Characters / Yu-Gi-Oh! GX Teachers

A character subpage from the Yu-Gi-Oh! GX anime and manga series, the Oddly Named Sequel to Yu-Gi-Oh!. For the main character page, see here.

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Teachers

Professor Cronos de Medici (Dr. Vellian Crowler)

Cronos de Medici (クロノス・デ・メディチ) (Vellian Crowler)

The head Obelisk Blue professor at Duel Academy, and initial (albeit non-lethal) antagonist. Looks down upon Osiris/Slifer Red students, particularly Jaden, whom he calls "drop-out boy".

He uses an Ancient Gear Deck.

Voice actor: Hiroshi Shimizu (Japanese) and Sean Schemmel (English)

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• Accent Adaptation: Despite being Italian he’s given a pronounced Mid-Atlantic accent in the dub.
• Advanced Ancient Acropolis: Crowler's Deck is based on this theme. His Ancient Gear monsters are implied to be Lost Technology, and some of his other monsters stem from Classical Mythology, such as the Trojan Horse.
• Agent Peacock: You probably wouldn't be able to tell just by looking at him that a man as foppish as he wields a Deck exclusively loaded with burly, rusted, monstrous machines.
• Ain't Too Proud to Beg: Begs desperately to Aster to get him to show Chazz how to be a pro Duelist in Season 4.
• And Then John Was a Zombie: Temporarily turned into a Duel Ghoul (or Zombie) in Season 3 when Duel Academy was sent to the different dimension by Yubel.
• Anti-Hero: The classic kind. He's cowardly and snobbish, but gradually becomes a better person.
• Armor-Piercing Attack: The main gimmick of the Antique Gear deck is that whenever an Antique Gear monster attacks, the opponent is forbidden from activating any Magic or Trap cards in response, which often ends in a destroyed monster. Antique Gear Golem and Ultimate Antique Gear Golem also have a piercing effect, so the opponent still loses Life Points even if the monster is in Defense Mode.
• As Long as It Sounds Foreign: He says some Italian phrases (and foods) every so often in the original version.
• Badass Teacher:
  • He may seem wimpy, but when push comes to shove (such as when Shadow Riders or Duel Ghouls get involved), he will put his foot down to protect his students and is not to be underestimated.
  • When Bonaparte suggests demolishing the Red dorm, Crowler ends up being their most vocal defender and Duels Bonaparte to keep the dorm intact. Sure, he might have gripes about them being his worst students, but they are still his students, and anyone that wants to mess with them will have to get through him.
• Beauty Equals Goodness: Averted when he was a villain but played straight when he becomes good.
• Butt-Monkey: He's often the butt of many jokes, especially during the first season as a Sadist Teacher. He is however, a lot more respected in the Japanese version.
• Big Bad: 1st half of Season 1.
• Clockwork Creatures: His Ancient Gear Deck.
• Combining Mecha: His Fusion Monsters look like these, being large multi-limbed monstrosities formed out of the components of the smaller machines.
• Cool Teacher: By season 4. He helps Alexis and Chazz find their paths for after they graduate, he even begged Aster to show Chazz how to be a pro Duelist.
• Cowardly Lion: Crowler can come across as a panicky Agent Peacock at times. He ends up Dueling Shadow Rider Camula by accident when he tries to sneak away during the call for volunteers, but leaps forward in fright after backing into Banner (who is also trying to sneak away). Crowler then tries to weasel out of the Duel by saying he was volunteering to go fetch straws for them to decide who should Duel Camula. However, during the Duel itself, he's surprisingly brave and fierce, even when he's been defeated and Camula is about to claim his soul.
• Crippling Overspecialization: His Ancient Gear Deck prevents activation of Magic and Traps when his Ancient Gear monsters attack. Unfortunately for Crowler, this doesn't include Monster Effects, which run rampant in GX and are usually his downfall. His deck is also strongly centered around Ancient Gear Golem. If Golem is destroyed or incapacitated, or if is strategy for summoning it is interrupted, he's usually in big trouble.
• Crouching Moron, Hidden Badass: Despite being used mostly as Plucky Comic Relief after Jaden defeats him in the pilot, he has his moments. He tends to vigorously defend his students when they're in peril, even at great danger to his own life. And when it's time for him to Duel, he always has a way to get his beloved Ancient Gear Golem on the field no matter what his opponents throw at him, at which point it's time to clean house.
• Defrosting Ice King: Towards Jaden. After Jaden defeats him in the pilot episode, Crowler refuses to accept he lost to a slacker and starts plotting against him, in order to get him expelled. However by the end of Season 1, as Crowler begins to grow fond of Jaden and his gang, he saves the Osiris dorm from getting demolished by Bonaprate, and by the end of the series he doesn't want the main cast to graduate and is determined to keep Jaden and his friends at school, and make them repeat their third year.
• Deus Exit Machina: He is without his Deck during the Dimension Arc, and thus can't Duel. This does however, allow him to survive it unscathed.
• Dishing Out Dirt: His Ancient Gear monsters are all EARTH.
• Dude Looks Like a Lady: Though unlike the usual example, he's definitely not the Pretty Boy type. The dub, in particular, had a field day with this, such as Hassleberry referring to him as "ma'am."
  Museum guard #1: I didn't know he was a doctor.
  Museum guard #2: I didn't know he was a dude.
• Evil Is Petty/Sore Loser: His initial antagonism towards Jaden, which varied from attempts at getting him expelled to him going missing or being outright killed (in the dub), was fueled from his anger at not being able to stand the idea that he could lose to a "slacker" like him.
• Explosive Overclocking: The "Limiter Removal" Spell Card doubles all Machine monsters' attack power but destroys them at the end of the turn. Crowler uses Limiter Removal to win his Duel with Chumley by powering up his Ancient Gear Golem so it's stronger than Chumley's Master of Oz. The Golem's being destroyed doesn't matter because it defeating Chumley's monster wipes out his Life Points.
• Expy: Of just about every teacher unfortunate enough to antagonize Yugi and his friends. However, he does become a lot nicer later on. Even though he's not Jaden's rival, he serves as the first Kaiba stand-in of GX, most notable in his Dueling style, with Ancient Gear Golem and Ultimate Ancient Gear Golem in particular being clearly expies of Blue-Eyes White Dragon and its own ultimate form.
• Flanderization: Similar to Kaiba in the previous series, his Jerkass character traits are turned up a notch in the dub, to the point where he makes condescending and rude comments during scenes where he is actually very nice and respectful in the original. Most notably during Chumley's graduation duel, where his lines don't even really fit the animation.
• Gonk: Just because he looks like a lady does not mean he's pretty. After defeating him and turning him into a doll, Camula immediately discarded him over his looks.
• Hate Sink: Initially, Crowler is portrayed as extremely smug, petty, and unreasonable with an irrational hatred toward Jaden, making him very easy to dislike. He eventually mellows out, though.
• Heel–Face Turn: He starts off antagonistic to Jaden, but eventually comes to like and respect him. The point of the turn started during the Shadow Stars arc and continued after then.
• Hidden Depths: He's a very capable Duelist who usually only loses because of the plot and a good enough teacher that even Jaden, who by his own admission sleeps through most classes, has been known to quote his lessons. When he Dueled Chumley, even though Chumley lost, he was impressed enough by Chumley's performance to still recommend him for a job at Industrial Illusions, despite his claim that he would expel him on the spot if he lost.
• Hoist by His Own Petard: In his first duel against Judai, Crowler's strategy to turbo out Ancient Gear Golem required the usage of trap cards that, when destroyed by a card effect (i.e. Heavy Storm), summoned out monsters to be used as Tribute fodder. During his second duel in the series, against Camula, the evil vampire uses this against him, specifically playing a Trap that would activate if Crowler destroyed it, enabling her to bring back one of her monsters, which was then used as part of the Zerg Rush that dealt the finishing blow.
• It's Personal: He's not very fond of the Reds as a whole, but he has it out for Jaden in particular for having the gall to show up late and then humiliate him in a Duel. A big part of his Character Development involves him getting over it.
• Jerkass Has a Point:
  • His personal grudge for Jaden aside, his overall dislike for the Osiris Red students does have valid reasons, since Duel Monsters are Serious Business by their current time and any underperforming student treating it as some run-of-the-mill children's card game where it can be a potential career occupation would be something that Crowler would be intolerant of. His initial dislike of Judai is also based on the latter's cavalier attitude, which actually does cause some serious problems down the road and is called out by others. That being said, the lengths he goes to in attempts to get Jaden expelled and punish him for no reason just come off as extremely petty.
  • When Chumley was offered a card designer job by Maximillian Pegasus himself, Crowler was the only one to deny Chumley his job, not because he hated him, but because he hadn't proven himself yet. Chumley was by all account an average student at best, so to have him immediately leave school just like that would give off a bad reputation to the school, especially when other students have worked even harder than Chumley and are still enrolled. Crowler takes his job as a teacher very seriously and will not give Chumley an easy pass, even if it's from one of the most influential Duel Monster figures in history.
• Jerkass to One: Overall, he doesn't have a good opinion of the Osiris Red students mostly from the result of the elitist dorm system in the Academia and Duel Monsters being Serious Business, but when it comes to Jaden specifically, then Crowler would stop being reasonable altogether and find any excuse to expel the latter. It's only until Character Development to where Crowler starts to let bygones be bygones.
• Jerk with a Heart of Gold: He's very disparaging of Jaden and his friends, calling Jaden "dropout boy" in the original and referring to them collectively as "Slifer slackers" in the dub, but is more than willing to lay his life on the line for his students, even Jaden. As time goes on, he becomes a lot closer to Nice Guy than Jerkass.
• Karmic Butt-Monkey: Anytime Crowler is acting like a jerk, you can expect something bad to happen to him immediately afterward.
• Large Ham: Extremely overdramatic. Just watch the episode where he tries to keep the students from graduating.
• Magic Poker Equation: A bizarre example as this trope completely works against him more often than not. He's obscenely lucky in his starting draws to the point that he'll have the means (of which he has a lot of in his Deck) to summon an Ancient Gear Golem in his first few turns if not the very first. But because this would necessitate a Drama-Preserving Handicap to stop him from winning right away, his opponents will have just the right counters to survive or even neutralize his Golem's attacks. When Crowler finds a way to free his Golem from his opponent's counters, things usually tend to go very badly for them.
• Meaningful Name: His given name is one to the Greek titan, Cronos, which fits well with the overall theme of his Ancient Gear monsters. Also, his surname is one to the Medici family, an Italian noble family who ruled Florence and Tuscany during the Renaissance period.
• Non-Action Big Bad: For the first half of the opening season, he tries various ways and commissions a number of proxies to try to expel Jaden or at the very least make his life at school miserable as he can't do so with a straightforward rematch.
• One-Winged Angel: His Ancient Gear Golem can be fused with two other Ancient Gear monsters (Crowler uses all of his Golems specifically) to create Ultimate Ancient Gear Golem, an even bigger 4400 ATK/3400 DEF behemoth that has all of the Golem's effects, plus one: it revives a Golem to the field if it is destroyed.
• Sadist Teacher: In the first half of season 1, where his story arc consists of him finding various inane excuses to try and get Jaden expelled.
• Signature Mon: Ancient Gear Golem, a 3000 ATK/3000 DEF behemoth that deals damage to Life Points regardless of if the target monster is in Defense Mode or not, in addition to the standard "Ancient Gear" ability to prevent Magic and Trap cards from activating during its attacks. He has three of them and a plethora of ways to summon them.
• Sissy Villain: At least for the first part of the series, where he serves as the main antagonist. After that, he's still effeminate and foppish, but no longer a villain.
• So Proud of You: In season 4 after his rematch with Jaden, he admits that he enjoyed being the teacher of Jaden and the others, and actually sheds Tears of Joy at losing.
• Stern Teacher: He expects his students to do their work, which comes to bite Chumley and Jaden later on.
• They Call Me MISTER Tibbs!: In the dub, where he insists on being called Doctor Crowler. He did not waste nine years of his life getting a PhD in Dueling, thank you very much.
• Token Adult: In Season 3 during the Dimension World arc.
• Took a Level in Kindness: Starts creeping in more and more as the series goes on. At the end of Season 1, despite beating Chumley in their Duel, Crowler expresses genuine admiration for his Dueling skills and allows him to graduate. He also is shown clapping with everyone else after Jaden and Zane tie in their Duel in the first season finale. In Season 2, he goes on to defend the Red dorm (something that would have seemed wildly out of character at the start of the character). By Seasons 3 and 4, he is practically a Nice Guy. Depending on interpretation, he could be seen as always having been a nice guy with some wounded pride over losing to Jaden.
• Tooth Strip: A notable aversion; his teeth are usually drawn distinct from each other. Doesn't exactly help his already odd appearance, especially when he was turned into a doll.
• Trap Master: Crowler's Ancient Gear Engineer monster can No-Sell the opponent's Trap Cards. When it destroys an opponent's monster in battle, it can also destroy an opponent's trap. Crowler uses this in his Duel with Bonaparte to destroy the Gulliver Chain trap preventing his Ancient Gear Golem from attacking.
• Verbal Tic: "Na no ne" in the original Japanese.
• We Can Rebuild Him: Crowler's Ancient Gear Factory card allows him to summon an Ancient Gear monster by banishing Ancient Gear monsters already in his Graveyard instead of Tributing monsters already on the field. His Duel Disk depicts it as building a new Ancient Gear monster from the junk parts of the monsters already in the Graveyard.
• Worf Had the Flu:
  • He loses to Camula due to her using vampire bats to spy on his Deck in order to learn how it works ahead of time. Fortunately her bragging about this allowed Zane and Jaden to work around that.
  • Due to being pulled into the portal only by accidental proximity, he's without his Deck and can't Duel for the latter half of season 3.
• Younger Than They Look: He looks far older than the 35 he actually is.

Kabayama (Professor Sartyr)

Kabayama (樺山) (Sartyr)

The head of the Ra Yellow dorm and unfortunately the least featured of the 3 main professors.

He uses an anime-exclusive spice Deck.

Voiced by: Yuichi Nagashima (Japanese) and Marc Thompson (English)

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• Accent Adaptation: He becomes French in the dub.
• A Day in the Limelight: After barely making any significant appearances throughout season 1, he finally gets an episode focusing on him as well as getting lines and his own Duel.
• The Cameo: Has several throughout the series which is the majority of his screen time.
• Cooking Duel: A literal example where he used his monsters to cook in a card effect.
• Forgettable Character: He puts Bastion to shame on how many people forgot he existed and was a teacher who worked at the Academy.
• Hates Being Alone: His main reason for trying to get the Ra students back to their dorm is because most of his students have graduated to the Obelisk Blue dorm, while Syrus and Hassleberry (who are currently in his dorm) choose to spend their days at the Red dorm instead.
• Hidden Depths: Despite being a teacher at the academy he is an accomplished chef and is skilled card designer.
• Large Ham: Has shades of this especially when he is Curry Mask.
• Out of Focus: Despite being the head of one of the three main dorms, he hardly gets any significant screen time aside from a few cameos.
• Paper-Thin Disguise: Literally. He wears a paper bag over his head to disguise himself.
• Supreme Chef: He is very good at cooking and used his skills to lure the students out of the red dorm.
• Through His Stomach: He uses this tactic in order to try to convince the Ra Yellow students in the Slifer Dorm to come back to Ra Yellow.

Daitokuji Sensei (Professor Lyman Banner)

Daitokuji (大徳寺) (Lyman Banner)

^Amnael

The head of the Osiris/Slifer Red dorm and Alchemy professor and a mentor for Jaden until he's revealed to be The Mole.

He uses an alchemy-themed Deck based on removing monsters from play.

Voiced by: Kappei Yamaguchi (Japanese) and Wayne Grayson (English)

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• Accent Adaptation: To fit his alchemy theme, the dub gives him a German accent.
• Affably Evil: Even when he reveals his true colors as Amnael, he remains polite and personable.
• Alchemy Is Magic: Well, he never says so, but the way he uses it, it sure seems like it.
• The Atoner: After his defeat as Amnael, he provides an instrumental piece to defeat Kagemaru.
• Badass Bookworm: He can put up quite the fight with his alchemy-themed Deck while punctuating it with a lecture about alchemy.
• Badass Cape: Sports a billowing, hooded grey cape upon assuming the identity of Amnael. He then proceeds to thoroughly school several of the protagonists.
• Barred from the Afterlife: Humorously, it's because of his soul being swallowed by his cat that he lingers around as a spirit and doesn't pass on.
• Beware the Nice Ones: Certainly the nicest of all of the teachers at Duel Academy. Also one of the Seven Stars/Shadow Riders with probably the most powerful deck and greatest skill out of them all, as well as his fellow teachers.
• Blood from the Mouth: Happens in a flashback explaining how he contracted a fatal illness.
• The Bus Came Back: He returns as Amnael, defeats Chazz and Alexis, takes their keys and nearly defeats Jaden.
• The Chew Toy: Literally! After becoming a Spirit Advisor, he's often swallowed by his cat Pharaoh.
• Cool Teacher: In the first opening, "Kaisei Josho Hallelujah", you can see him on a motorcycle. In episode 13, he sicces his cat Pharaoh on some evil scientists.
• Crippling Overspecialization: Aside from the fact that his Alchemy Beasts are capable of attacking his opponent directly, at its core, Amnael's Deck revolves around banishing his own monsters to beef up the ATK of his Golden Homunculus and Helios cards. Once Jaden manages to summon Elemental HERO Electrum, his entire playing style is rendered useless as his cards that were banished are returned to his Deck, allowing Jaden to finish him off with one hit.
• Crouching Moron, Hidden Badass: His airheadedness is probably genuine. Regardless, he's the strongest of the 7 Shadow Riders and is able to defeat half of the main cast.
• Double Agent: He took the job at Duel Academy in order to gain access to the Spirit Keys.
• Double Reverse Quadruple Agent: He's a Shadow Rider who's undercover as a professor at the Academy, but in the end his goals are still nobler than some of the others and he actually wants to stop the Sacred Beasts from being released by nurturing a strong Duelist capable of taking them on.
• The Dragon: As Amnael. He is the strongest Seven Stars Assassin/Shadow Rider, but he's still second to Kagemaru.
• Easily Forgiven: No one seems to hold the fact that he is Amnael against him after he is defeated. Then again, he is just a disembodied spirit afterward.
• Evil All Along: Played with. While Banner is revealed to have always been a Shadow Rider, his intentions were to find a Duelist who can defeat them and keep the Sacred Beasts sealed away.
• Evil Mentor: Subverted in that while he's both antagonistic and a mentor, he doesn't actually try to turn Jaden evil, nor are his true intentions actually evil.
• Evil Sounds Deep: While masked, Amnael's voice in the dub is much deeper than Banner's usual voice.
• Eyes Always Shut: He only opens them when he Duels Jaden as Amnael.
• Gentleman Snarker: Everyone in the dub is pretty snarky, but only Banner can remain ever so polite while bringing the sass.
  Crowler: (After Jaden and Syrus beat the Paradox Brothers) This can't be! How'd they win? It's not fair...
  Banner: How? Because of your superb teaching, of course. Oh wait, they're in my dorm.
• Graceful Loser: As Jaden prepares to finish him off with Electrum, all he does is smile proudly knowing that his teachings haven't gone to waste.
• I Am Not Left-Handed: Usually a total goofball, but his Alchemy Deck is pretty strong. He defeats Chazz, Alexis, and nearly Jaden.
• Killed Off for Real: Both his original and clone bodies turn into dust, however, his spirit sticks around, mostly because Pharaoh refuses to let him move on to the afterlife and keeps him in his stomach.
• Kindhearted Cat Lover: He has a cat, he says "nya" at the end of his sentences, and is one of the nicest faculty members on the campus.
• Large and in Charge: The head of the Slifer Red dorm, and strongest of the Shadow Riders, who stands at a towering 200 cm^note 6 ft 6 in tall.
• Mechanically Unusual Fighter: For the time period, Amnael's Alchemy Deck is treated as such. Rather than relying on Normal Summons or an immediate Fusion Summon for his opening play and then building on from there, all of his monsters are Nomis (meaning they cannot be Normal Summoned) and all rely on being directly banished rather than going to the graveyard. The end result is that he is able to swarm the field with monsters much faster than his contemporaries, and due to the self-banishing strategy, is able to either draw a lot more cards to maintain his hand advantage, or power-up his ace monsters to very high levels.
• Mentor Occupational Hazard: Interestingly, he becomes more of a mentor after his death.
• Nice Guy: Quite possibly the nicest teacher in the Academy (Emi is the only one who can contest him), which almost makes up for the Slifers getting treated like crap by everyone else. It goes away somewhat when he turns up as Amnael, but comes right back when the mask comes off, indicating that he was never pretending to be nice and really is just that friendly.
• No-Sell: His Elemental Absorber trap card renders him immune to any of his opponents' monster attack by banishing a monster card from his hand with the corresponding attribute.
• Obfuscating Stupidity: He plays the part of the scatterbrained professor as a part of his cover. Though it might not all be an act.
• Our Homunculi Are Different: He caught a fatal illness and created a new body to put his soul into, leaving the original to mummify. His current body is slowly falling apart, which he's hoping to remedy with the power of the Sacred Beasts. After losing to Jaden and entrusting him with the means to fight Kagemaru, both the homunculus and his original body turn to dust.
• Put on a Bus: He suddenly disappears during the SSA arc. For good reason.
• Red Eyes, Take Warning: He opens his eyes when Dueling against Jaden in his Amnael persona, revealing them to be an unsettling red befitting the penultimate villain of his arc.
• Right-Hand Cat: His cat Pharaoh.
• Secretly Dying: Throughout the entire first season due to his homunculus body beginning to decay.
• Spared by the Adaptation: Played with. While 4Kids did not edit out his "death", in the original version, Kabayama/Sartyr is aware that Daitokuji/Banner passed away. In the dub, Kabayama/Sartyr is still under the impression that he's missing.
• Spirit Advisor: To Jaden, against Kagemaru and a few times afterward. He takes up this role permanently in the final episode, deciding that following Jaden around would be more exciting than continuing to stay at Duel Academy.
• Treacherous Advisor: Moreso in the dub, where he claims to have rigged all of Jaden's previous Duels to make him think he was a good Duelist (once beaten, he admits he lied about that as a test of character for Jaden). Ultimately downplayed as while he is the penultimate boss for the arc, his end goal was to stop the release of the Sacred Beasts all along and genuinely does try to mentor Jaden; in the original, he merely continues lecturing about alchemy even as he and Judai face off, believing that Judai has the potential to learn from it, even encouraging him as a sort of Stealth Mentor in the final turn of their duel.
• Verbal Tic: Japanese version only - while Daitokuji-sensei often says "nya" (Japanese for a cat's meow) at the end of his sentences, other languages eliminate it altogether, and give him a German accent because he teaches alchemy.
• Weak, but Skilled: His monsters either have a measly 500 ATK or depend on having a large number of banished cards to be strong but he's still a threat thanks to the 500 ATK ones being direct attackers and having more than enough methods to banish cards easily.
• White Hair, Black Heart: As Amnael he's a ruthless duelist who crushes his opponents mercilessly. That said, he did allow Jaden and the others a chance for survival, so this is at least somewhat played with.
• Why Did It Have to Be Snakes?: Has a fear of vampires above all else; when it's revealed that one of the Shadow Riders is one, he freaks out and pulls every vampire-repelling trick in the book.

Principal Samejima (Chancellor Sheppard)

Samejima (鮫島) (Sheppard)

Duel Academy's principal and former master of the "Cyber Style", which Zane inherited.

He uses a Cyber deck, with Cyber Ogre 2 as his trump card.

Voiced by: Masami Iwasaki (Japanese) and David Wills (Engish)

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• Adults Are Useless... and depressed by his awareness of that. Despite his position, he fails to accomplish any form of proper authorial displays and was either too passive or just plain powerless to protect his students from the various supernatural forces at work.
• Bald of Authority: He is the leader of Duel Academy and has a very shiny dome, though he rarely actually takes meaningful action in spite of his authority.
• Be Careful What You Wish For: He hoped that inviting Professor Cobra would motivate Judai into becoming a more matured duelist and accelerate his growth. Well, technically Cobra succeeded, as Judai by the end of Season 3 accepted his role as the Supreme King, wielder of the Gentle Darkness, and emerged in Season 4 at the zenith of his spiritual power...all at the cost of his happiness and having to grow up in the most traumatizing way possible, a funk that he truly wouldn't be able to snap out of or learn from until Yugi stepped in at the end of the series.
• Fatal Flaw: It doesn't kill him, but it harms his students, and that is passivity. Sheppard quite frankly is not an active participant in the series, and that has terrible consequences to Duel Academy's alumni.
• Horrible Judge of Character:
  • After Ryo/Zane's makeover into Hell Kaiser Ryo, Sheppard understandably believes that his former pupil has undergone a Face–Heel Turn and tried to bring him back into the light. However, as shown in Atticus' duel against Hell Kaiser Ryo, it's shown that Zane never actually turned evil despite his new obsession with victory and the use of Underground Dueling.
  • For Judai's third year, he thought it was a good idea to hire the Obviously Evil Professor Cobra/Viper, which puts his students in serious danger no thanks to the Survival Duels. He continues to trust the guy even as it becomes clear that everyone else does not.
• Nice Job Breaking It, Hero: He has a pretty serial case of this, to the point where most of the problems in the series can be traced to him.
  • In the first season, he failed to tell anyone about Kagemaru despite knowing who he was, and handed the Keys to prominent students instead of just tossing them off a bridge.
  • He left for most of the second season to let Crowler and Bonaparte run the school and allowed the Society of Light to take root, and when he came back, he started the GeneX Tournament, which failed to attract the person it was meant to attract or redeem the person it was meant to redeem, and decided to comply with Sartorius' request to invite Ojin, indirectly handing the laser satellite to him.
  • Season 3 would have gone a lot differently if he hadn't brought Professor Cobra to Duel Academy, making his scheme possible. To make matters worse he leaves again just as all of the students are passing out due to the Dis Bands.
• Old Master: Of the Cyber Style of dueling, of which Kaiser/Zane is also a practitioner. Kaiser has long since surpassed him in this regard, of which he is painfully aware.
• Reasonable Authority Figure: Presented as this when it comes to allowing Jaden to enroll and protecting him from Crowler's schemes... but not so later on in the later story arcs. He played right into Kagemaru's hands concerning the duels for the Spirit Keys in the second half of Season 1, and while the students are overjoyed in Season 2 when he returns from his sabbatical to replace the head-butting Crowler and Bonaparte, he ultimately allows the White Dorm to stay and thus enabled Sartorius to continue with his plans. This gets at its worst in Season 3; it's Crowler and Bonaparte who are the reasonable ones who want to shut down Professor Cobra's dis-duels, but Sheppard allows them to go on and leaves on a trip at the most critical point.

Emi Ayukawa (Fonda Fontaine)

Emi Ayukawa (鮎川恵美) (Fonda Fontaine)

Duel Academy's nurse, gym teacher, and the head of the Obelisk Blue girls' dorm.

She uses an Anti-Cure Deck, which turns life gain for her opponent into effect damage.

Voiced by: Michiko Neya (Japanese) and Veronica Taylor (English)

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• Alliterative Name: Two "F" names in the dub.
• And Then John Was a Zombie: Is turned into a Duel Ghoul during Season 3, due to putting herself in harm's way to protect an injured Blair.
• Ascended Extra: She becomes much more prominent in the first half of Season 3, due to Viper's survival duels, and later the Duel Ghouls, meaning that the students require constant medical attention. She is notably the first staff member to turn on Viper and suspect he is not to be trusted.
• Deadly Doctor: She's the school nurse, but plays an anti-cure deck that reverses LP gain into LP loss.
• Harmful Healing: Her anti-cure deck uses Nurse Reficule the Fallen One, who can undo and reverse LP gain effects.
• Hot for Student: For Atticus. She is seen alongside most of the female students in Atticus' rabid fangirl cheering section. The first Tag Force game expands on this, as she will only agree to be the player's partner if they bring her Atticus' autograph.

Napoleon Kanou (Jean-Louis Bonaparte)

Napoleon (ナポレオン) (Jean-Louis Bonaparte)

Cronos' replacement during the former's reign as Duel Academy headmaster and Marcel's dad.

He uses an (anime-only) Toy Soldier deck, whose theme is the conquests of Napoleon.

Voiced by: Naoki Tatsuta (Japanese) and Mike Pollock (English)

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• And Then John Was a Zombie: Temporarily turned into a Duel Ghoul in Season 3 when Duel Academy was sent to the different dimension by Yubel.
• Big Bad Wannabe: Tries to destroy the Slifer Red dorm during the first half of Season 2, much to Dr. Crowler's disgust, viewing it as a stain on Duel Academy's prestige...but as he was hired by Crowler, who was already a Harmless Villain by that point, his impact is lessened. His schemes on that front do not go very far; the Society of Light quickly become the main threat, and while he does collaborate with them a few times early in their establishment, it ultimately goes nowhere by the time of the Genex Tournament.
• Death of a Thousand Cuts: He specializes in inflicting meager degrees of battle and effect damage in enormous quantities.
• The Cameo: His final appearance on episode 157 amounts to this as he's Put on a Bus.
• Fangs Are Evil: He has quite prominent canines, and early on was portrayed as a meaner Crowler.
• Fat Bastard: He starts out as a short, chubby version of pre-Character Development Crowler.
• French Jerk: Though he does eventually lose some of the jerk.
• Gonk: Not much better than Crowler in this department. He's a short, stocky man with a puffy face that looks more than a bit like a bulldog.
• Gratuitous French: He seems to like to dip some of his sentences in it.
• Hate Sink: In Season 2. With his dickishness towards the Slifers, he pretty much takes over the spot of "punchable antagonistic character" after Crowler Took a Level in Kindness.
• Heel–Face Turn: Season 3 forces him to come to terms with how much of a jerk he is thanks to witnessing his fragile son at the mercy of Viper and Yubel. He ends up better for it.
• Hidden Depths: Season 3 has him actually care about the students, mostly brought on by the presence of his son Marcel.
• Huge Girl, Tiny Guy: While only seen in shadow, his ex-wife was clearly at least two heads taller than he was.
• Jerkass: To put his jerkishness in perspective, even Crowler at his worst never tried to demolish the Red dorm.
• Jerk with a Heart of Gold: Far less than Chronos, since he's far more of an elitist, but he does genuinely care about the students of the school enough to put himself in danger to save them.
• Keep It Foreign: He's called Wellington, and is English, in the French dub.
• Magikarp Power: His Toy Soldier monsters have poor stats, but his deck is loaded with spells and traps to power them up and protect them from his opponents' monsters.
• Meaningful Name: His name, deck, and nationality are clear references to Napoléon Bonaparte.
• The Napoleon: Right down to the name. He's so short that his Duel Disk has a wheel so it won't drag across the ground while he's carrying it.
• Papa Wolf: But not as much as he'd like. He purposely isolates himself from Marcel because showing favoritism towards a student is taboo for a teacher. (And it's the hardest thing he ever had to do, as he admits.)
• Put on a Bus: Left to spend time with his son Marcel, so he was absent in season 4.
• Replacement Flat Character: He's practically Pre-Character Development Crowler in Season 2, while the latter continues to Took a Level in Kindness.
• Sadist Teacher: He loves to torment students that don't live up to his expectations. In the original version, this is revealed to be mixed with Stern Teacher in Season 3, but it bites him in the ass since we see how this bleeds into his home-life. He is divorced from his wife to his dedications to his teaching philosophy, and his son has been left with crippling self-esteem issues.
• The Starscream: He tried to undermine Crowler and get Slifer Red torn down and turned on him at first when a job opportunity was available with Pegasus.
• Too Dumb to Live: During his duel with Crowler, he claims that he adjusted his deck and strategies to perfectly counter Ancient Gear cards, but stupidly included Negate Attack, a trap that's completely useless against most of that archetype's heavy hitters.
• Took a Level in Kindness: In season 3.
• Trap Master: His deck includes a number of Trap Cards to interrupt his opponent's plays and attacks, and his ace monster Toy Emperor can add a Trap from his deck to his hand upon destroying a monster.
• Verbal Tic: "De aru" in the original version. He and Crowler once got into an argument ridiculing each others' tics.

Professor Kouji Satou (Mr. Stein)

Kouji Satou (佐藤浩二, Satō Kōji」) (Mr. Stein)

One of the less important teachers at duelist academy, teaching duel theory, and history. He appears in Season 3 as an associate of Viper's to stop Jaden.

He uses a Scab-Scar Knight deck based around taking control of his opponent's monsters.

Voice actor: Mitsuru Miyamoto (Japanese) and Marc Thompson (English)

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• Adaptational Jerkass: In the dub, his beef with Jaden is a petty grudge and he blames Jaden for things that are his own fault, i.e. stretching himself too thin and ruining his own professional career and being a dull, uninteresting teacher. In the original, he's still misdirecting his anger, but his reason for being so spiteful is slightly less self-centered.
• Affably Evil: He never once stops being polite, even as he blames Jaden for ruining everything.
• Badass Teacher: A former pro player and he would have outright defeated Jaden (albeit, he was hampered by self-doubt) if he had just attacked instead of attempting a Taking You with Me.
• Berserk Button: Being ignorant in any way is one for him, to the point wherein the analogy of two people encountering a piece of trash on the floor (the first person noticed it, but didn't pick it up whereas the second one didn't pick it up since he didn't see it), he believes that the second one is the worst compared to the first one.
• Broken Pedestal: He idolized Alexis as the ideal student, but eventually found out that even she stopped attending his class and thus had no issue with her being drowned by Viper.
• Career-Ending Injury: He was forced to retire from Pro Dueling after falling very ill from upholding his financial responsibilities to his family and attending night classes to earn his teaching degree.
• Corrupted Character Copy: In the original version, he can be seen as one to Frank Grimes. Like Grimes, Satou was constantly beaten down in life, in his case dueling ten times as much as the average pro to support his family, only to collapse at his most critical moment, and when trying to become a teacher, went over the Despair Event Horizon thanks to Judai's laziness becoming a negative impact on the students, not unlike how Grimes went insane dealing with Homer Simpson, another Idiot Hero. But whereas Grimes limited his grudge to Homer and was a Cosmic Plaything, Satou is fully on board with Professor Cobra's plan to essentially kill Duel Academia's students via the Dis-Belts; upon learning that even Asuka abandoned his classes, he had no problem with her being drowned. Satou is thus tragic, but an enemy that has to be defeated nonetheless. While Grimes never succeeded in impacting his personal enemy, Satou did, becoming the first villain to actually get Judai to seriously question himself, leading to his own breakdown later down the line.
• Creepy Monotone: At first it's almost comical, as befitting an expy of Ben Stein. But as the duel goes on and he reveals more of his motivations and personality, his incessant droning becomes far more sinister.
• Demoted to Extra: In the dub, Professor Viper takes most of Professor Stein's impact; in the original version where Jim is peering into Judai's soul via the Eye of Orichalcum, Satou appears to mock Judai for his weak convictions along with Cobra, but this was cut from the dub.
• Detrimental Determination: In his backstory. He pushes his physical and mental limits to the max when making his family's financial situation better as a Pro Duelist along with juggling his academic studies for a teaching degree. Unsurprisingly, his body collapsed from the stress and he became so ill to the point of having to retire from Pro Dueling altogether.
• Disney Villain Death: Falls to his death after being defeated by Jaden.
• Disproportionate Retribution: For the crime of "slacking off", he decides to let his students die, even personally trying to finish off Jaden.
• Even Evil Has Standards: He is briefly opposed to continuing the duel while Alexis is drowning. This is subverted when Viper shows him footage of Alexis skipping Stein's lesson, and Stein quickly changes his mind.
• Expy: Of Ben Stein in the dub. The original version makes him out as a bit of a Corrupted Character Copy of Frank Grimes.
• Fallen Hero: He became a pro player to protect his family, always bearing the burden of responsibility until it broke him. Represented by his ace card being a knight covered in scabs and scars.
• Green-Eyed Monster; It's clear that he envies Jaden for his skills as a duelist and natural charisma. This only added fuel to his fire for "revenge", as well as causes him to incorrectly assume that Jaden looks down on him.
• Jaded Washout: A rather more tragic example. The burden of his family obligations alongside his pro career caused him to literally collapse, so he had to turn to teaching instead. Then he ends up teaching a bunch of lazy students who barely listen to his lectures, which is such a depressing experience that it drives him insane. In the dub, this is changed to him being unable to handle studying for his teaching degree and a pro-dueling career at the same time, and being so boring that he barely notices that he's teaching an empty classroom.
• Ignorance Is Bliss: Defied and deconstructed. Satou hates ignorance of any form, and considers those who are genuinely ignorant of something to be Eviler than Thou than those who are willfully ignorant (i.e. those who are aware of something but choose to look the other way).
• Insane Troll Logic: His claims that those who ignore litter on the ground are worse than those who don't notice it since the former "can one day pick it up". By that reasoning, the ones who don't realize said litter could also one day recognize their mistake.
• It's All About Me: Despite stating to be upset at Jaden for causing the students to not reach their full potential, it's obvious that he's mostly just bitter about his own misfortunes and is (at least partially) using Jaden as a scapegoat.
• Killed Off for Real: Which, quite frankly, is unusual for this series; he has all of his duel energy drained by the Bio Bands and falls to his death.
• Knight of Cerebus: The duel against him sets the tone for the rest of the season and he's the first human character to specifically die. Only the sub carries this dark tone from him as Professor Viper takes most of Professor Stein's role in the dub.
• Moral Myopia: He became upset at Jaden for "leading the others astray", yet has no qualms endangering his own students' lives.
• Nap-Inducing Speak: His voice seems to have been intentionally made to sound as boring as humanly possible. Jaden falling asleep in class isn't surprising, but there's something to be said about him putting everyone else to sleep as well. For the record, even BASTION MISAWA is shown having fallen asleep and eventually stopped attending.
• Never My Fault: While it's true that Jaden and the others should have been more respectful towards Stien, his dull teaching style and lack of disciplinary action really didn't help the issue at all. In fact, had Stien simply been more upfront with his feelings to begin with, the students would have likely changed on their own terms.
• No Celebrities Were Harmed: His name and soporific voice in the dub are a direct reference to Ben Stein, particularly his role as the Economics Teacher in Ferris Bueller's Day Off.
• Not Helping Your Case: His arguments about students needing to be more serious with their class work would mostly be in the right, were it not for the case that he became a deranged lunatic that's helping Viper's plans.
• Remember the New Guy?: Stein's existence has never even been alluded to prior to his debut, but Jaden has apparently been in his class before.
• Scars Are Forever: In a mental and figurative sense, his Scab Scarknight is a representation of being broken down by the responsibility he upholds prior to becoming a teacher at Duel Academia.
• Shadow Archetype: Stien is essentially Zane if the latter had broken down instead of snapped.
• Shout-Out:
  • The design of his Scab Scarknight resembles Evangelion Unit-01, which is not only fitting for the numerous references of the mecha anime in the later seasons of GX, Stein's character and death also set the series in a much darker tone.
  • In the Japanese version, he quotes the iconic catchphrase from Spider-Man.
• Small Role, Big Impact: He appears only in two episodes and once in a flashback yet the duel against him is what made Jaden begin to question his carefree attitude, starting the downward spiral that led him to cross the Despair Event Horizon. Subverted in the dub where his impact is heavily reduced.
• Stern Teacher: Deconstructed; the reason he is such a Stern Teacher is due to the tragedies in life that he experienced, which bled into his learning style. Unfortunately, because of these tragedies (and some convincing from Viper), he takes his job of molding young minds so seriously that he comes to regard any form of ignorance as deserving of death, planning on doing so to Judai, hoping that Viper's goals kill all of the students, and having no problem with Asuka drowning once learning that she also skipped his classes.
• Taking You with Me: Attempts to do this to Jaden at the end of their duel.
• "The Reason You Suck" Speech: Delivers an elaborate one to Jaden regarding his carefree attitude and his lack of consideration for the less gifted students who emulate him and the negative impact it has on their studies.
• Tranquil Fury: Despite his entire motivation being frustration and anger, he remains unshakably polite. Especially visible during his introductory scene as he announces his intention to take revenge on his students while talking as if he's giving a history lesson.
• Villain Has a Point: A villain he might be, but he is right about Jaden having a negative impact on other students. Due to his apathy towards actual schoolwork and talent in dueling, other students have stopped going to Stien's class from believing that they don't need to work hard to become great duelists themselves. It is downplayed given that Jaden is commonly held in contempt despite his feats so it's not that surprising that he doesn't realize he's seen as a role model. Plus, it's not as if Jaden has any real obligation to motivate his classmates, since their gradework is their own responsibility.
• Villain of the Week: Essentially. He shows up for one duel against Jaden, then gets killed off.
• With Great Power Comes Great Responsibility: A rather tragic deconstructed example. He firmly believes in the idea of upholding the responsibility of financially supporting his poverty-stricken family by becoming a Pro Duelist, and at the same time, studying intensively for his teaching degree at night. The overall workload and pressure he faced under those conditions have led him to become so ill that he collapses during an important duel against The D, forcing him to retire from Pro Dueling altogether and having to teach a whole class of lazy students are where he went off the deep end.
• Would Hurt a Child: Not only is he responsible for forcing all of the Duel Academy's students to participate in the survival games by helping Viper, but there's also his grudge against Jaden specifically.

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