Syrus Truesdale, known in Japan as Sho Marufuji (丸藤翔, Marufuji Shō), is a former Slifer Red, then Ra Yellow, and now Obelisk Blue student as well as Jaden's best friend. A decent duelist, although hindered by a great deal of self-doubt, Syrus' journey towards strengthening himself provides sharp contrast to the protagonist Jaden's active determination. Syrus is often a "comic relief" character, partially due to him being very nervous a large portion of the time, in sharp contrast to Jaden's optimistic nature.
Syrus' design incorporates multiple layers of clothing and a wide range of expressions. Depicted here is the duelist in full Slifer Red regalia from front, side, and rear alongside views of his head from different angles. Syrus' character design was overseen by Kenichi Hara. His usual outfit consists of the standard Duel Academy uniform with alternating colors over the course of the series. The designs for all three uniforms worn by Syrus are identical in basic makeup. With his red uniform, a yellow shirt is hidden underneath the jacket, whereas with his yellow uniform, this is reversed. With his blue uniform, the shirt is black, and the collar has buttons not present in his other incarnations - similar to Chazz's uniform before he attended North Academy. The blue uniform also has fins in the back similar to his brother's outfit also not on his other uniforms. His blue hair (of a lighter tint than his brother's) is sectioned in three layers, his grey eyes positioned between the three bangs closest to his face and behind a pair of round-lensed glasses. He carries an Academy-issued Duel Disk on his left hand.
Syrus is easily captivated by any woman, real or otherwise, who happens to catch his eye. However, these feelings are superficial as he often moves from one crush to another. His main crush is the Monster Spirit of "Dark Magician Girl". He has also displayed crushes on the cards "Thunder Nyan Nyan", "Maiden in Love" and "Gamble Angel Bunny". In the original version, he ends the majority of his sentences with "suu" (an elision of "desu"). Furthermore, he calls Judai "Aniki," meaning "big brother," while referring to him as "Bro" in the English-language manga. In the English anime, Syrus also refers to Jaden simply as "Jay." In the third season of the original anime, however, Syrus starts to call Jaden by his first name because of Jaden's selfish actions during his duel against Brron, Mad King of Dark World that led to the deaths of Chazz, Alexis, Hassleberry and Atticus. For these transgressions he begins taking on the self-appointed role as an observer of the season's events. However by the end of the third season and the beginning of the fourth his faith in Jaden is restored and he begins to call him "big brother," again. Starting with the third season of the dub, Syrus is able to break the fourth wall. This is shown when he says he's just there for amusement and would never move the plot along, when Jesse and Tyranno are ignoring him when he's tied up, he says "I know I'm not the star but come on, a little respect people" and that he carried Jaden's water for three episodes. He's even admitted that he doesn't move the plot along, and complains that nobody listens to him. Another instance is when they start discussing where Wheeler originally was worked on; Syrus says "Man, that was a weird episode!" When he ran away from Jaden in the third season, he claimed that the Syrus spin-off show had begun. During the episode he spoke as if each of his actions were the next episode in the spin-off. In the Japanese version Sho is voiced by Masami Suzuki. She also voiced Ghost Kotsuzuka, who called Bandit Keith "Aniki" as well. In the English version, Syrus is voiced by Wayne Grayson, who voiced Joey Wheeler in the previous series.
His Japanese given name means "soar" or "fly". His Japanese last name means "Perfect Wisteria", with 丸(maru) meaning round, circle or perfection and 藤(fuji) meaning "Wisteria". His English given name comes from the Persian word Kuros, which means Sun. It could also be a different form of Cyrus, from the Ancient Greek Κυρος (pronounced Kyros), which means "young" or "far-sighted".
Syrus is considered to be the "weaker" younger brother of Zane Truesdale who attends Duel Academy, originally residing in the Slifer Red dormitory along with Chumley Huffington and Jaden Yuki. Syrus has made progress as a duelist throughout the series. From the onset, he faced Jaden in preparation for a tag duel, but, priding himself on finding a way to outdo his roommate, overlooked the abilities of his own cards. It was for this same reason that Zane forbade him from using the "Power Bond" card, for Syrus was unable to cope with its potential drawback. During the second season, Syrus is given an opportunity to advance to Ra Yellow, should he be able to defeat Missy. Feeling that he should not shoulder his brother's legacy, Syrus gives his "Power Bond" card to Chazz Princeton to pass to Jaden before the start of the duel, though Jaden convinces him to put it back in his Deck after the duel. In episode 55, Syrus develops a rivalry with Tyranno Hassleberry over which of the two is better suited to being Jaden's best friend (in the Japanese version, it is over who has the right to call him "big brother"). They constantly argue and fight, prompting their repetitive separation by Alexis Rhodes. By episode 64, their rivalry comes to a temporary halt, when the two duel to settle matters once and for all. Before the last blow is dealt, Tyranno discovers that Syrus went without food or sleep to search for Jaden, who had gone missing since his defeat at the hands of Aster Phoenix. Seeing Syrus' devotion to their friend, he chose not to activate his "Jurassic Impact" card, which would have wiped both players out simultaneously.
During the field trip to Domino City, Syrus teams up with Tyranno in a duel against the first duo of The Light Brigade, Frost and Thunder. Although the two are pinned down by their opponents, who tuned their Decks specifically to combat their cards, they end up pooling their efforts to combine their monsters into "Super Vehicroid Rex Union". Despite their teamwork, however, Frost ends the duel by wiping out all players but himself, and promptly drags them to his master's lair, from where they are transported to KaibaLand as bait for Jaden and Aster by order of Sarina. As he observes his brother's actions following his "rebirth," Syrus notes Zane's newfound disrespect for his own cards and opponents. He dismisses the barbaric persona, refusing to believe that his brother has sunk so low. Determined to bring his brother back to his senses, Syrus acknowledges the inevitability that the two of them will face one another. During the Genex Tournament, Syrus and Zane duel, they are hooked up to electrodes, just as Zane and Mad Dog were in the Underground Duel. Despite his best efforts and Jaden's secret move to place "Power Bond" back into his Deck, Syrus loses, but he does not give up in hoping that his brother can be returned to his former self. Shortly after the beginning of the third year at Duel Academy, Syrus advances to Obelisk Blue. As a result of Survival Duels being called for by Professor Viper, Syrus becomes self-conscious of his worthiness to wear the outfit of the elites, and sets out to prove himself. In the Japanese version, he also wishes to adopt his brother's discarded title, and thus merit the name of "Kaiser Sho" (カイザー翔, Kaizā Shō). Inspired by Jaden's match with Axel Brodie, however, he decides to remain in Ra Yellow, and sets aside his goal for the future. (In the English version he quits the Obelisk Blue dorm stating that Blue wasn't his color and he left Blue to protect Jaden). After Duel Academy is transported to the first alternate dimension, Syrus falls to the Duel Ghouls and becomes one himself. Later, when Jaden and company venture into another alternate dimension to rescue Jesse Anderson, Syrus is the only one of Jaden's closest friends who isn't sacrificed by Brron. After Jaden wins, he verbally attacks Jaden saying he wants nothing to do with him and up leaving him. While separated from the others, Syrus decides to act as an observer, but later reunites with Aster and Zane when Jaden is freed from his possession. After Zane loses to a Yubel-possessed Jesse, Syrus watches Zane die and fade into particles of light before breaking down in tears. In season 4 Syrus advanced to Obelisk Blue again. Syrus later attempts to finish Zane's Duel with Makoto Inotsume after Zane becomes too weak to Duel, but immediately regrets his decision later as he begins to develop the same heart issues as Zane because of his use of the Cyberdark Deck. However, Syrus manages to overcome his problems and defeat Inotsume, thus inheriting Zane's Cyber Dragon Deck later on and promises to improve it. However, he still later falls to Trueman, and is absorbed into the World of Darkness. He is revived after Jaden defeats Nightshroud. Yu-Gi-Oh! 5D In the Yu-Gi-Oh! 5D's dub, Blister mentions Truesdale as one of the duelist he wanted to duel in the Pro League. Whether this was meant to imply Syrus, Zane or both of them is unsure.
In the manga, Syrus is a much better duelist than his anime counterpart, although he is hampered by his desire to not cause pain to his opponents. In the past, he had forfeited a duel when his friend was in tears, despite victory being in his hands, prompting his brother to consider him too kind to be a duelist. Syrus refers to Jaden Yuki as "bro" which is a play off what his use of the term "aniki" in the Japanse version of the anime. Jaden questions why Syrus does despite them not being brothers, and Syrus responds that Jaden reminds him of when his real brother taught him do. This version of Syrus considers this brother's lack of regard for his abilities as something to overcome, rather than proof of his inferiority. He is determined to be acknowledged as a good duelist. He ends up having to face Jaden in a duel in order to stay at the academy, and despite losing, the entire thing was revealed to be a mix-up. It was thought that Syrus had gotten a zero on a test, but it was actually Jaden that had failed. Syrus participates in the tournament to determine who will earn the right to face his brother, and he loses to David Rabb in the preliminaries. Despite this, he makes it to the to eight, but is defeated there by Chazz Princeton, who originally considered Syrus to be weak. Chazz ultimately wins the tournament, and later finds himself paired with Syrus against Jim Crocodile Cook and Axel Brodie in a Tag-Team Duel. Syrus wins them the duel, and he earns Chazz's respect in the process, with Chazz acknowledging Syrus as another rival he'll need to overcome. Syrus in the ending of the manga. Syrus would be matched against Jesse Anderson in the singles matches for the tournament. He gains an early lead, but Jesse defeats him with "The Tripping Mercury" after being briefly possessed by Tragoedia. He witnesses Jaden and Chazz defeat Tragoedia, and watches Jaden's match against Koyo Hibiki years later.
Syrus plays a Vehicroid Deck, featuring cartoonized versions of various vehicles. He combines them using "Power Bond" and "Vehicroid Connection Zone." His Deck also features many cards that focus on preventing damage to his Life Points, such as "Life Force" and "Magic Cylinder." In the fourth season, Syrus inherits Zane's Underworld Deck and combines with his own to form his Cyberoid Deck. This Deck uses "Cyberdark Dragon" as it's main offensive force, and utilizes the myriad effects of the Vehicroids for defensive purpose. He also focuses on swarming removed monsters with "Dimension Fusion."
In the manga, he still plays a Vehicroid Deck, but this one features many Vehicroids that did not appear in the anime.