Kagemaru Kagemaru 「 影丸 」 is the main antagonist of the first season of " Yu - Gi - Oh ! GX " , as well as founder and former chairman of Duel Academy . Etymology . The " Kage " portion of his name is derived from the Japanese word " kage " 「 影 」 , meaning " shadow , " while the " maru " portion means " circle " or " perfection " . Therefore , this character ' s name could mean " shadow perfection " . Another interpretation is " shadow of perfection , " perhaps referring to his failed attempt at becoming immortal , or perfect . " Maru " is also a common end for male Japanese names . Biography . History . Kagemaru was the leader of the Shadow Riders and at some point in the past , a former chairman and creator of Duel Academy . His Shadow Charm was a small ring . In horrible health , he hoped to attain eternal youth by sacrificing Duel Monster Spirits to the Sacred Beast s , gathering the Seven Stars to help him accomplish that purpose . Shadow Riders . He was first involved in the series as an unseen figure talking to Professor Banner through his computer screen , telling him that it was an appropriate time to test Jaden in the Gravekeepers world . Banner argued Jaden might not be ready , but Kagemaru said it mattered not , and he simply would have no use if he failed . He is next seen with the Shadow Riders , asking which one would make the first move , with Nightshroud revealing he would act . After Dr . Crowler loses to Camula , he appears on a screen in Chancellor Sheppard ' s office , taunting him that two keys have already been lost , and wondering if anymore students would fall to the vampire . In Titan ' s flashback in how he escaped the World of Darkness , Kagemaru was shown reaching out to him giving him his item , and promising him freedom if he would serve him and defeat the key holders . After the seventh Rider , Amnael falls , he finally makes his existence known to Jaden and the others , being air - lifted in via helicopter , in his stasis tube . In the original , he said that he created Duel Academy to have a space full of the fighting spirits of duelists to revive the 3 Sacred Beasts . Many students challenge him to a fight , however he only accepts a Duel with one student - Jaden . During the Duel , He Summons all three Sacred Beast s , and they gradually absorb duel spirits which eventually restores him to a muscular much younger form . Jaden struggles against the Sacred Beasts , but ultimately manages to come out on top . After being defeated , he returned to his aged state , and promised to renounce his former ways and asked for forgiveness , which Jaden was happy to give . Kagemaru was then carried to the hospital via helicopter after Jaden accidentally crushed his spine with a bear hug . Darkness . Kagemaru returns to Duel Academy with Sartorius to tell Jaden that they have both had some sort of premonition , feeling that Duel Academy might be in grave danger , theorizing that the Sacred Beasts , Light of Destruction , and Yubel incidents might be related . Both Kagemaru and Sartorius are later present at Jaden ' s graduation ceremony . Non - canon appearances . In " Yu - Gi - Oh ! GX Tag Force " he serves as the final boss of the game , and the player is forced to duel him twice in a row , once in his older , machine - bound form and again in his youthful form . After completing the game , he can also be found during part 1 on the cliff after 10 : 00 PM . Upon acquiring his Deck Recipe s , he also gifts the player with a " Phantasmal Martyrs " card . Deck . Kagemaru plays a " Sacred Beast " Deck revolved .