Serena

Serena (セレナ) is a character in the Yu-Gi-Oh! ARC-V anime. She is the Fusion Dimension counterpart of Yuzu Hīragi (from the Standard Dimension), Ruri Kurosaki (from the Xyz Dimension), and Rin (from the Synchro Dimension). Serena initially thought that fighting for Academia was justice. However, upon meeting Yuzu Hīragi, her judgement has changed. She is one of the Lancers, despite her original origins.

Appearance
Like Yūya and his three counterparts, Serena and Yuzu share the same eye shapes and similar hairstyles. She has green eyes and purple hair which is held back with a yellow ribbon into a single ponytail. She has three purple bangs, one on each side of her face and in the middle. In a similar manner to Yuzu, Serena has two blue, long bangs hanging from either side of her head. She wears a black, open-chest shirt and shorts, both tucked into her red skirt. Underneath her shirt she wears a maroon, turtle-neck shirt. Her skirt is held up by a brown belt, which is connected to a white ring and strapped over her right shoulder. Over her garments, Serena has an open, red jacket with a green and yellow star emblem on either sleeves. The jacket resembles the Slifer Red jacket worn by students in Academia. She wears brown boots with a buckle and a matching glove. She, too, is in the possession of a bracelet.

She later switches clothes with Yuzu, but she retains her bracelet, hair ribbon, and Duel Disk. During the third arc, Serena changes clothes again, this time to a more casual outfit resembling her Academia uniform, with a simple red jacket, large grey shorts, a black vest that is half unzipped over a white shirt, and large brown shoes.

Personality
Serena is often trying to impress the Professor so she can join the war with the Xyz Dimension. She traveled to the Standard Dimension to eliminate the Xyz remnant in order to prove that she was ready and willing. Serena is also strong-willed and determined to get her way, even by being immoral. In a similar manner to Shun, she would attack random people of a certain characteristic (in this case Xyz users) to achieve her goal. While wanting respect, Serena is rude to others and often self-centered on her own goals and actions while ignoring others'.

Although she is proud to serve Academia and initially believed that what they are doing is right, she was shocked to learn the truth from Shun about how immoral Academia was when they invaded the Xyz Dimension, attacking defenseless citizens and laughing in joy at their suffering, treating it all as a simple game.

Etymology
She has also been referred to as "Serena", which comes from the Latin serēnus, meaning "clear, tranquil, or serene". It can also be derived of Mare Serenitatis ("Sea of Serenity"), which is a lunar mare located to the east of Mare Imbrium on the Moon. She has also been refered to as "Selena" (possibly due to the "L"/"R" confusion that is common in Japanese-English translations). It is a common American and Greek name derived from the Greek Selene referring to the Goddess of the Moon in Greek Mythology. This is fitting given that she uses a Deck themed around the moon in the anime.

Past
Three years prior to being introduced to the storyline, Serena was trying to escape Academia to join the war against the Xyz Dimension. She was being chased by facility members and was forced to battle them. During the Duel, Reiji Akaba intervened and help her escape. They continued to run to the harbor until Serena stopped and questioned Reiji, discovering that he wasn't from Academia. At this point, Reo Akaba appeared with several Obelisk Force members who proceeded to apprehend Serena. They carried her away while she kicked and yelled to try and free herself.

Round 1
Outside the room where Sora Shiun'in was being sedated, Serena was secretly listening to the struggling boy's shouts. She smiled upon hearing his claim of eradicating every Xyz user. She decided that would eradicate the Xyz remanding to prove her strength to the Professor. As Serena was leaving for the Standard Dimension, Barrett stated that he would go along with her.

Round 2
They watched Hokuto Shijima win his match and walked away, though spotted by Ayu Ayukawa. She proceeded to defeat Hokuto and turned him into a card. As she approached Yū Sakuragi, Reiji Akaba intervened. Serena threatened to Duel Reiji if he were to get in her way but was stopped by Barrett. Barrett challenged Reiji to a Duel and lost while Serena spectated. Afterwards, Barrett teleported back to Academia while Serena continued her mission. As she started to leave, Reiji stopped her and offered her an alliance to defeat Reo.

Battle Royal
Serena rejected it and continued outside the Maiami Championship and watched as the city was turned into a field for the remaining 16 competitors, commenting that the remaining Xyz remnant must before in there.

Serena wandered around in the Jungle Area when she saw Dennis Macfield using an Xyz monster and headed towards the Volcano Area. She arrived and challenged Dennis while Yuzu's Hīragi watched. She defeated Dennis when he was distracted by the arrival of the Obelisk Force members who were trying to capture her and Yuzu. However, they were saved by Hikage and Tsukikage and the Lancers.

Hikage and Tsukikage left them in the Iceberg Area where she was questioned by Yuzu. Serena proceeded to explain the Professor's ambitions and goals: To unite all the dimensions into one world. Yuzu claimed that the Academia invaders had hunted down the people of the Xyz Dimension as if it were a game, which Serena denied. Serena claimed that Academia's soldiers were prideful, and that the Xyz Duelists should also be prideful and should also be willing to accept defeat. Yuzu pointed out that the Xyz Duelists' families were affected too, and pointed out Shun and Ruri as an example, stating that Shun was fighting Academia to get her back. Yuzu's continued on to suggest that Serena confirm this and find Shun herself. Serena agreed and switched clothes with each other. They decided that Yuzu would distract the Obelisk Force members while Serena headed towards the Ancient Ruins Area to find Shun. The two agreed and parted ways. Serena arrived at the Ancient Ruins Area to find Sora Dueling Shun. Sora proceeded to defeat Shun, who flew past Serena and down the steps, wounded. Serena helped Shun escape from Sora by using "Lunar Eclipse" to veil the Ancient Ruins Area in darkness. Serena and Shun fled into the Volcano Area where she once again received assistance from Hikage and Tsukikage. They continued to run until they were stopped by Obelisk Force members and were challenged to a Duel.

When Serena tried to take her turn, she tried to counterattack with her ace, "Moonlight Cat Dancer". However, since her Deck was well known with the Obelisk Force, and they dismantled her attack. Serena witnessed the arrival and subsequent defeat and sealing of Michio Mokota and Teppei Tairyobata  and Shingo's rescue of Tsukikage. With the combined effort of Shingo, Gongenzaka and Shun, they were able to defeat the Obelisk Force. Afterwards, she went to Sora and Yūya's Duel, where it ended without a result as the Battle Royal timer had run out. After Mieru mistook her as Yuzu after Gongenzaka had made the initial mistake in the Duel, she clarified that she was not Yuzu. Serena then watched as Sora escaped back to the Fusion Dimension. Reiji showed up and informed the group along with Shingo that they passed the Battle Royal Test of becoming Lancers. Serena also noticed an upset Yūya next to her, due to Yuzu's disappearance. When Yūya blamed Reiji for what happened, Serena said that if anyone was to blamed for Yuzu's disappearance, it should be her. Serena revealed that she was an Academia Duelist, earning her suspicion from Shingo who accused her as a spy, but she further revealed that the reason for the Obelisk Force's arrival was to take her back to the Academia and assumed that they mistook Yuzu as her. She explained that she swapped clothes with Yuzu so she could meet Shun while Yuzu used herself as bait to turn the Obelisk Force's attention away from Serena, much to Yūya's dismay. As Reiji's and Yūya's Duel started, she began a conversation with Shun to confirm Yuzu's story behind the Xyz Dimension tragedy, also revealing to Shun why she had come to Standard. Shun confirmed the story and told Serena the horrors done to the Xyz Dimension, the effects that it had on him, and Ruri's abduction, which visibly shook Serena as she had believed that her Academia comrades fought with pride and honor. She was further shocked when Shun wondered why she also resembled his sister, Ruri.

Synchro Arc
After Reiji defeated Yūya, she was present at the stadium along with the other Battle Royale survivors when Himika Akaba announced the cancellation of Maiami Championship and the existence of Fusion Dimension to the world. Serena later returned Yuzu's clothes to Yūya, promising that if Yuzu was indeed taken by Academia, she would assist in saving her as one of the Lancers, since she was partly responsible for what happened to Yuzu.