's mother, Himika Akaba, used this as an opportunity to take over You Show Duel School by accusing Yūya as Shingo's attacker based on Shingo and his lackey's exaggerated testimony and Yuzu as the eye witness, though Yuzu decided to trust Yūya in the end. Knowing Himika's real intention to add You Show Duel School to LDS, Yūya and his friends accepted Himika's challenge for a three vs. three Duels. Yūya, Yuzu, and Gongenzaka represented You Show Duel School, while Hokuto Shijima, Masumi Kōtsu, and Yaiba Tōdō represented LDS. The Duel resulted with each school has one win (Yūya vs. Hokuto), one lost (Yuzu vs. Masumi), and one draw (Yaiba vs. Gongenzaka), so Himika proposed a tie breaker Duel between Yūya and Masumi who won their Duels, but instead of Masumi, Reiji took over the Duel against Yūya. Reiji proved to be a formidable opponent for Yūya due to his mastery of all Summoning methods, and to everyone's shock, including Pendulum Summon, though the one that Reiji has was still in development. Just when it seemed Reiji would win the Duel, the Duel came into abrupt stop when Reiji left after he received a report there was another attack on LDS, giving the victory to Yūya.

Reiji's use of Pendulum Summon at first upset Yūya who believed that he was the only one who was supposed able to use it, but after earning a scold from Shūzō in their Duel, Yūya accepted the fact that Pendulum Summon was no longer his and instead he strive to become the best Pendulum user, being its pioneer.

Pre-Maiami Championship
The LDS investigated the attack and received letters containing the attacked people turned into cards. Meanwhile, Yūya remembered that in order to become a professional Duelist, he must enter Maiami Championship. Unfortunately, he couldn't enter the championship as his win rate was only 56% rather than the required sixty. Yūya tried to find four Duelists to Duel all day, but they all refused due to Yūya's victory against Ishijima and mistaken belief that Yūya already got free pass since he has defeated Ishijima. However, Nico then visited him and offer him a free pass to enter the Junior Youth Championship since the Duel Committee has acknowledged Yūya's victory against Ishijima. Yūya declined, however, not wanting to be given special treatment, but he was able to get Nico to set up his next four Duels. Meanwhile, Yuzu asked Sora to teach her Fusion Summon so she can beat Masumi. Sora at first was reluctant, but agreed after seeing how determined she is. While explaining about Fusion Summon, they encountered the black-masked Duelist who was suspected to be the culprit behind the LDS attack. Before he can be questioned, he once again disappeared due to Yuzu's bracelet shined at the same time as Yūya's arrival. Hearing that Yūya will be entering the championship, Sora decided to enter as well, able to participate as long as he defeated six Duelists. As Yūya continued to develop his Pendulum Summon and defeated opponents set by Nico so he can be qualified to enter the championship, he encountered a mysterious Duelist with the same ability as the black-masked to create real shockwave without Action Field when he was chased by LDS people, but he dismissed it as a dream after he got knocked out. LDS finally found the Xyz user who has been attacking LDS Duelists, Shun Kurosaki, who turned out to be closely acquainted with Yūto, the black-masked Duelist that Yuzu met before. From Yūto, Yuzu learned that he and Shun were trying to save Ruri Kurosaki, Shun's younger sister and his dear friend who bears resemblance with Yuzu was kidnapped by Fusion users whom they believed connected with LDS, and Shun has been attacking LDS Duelists to lure out Reiji, which he succeeded after defeating Masumi, Yaiba, and Hokuto.

Opening Ceremony
After qualified to enter the championship, Yūya and there rest of his friends attended the opening ceremony of Maiami Championship. Much to Yūya and Yuzu's shock, Shun also participated representing LDS. When Yuzu questioned Masumi, she revealed that Shun has been one of LDS all along, confusing Yuzu. It's later revealed that Shun and Reiji has formed alliance with each other since they have a common enemy: Reiji's father, Leo Akaba, and Reiji had Masumi, Yaiba, and Hokuto's memories regarding Shun as LDS' attacker erased. After the opening speech, the Duelists' opponents for the first round was announced: Yūya against Shingo, Yuzu against Masumi, Gongenzaka against Gen Ankokuji, and Sora against Shun.

Round 1
Yūya, Yuzu, and Gongenzaka won their respective Duels. When it was Sora's turn to Duel, the initially entertainment Duel soon turned into battlefield as Sora revealed his bloodthirsty nature that he never showed before. Sora also revealed himself to be in league with the group who had destroyed Shun's homeland and kidnapped his younger sister. The Duel ended with Shun's victory, heavily injuring Sora in the process. After the Duel, Yūto visited Sora and questioned about Ruri's whereabout, but Sora didn't know and demanded for Shun's location, refusing to acknowledge his defeat against Shun. He escaped from the hospital to follow Yūto, prompting Yūya, Yuzu, and Gongenzaka to search for him when they heard the news while discussing about Yūto, Shun, and Sora.

Meeting Yūto and Yūgo
Yūya found Sora Duelling against Yūto and joined the Duel after hearing the latter's intention to defeat Sora. During the Duel, he and Yūto felt a throbbing sensation on their chest when they summoned their respective dragons, "Odd-Eyes Pendulum Dragon" and "Dark Rebellion Xyz Dragon", which became stronger when they clashed. The Duel stopped when Sora suddenly disappeared as he revealed his mission. Yūto explained to Yūya that their world is consisted of four dimensions: Fusion Dimension, Xyz Dimension, Synchro Dimension, and Standard Dimension. Yūto and Shun came from Xyz Dimension and were members of Resistance. They were currently at war against Academia, a Duel school from Fusion Dimension who not only have destroyed their homeland but also turned its residents into cards. During their conversation, a Duelist riding a vehicle resembling motorbike named Yūgo suddenly appeared, and he was revealed to also has the same face as both of them. Yūgo challenged Yūto, both accused each other as the one responsible for taking someone precious to them. Similarly as Yūya's Duel against Yūto, the three of them sensed a throbbing sensation when Yūgo summoned his dragon, "Clear Wing Synchro Dragon", and Yūto summoned "Dark Rebellion Xyz Dragon". The summoning of the two dragons completely changed the attitudes of the two Duelists, making them wanting to destroy everything. Yūya came between them in attempt to stop the Duel. While he succeeded in convincing Yūto, Yūgo continued his battle phase, leading Yūto to shield Yūya from the attack that defeated him. When Yūto came to, he entrusted his "Dark Rebellion" and his wish to Yūya. The two of them were surrounded by white light, and when Yuzu arrived, Yūto and Yūgo disappeared and Yūya in daze before he fell unconscious.

Round 2
Regaining his consciousness after two days sleep, Yūya and Yuzu exchanged what they have known so far, and decided to ask Shun about Sora and Academia since he is Yūto's comrade. After watching Yaiba's Duel against Isao Kachidoki who used violence to stop Yaiba from getting Action Card and won, Yūya found that Isao would be his next opponent. In their Duel, Isao's violent method drove Yūya into corner. An abnormality then occurred within Yūya that caused him to saw a vision of Yūto who merged with him in his mind and just as they did, Yūya's personality drastically changed, heartlessly defeating Isao using Yūto's dragon with Yūya himself has no recollection of what he did when the Duel ended. While the championship continued, two Duelists from Academia, Barrett and Serena who bears resemblance with Yuzu, has been attacking and carding any Xyz Duelists they encountered, one of them being Hokuto. Reiji confronted the two of them, facing against Barrett who he defeated. Reiji then questioned Serena's presence in the city was due to Leo's, whom they referred as the Professor, order. Serena denied this, stating she came to defeat the remnant to Xyz Dimension to prove her worth to the Professor who refused to place her in the main force despite her skill. It's revealed that three years ago, Reiji accidentally came to Fusion Dimension while looking for his father and met Serena. Before he was forcefully returned back, Reiji learned of his father's plan to unite the four dimensions.

When Barrett retreated to report to the Professor of their whereabouts, Reiji deduced that Academia forces will come and quickly came up with a plan to face against them in the championship that also served as testing ground to select Duelists who are worthy to become members of group known as Lancers.

Battle Royale
The final stage of the championship is revealed to be a battle royale between the Duelists who have passed the first round. The Action Field will take place in the entire Maiami City and Pendulum cards will be distributed with the Duelists who have gathered the most Pendulum cards declared as the winner. Yūya and Yuzu split up to find Shun, encountering their opponents on their way. Yūya was challenged and cornered by Ken and Makoto who were from the same school as Isao, but he was fortunately saved by LDS exchange student, Dennis Macfield and the two defeated them. At the same time, Yuzu teamed up with Gongenzaka against Olga and Halil after they she and Halil accidentally bumped into them while Dueling against each other. Serena, who thought the Xyz remnant (Shun), was participating in the championship, entered the Action Field as well. Watching the Duel between Yuzu and Dennis, she mistook Dennis as a remnant of Xyz Dimension since he used Xyz Summon and challenged him to a Duel, which Dennis accepted. To avoid further misunderstanding, Dennis purposely didn't perform Xyz Summon, which put him at disadvantage and offended Serena who thought that he was underestimating on her. And just as Dennis decided to get serious, he has unlucky draw, resulting in his defeat. Meanwhile, Sora and Academia's elite force the Obelisk Force infiltrated the championship. Sora challenged Shun for a rematch, while Yūya Duel against the Obelisk Force. After Serena defeated Dennis, she and Serena were approached by the Obelisk Force. Duelists from Fūma Duel School, Hikage and Tsukikage, saved Serena and Yuzu just before Obelisk Force could do anything, leaving them to face Duelists prepared by Reiji. Yuzu told Serena who was unaware of the despair brought by Academia to Xyz Dimension what Academia had actually done. She told Serena to look for Shun to find out the truth, the two swapped clothes so Serena won't be pursued by the Obelisk Force. Unbeknownst to them, Dennis has been observing them and was revealed to be a spy sent by Academia to locate Yuzu, and informed her whereabouts to Yūri, a Academia Duelist who also bears striking resemblance with Yūya. When Olga and Halil ran into them, Yūi saw them as a nuisance and turned them into cards. Yūri approached Yuzu just before the Obelisk Force could attack her, admitting that he was the one responsible for kidnapping Ruri and a girl named Rin, and this time, he was ordered by the Professor to take her to him. Refusing to back down, Yuzu accepted his challenge, but was no match for him and could only delay her defeat by Dueling while finding a way to escape. After defeating the Obelisk Force, Yūya was restrained by Gongenzaka, Michio Mokota, and Teppei Tairyōbata, when he seemed to have lost control of himself. When Mieru Hōchun checked on him with her crystal ball, she found there were two souls within Yūya and pitch black darkness that was trying to consume both souls. After Yūya returned to his senses, he told them of Academia's arrival, and Mieru informed him of the existence of another inside him and a black shadow. When Yūya learned of this after recovering, he realized that the other soul was Yūto while the darkness was what making him Duel violently against Isao and the Obelisk Force. The next day, the group decided to split up to inform the other Duelists of the danger due to Academia's arrival. Yuzu, who was running away from Yūri, met Yūgo who mistook her for Rin that Yūri mentioned before. She and Yūgo got transported elsewhere when Yūya arrived on the scene looking for her with Gongenzaka. At another area, Serena finally found Shun just as he was defeated by Sora and defended him before Sora could turn him into a card. They were assisted by Hikage and Tsukikage who have been hired by Reiji to protect Serena. While Hikage duels Sora, Serena, Tsukikage, and Shun duels the Obelisk Force. Shingo, who felt something was wrong, was allowed by Reiji a second chance to participate in the championship. Yūya and the others arrived as well shortly after the Duel was commenced. Michio, Teppei, and Hikage were defeated and sealed into cards, urging Gongenzaka to assist Serena and the others while Yūya duels Sora. With their teamwork, they were able to defeat the Obelisk Force. Yūya, on the other hand, before their Duel could end, the Action Field was stopped since the battle royal has reached its end, forcing Sora to retreat. Reiji then appeared and explained that the battle royal was a test ground to find Duelists capable to become members of Lancers, a special group that he created for the sake of defeating Academia. Learning that Reiji has deliberately let the participants being carded and concluded that Yuzu also shared the same fate when Serena revealed she switched place with Yuzu, Yūya angrily challenged Reiji to a Duel to make him repent, but was defeated by him.

The Lancers
After the battle royal, Himika and Reiji announced the existence of other dimensions and Academia's invasion, showing some of the footages of what happened during the battle royal when the Academia invaded. Himika urged every Duelists in the world to polish their skill to prepare the incoming invasion by Academia, introducing Yūya and the other survivors of the battle royale for exception of Mieru as the chosen elite Duelists of Lance Defense Soldiers (Lancers) who will go to other dimension to fight against Academia ahead of them.

A day before their departure, Yūya, who was still depressed by Yuzu's disappearance and Sora's betrayal, was forced into a Duel by his mother, Yōko Sakaki, who told him of her first meeting with his father. She reminded Yūya the importance of the philosophy that they were sharing: To bring smile with Duel as she entrusted him with the card that signify her bond with his father, "Smile World". Regaining his resolve, Yūya determined to carry out his Dueling with the philosophy that he believes and save Yuzu.

Departure to Synchro Dimension
The chosen Lancers from the championship: Yūya, Gongenzaka, Dennis, Shingo, Tsukikage, Shun, and Serena gathered at LDS. Reiji also included his younger brother, Reira Akaba, into the team, which initially earned protest from Shun and Shingo due to his young age. Meiji also revealed that they were not going to Fusion Dimension, but to Synchro Dimension to gather allies. After watching Yūgo defeating the Obelisk Force during the battle royal, Reiji was convinced that Synchro is not enemy. Furthermore, Yuzu was seen disappeared with Yūgo, which mean that she must have also in Synchro Dimension as well. Shun at first refused and determined to go to Academia alone, but was convinced by Serena that Ruri will be okay based from the way the Professor treated her. With everyone ready, the Lancers departed to Fusion Dimension.