|“||Just give it some time. Trust me. When I started dueling in the underground, felt the same way. But then I discovered the pleasure of pain. Duels aren't all fun and games. They hurt! They're about enduring anguish and making your opponent suffer!||„|
|~ Zane's opinion on dueling after his change of heart.|
Ryo Marufuji, also known as Zane Truesdale, is a supporting character in Yu-Gi-Oh! GX. Though he at first serves as a supporting character, during the second season he becomes a villain after experiencing a transformation of mind, becoming much more brutal and sadistic, though he is later redeemed in the third season.
He was voiced by Takeshi Maeda in the Japanese version, and by Scottie Ray and Andrew Rannells as a child in the English version.
Zane is pitted against Mad Dog in the "Underground Duel," a competition in front of a shady audience wherein both contestants are sealed inside a cage and forced to wear electrodes that shock them each time life points are depleted. Zane finds himself on the losing end again but realizes that his former philosophy of respecting the opponent above the desire to win has limits towards the end of the game. Frustrated and desperate, he resorts to cruelty and aggression and summons the "Chimeratech Overdragon", which wins the duel and practically destroys the dueling ring in the process. As the smoke clears, Mr. Shroud calls Zane a monster (he is amazed in the 4Kids dub). The next time Zane is seen, he proves his strength to the dueling world once more. He is now addressed as "Hell Kaiser Ryo" in the Japanese version. He has donned a dark outfit, and a personality to match. In English Yu-Gi-Oh! video games, this version of Zane is referred to as "Dark Zane" to differentiate him from his former persona, as both versions are possible opponents.
Zane returns to the Pro League and goes on a new winning streak and many of his opponents are left seriously injured at the hands of his monsters' direct attacks. In episode 83, Zane fires his promoter Shroud and travels into the mountains to confront Shepperd in the dojo where he was brought up dueling, hoping to acquire the forbidden Cyber Style Reverse (サイバー流裏, Saibā Ryū Ura) Deck that existed opposite of his own "Cyber Dragon" Deck. Although Shepperd manages to keep Zane at bay with his "Cyber Ogre" and various methods of manipulating his opponent's monsters, he is defeated by his own "Cyber Ogre 2" when Zane betrays his "Cyber End Dragon." Zane takes his prize but Shepperd believes that he will regain the respect he once held for his opponents during the Genex Tournament so gives him a medal that allows him to participate.
Upon returning to Duel Academy to oversee the Genex Tournament, Sheppard tells Zane's old friend, Atticus Rhodes, that Zane is no longer himself and has been controlled by darkness. Atticus confronts Zane in a Duel but Zane's new Cyber Style Reverse Deck overwhelms Atticus, eventually forcing him to give into the darkness and use his Nightshroud persona. Atticus believes that he will set the darkness free from Zane by defeating him but Zane wins and reveals that he still has complete control over himself and is not being controlled or influenced by darkness like many characters think. He simply changed his personality because he felt like being cruel and ruthless was the only way he could begin winning his duels again.
In Episode 95, Zane approaches Aster Phoenix for a second duel. Syrus, however, intervenes and demands to be his opponent instead. Similar to his Duel with Mad Dog Inukai, both players wear electrodes and are subject to the intense physical punishment of an Underground Duel. It becomes clear that, in his current mindset, Zane spares no one; he is cold, merciless, and sadistic, regardless of whom his opponents are and enjoys witnessing others suffer, even if it is his younger brother he is torturing. Despite Syrus' impressive plays, Zane defeats him when he defuses "Armored Black Dragon - Cyber Dark Dragon" back to its three original fusion components. He then makes his exit, saying that if there is anything he respects at all anymore it is only victory itself. He appears again in episode 102 following a brief run-in with the disguised Blair Flannigan, giving her his tournament medal as he is no longer interested in participating and leaves Duel Academy Island. Every single character that met him on the island is shocked by his change, including Aster. Up to this point, Jaden was also revealed to have thought that Zane had just "tried on a new look".
He is not seen again until midway through the third year when he returns to duel Jesse Anderson to supply the energy necessary for the awakening of "Ultimate Gem God - Rainbow Dragon." Later, after hearing about Yubel, he designates it as his final opponent. Soon after, along with Edo Phoenix, he sees Judai and company off on their journey to rescue Jesse Anderson in the different dimension, only to get sucked in as well with Aster. By this time, it is believed that prolonged usage of electrodes (later revealed to actually be his Underworld Deck) has left him with fatal heart conditions. In the 4Kids dub, he says that his heart is weak from the electrodes but he never says that his heart condition is fatal (although it is heavily implied).
While in the alternate dimension, along with Aster, he helps Jim Crocodile Cook and Axel Broadie in their effort to defeat the Supreme King after he possesses Jaden. After this task, he decides to restore a traumatized Jaden back to his old self but is unsuccessful as he didn't understand the extent of the trauma that being possessed had done to Jaden's psyche. He decides to duel a Yubel-possessed Jesse in order to fulfill his dying wish of being immortalized but is defeated and dies from his heart conditions. However, he manages to grant his wish by making his "Cyber End Dragon" an eternal symbol of his skill and strength. Zane's performance in the Duel and last words along with the wisdom of the others allows Jaden to put his problems aside so that he may face Yubel.
Under unexplained circumstances, he returns to Duel Academy after washing up, unconscious, on the beach, with no explanation given to how he survived his heart failing. His heart is still in bad shape but he is put under the care of his brother to recover. It is revealed that his heart condition was caused not by the electrodes but by his Cyberdark Deck. Zane also appears to have a gentler personality than before as he shows care and appreciation for those around him once again. He later duels Makoto Inotsume, a practitioner of the Psycho-Style, who has made it his goal to destroy all those who use the Cyber-Style. The duel takes its toll on Zane, as he becomes so weak that he cannot even reach to his own Deck to surrender. Syrus attempts to do it for him, then announces that his brother will not surrender but will merely pull out of the duel. Syrus then takes his brother's Duel Disk to finish the duel himself but comes to regret his decision as he starts to suffer the same heart problems as Zane, where the Deck attempts to inflict damage more quickly on Syrus due to the cards realizing that Zane will no longer use them. Syrus overcomes this by "making the Deck his own" by combining it with aspects of his own "Vehicroid" Deck. After the Duel with Inotsume, Zane allows Syrus to keep the Deck with him saying he will start over with a new Deck. He also wants to create a new pro league name as a tag team partner with his brother Syrus.
Before his defeat by Aster, Zane is stern but respectful for his brother, Syrus and his rival, Jaden. He respected his opponents while he duels.
After his defeat by Aster and suffered pain and agony from electrodes of an underworld duel, Zane became a sinister and sadistic enjoying inflicting pain against his opponents. He believing respecting his opponents is weak. He is insanely intelligence of his opponent's dueling style such as Syrus's risky and price abilities.
In spite of his previously ruthless, Zane is still shown to be respectful as he spares Sheppard for the Cyberdark cards. He give away his medal to Blair as he is no longer interested of the GX tournament anymore. In his duel against Yubel, he revealed he cared for his brother.