* AccidentalInnuendo: In the original, Edo (having the D-Hero deck), often says things like "the power of the D" or similar in reference to destiny. When "the D" is taken to be the OTHER one, some really hilarious accidents occur.
* AmericansHateTingle:
** Yubel gets shunted off to the side a lot in the English-speaking fandom, but she (and her relationship with Juudai) appear fairly popular in Japanese fanart.
** The GX anime in general was a lot better received in Japan than in English-speaking fandom.
* AntiClimaxBoss: [[spoiler:Despite having a very powerful deck, Darkness has a rather poor showing against Judai in his final duel with him.]]
* AwesomeMusic: The dub's guitar soundtrack.
* AssPull: It's amazing what you can do when the main character's deck is based entirely around fusion. Plus all the E-Hero support cards that are just completely useless in real life due to how specific they are. Ryo's initial Deck focused on a single monster and its Fusions, and getting the same results in a real-life Deck would take incredible luck.
* BadassDecay: Manjoume in Season 3.
** Misawa in the second season.
* BaseBreaker: Johan. The fans seem to be divided on whether he's the [[EnsembleDarkhorse best character in the entire show]] who deserves his own spin-off or a bland, spotlight-stealing MartyStu, with not much middle ground.
* BigLippedAlligatorMoment: In episode 20, while Judai, Sho, and Hayato are scrubbing each other's backs, [[https://24.media.tumblr.com/05f0eec3d86e2f5d6b150e6b07dc92fa/tumblr_n49j43vtkE1s9gsu0o4_500.png Judai would then realize that he's scrubbing a bear's back]] while the bear scrubs a seal. That hilarious incident was never mentioned since, and it was also cut from the dub due to partial nudity.
* BrokenBase: Yubel being PutOnABus in Season 4, people say good riddance to her, others want to explore her and Jaden's relationship with each other more.
** Jaden's new personality in Season 4 received mixed reactions from fans.
** Season 4 not being dubbed ''at all'' is still a sore topic for the English-speaking fans of the show.
* CompleteMonster: [[Monster/YuGiOh Has its own page]]
* DieForOurShip: Asuka is subjected to this from some shippers who pair Judai, her canonical crush, with anyone other than her (aforementioned "some shippers" are often {{Yaoi Fangirl}}s).
* DracoInLeatherPants: Hell Kaiser, and to an extent, Edo Phoenix.
* EvilIsSexy:
** Hell Kaiser Ryo, Possessed Johan, Darkness Fubuki. The Supreme King.
** The ladies have less to offer, but there's still Yubel and the Seven Star Camula.
* EpilepticTrees: Since quite a lot of things were hinted at but never filled in, this should come as no surprise.
* FauxSymbolism: All three Sacred Beasts are named after Judeo-Christian angels.
* FriendlyFandoms: ''5Ds'' and ''GX'' fans typically like each other a lot more then they would like ''Zexal'' and the original series fans, largely due to how they had entire seasons not dubbed by 4Kids.
* FunnyAneurysmMoment: Remember the fun Juudai and the gang had about Sho's card crush on [[DarkMagicalGirl Dark Magician Girl]]? Flip it around, add in StalkerWithACrush tendencies, and throw in a pinch of NightmareFuel, and you have the premise for Season 3.
* GeniusBonus:
** For those attentive enough, the series is full of references to alchemy and tarot, including a {{Foreshadowing}} to the antagonist of the final season.
** The duel in Episodes 153-155 appears to have been structured to mirror or strongly resemble a Jewish wedding, beginning with Magic Chronicle as Yubel's dowry and the ketubah (Jewish wedding contract) and ending with a "cracked glass" when Juudai manages to take back Super Fusion and [[spoiler: join his soul to Yubel's]], something he reveals only after the worlds start shaking apart and the window in Samejima's office cracks and shatters. With the exception of a couple of Juudai's more convoluted turns, it's actually possible to trace every single turn back to the ceremony, in perfect sequence. The resemblance even continues after the duel--in a Jewish ceremony, the ceremony is complete when the bride and groom retire together, away from the guests (represented in this case by Sho and Ojama Yellow). The German dub even adds a touch of its own, with Syrus commenting that "[Jaden] and Yubel are united among the stars".
* HilariousInHindsight: The [[TakehitoKoyasu voice actor]] for Takuma Saiou, the one who played Arcana Force XXI - The World in the GX cartoon, ended up voicing Dio Brando in the 2012 cartoon adaptation of ''Manga/JoJosBizarreAdventure''.
* HoYay: A moderately-sized plot point for season 3 is that Yubel (who is a hermaphrodite using male pronouns for "her"self; Juudai also refers to her as "he") believes that Juudai (who is male) loves/is infatuated with/spends too much time with Johan (also male). It's unclear if this is lampshading, or just YGO being YGO.
** A special mention has to go to a piece of HoYay so blatant it borders on hilarious: while Yubel is utilizing Johan's body, she calls Juudai her beloved, tells him she will "show [him] the truth of [her] undying love," and tells him "aishiteru, boku no Juudai" ("I love you, my Juudai"). Seeing screencaps with subtitles taken out of context may be enough to drive some Juudai/Johan fangirls straight into hysterics.
*** Episode 147 features "Johan" calling Juudai "my beloved" (or, depending on your subs, "in just a moment I'll show you the truth of my love"). While everyone around them gasps, Juudai just kind of stands there with no reaction whatsoever. One Japanese-to-Spanish fansubber takes the nuance even further: because of the different words for "love" in Spanish, the line translates from Japanese to Spanish to English as "In a few seconds I'll show you the truth of my desire, Juudai, my love." Given the context, there really is only one way to interpret that.
* InformedWrongness: A Season 1 episode features the one-shot character Mitsuo/Pierre, a gambler who uses cards that rely on coin tosses to trigger their effects, and uses Second Coin Toss to redo the toss if he fails to get the needed result. Asuka declares that the only reason he's winning the duel with her is that he relies on Second Coin Toss to win his coin throws and without it he would have lost them all, and proceeds to destroy it and then attack for the win when he gets his last toss wrong. We're supposed to see Mitsuo as a cheater and a coward, but his strategy is perfectly valid and worked very well. The only reason he lost is that he didn't use his monster's effect to try and inflict 1000 damage to Asuka, if he had done so and got it right, he would have just won in two turns.
* JerkassWoobie: Cobra. All he wanted was to reunite with his dead adopted son, and he would no longer have any reason to be an antagonist if he met his goal. Amon wanted to create an idealistic world, and though [[UtopiaJustifiesTheMeans he kills two people in the process]] ([[spoiler:Echo and Ed]]), the former willingly sacrificed herself and the latter started a duel to protect the former, knowing the consequences of losing. Both are [[NeverFoundtheBody presumably]] killed by the far less sympathetic Yubel.
** Camula may count, She's the [[LastOfHisKind Last]] of a race of Vampires that were wiped out hundreds of years ago by humans who attacked them unprovoked and she sealed herself in a coffin to survive and waited for eons to be freed. She seeks to restore her Race but she sacrifices The Souls of those she defeats in Duels to do so.
* LadyMondegreen: Oh 4Kids...their dub of episode 154 will forever haunt them. The filter voice they put on Yubel distorted her voice so oddly that, at one point, she ended up sounding like she dropped an [[http://www.youtube.com/watch?v=n4sDFMPmLWY F-bomb]] when she says ''fight''.
* LauncherOfAThousandShips: Judai. Also Asuka, being the only major, non-jailbait female protagonist.
** This is the guy who doesn't know [[ObliviousToLove what a fiancée is]], let alone know [[ChasteHero how to have sex]]. Ironically, Judai/Asuka lemons tend to be [[PornWithoutPlot exceptionally graphic]].
* MemeticMutation: From the manga, Johan's '[[DissonantSerenity It]] [[BlatantLies was]] [[NightmareFuel a happy duel]]'.
* MemeticSexGod: Jaden. He is [[LauncherOfAThousandShips shipped with everyone]], and is generally portrayed as good at sex. Also has a lot of harem fanfiction written about him.
* MisaimedFandom:
** People mainly fail to realize that the show is an AffectionateParody of the original series, especially in the early seasons, and later heads into DeconstructorFleet.
** Asuka/Alexis was a {{Deconstruction}} of MsFanservice, she was annoyed by how people saw her as an attractive girl and wanted to be seen as a person and a duelist instead of just a pretty face. Many fans don't care since this gets in the way of {{Shipping}}, and other fans often use it just to bash her for being a "slut."
* {{Moe}}: Rei, and her Maiden in Love monster from her first appearance.
* MoralEventHorizon:
** Zane Truesdale (Ryo Marufuji) in the second season crosses the line after donning his Dark Kaiser persona when he electrocutes and almost kills his little brother Syrus (Shou) in a duel, never giving a damn about doing that, only about winning.
** Amon when he sacrifices Echo and apparently kills Aster to obtain Exodia.
** Yubel at every attempt in the 3rd Season with Jaden.
* NightmareFuel:
** Yubel, period. Even creepier when the dub gave it the voice of a spoiled 5-year-old girl.
** Brron, who is...some kind of semi-human-only-not-really skeleton...thing.
** Titan's [[FateWorseThanDeath fate]] when he abuses the power of Shadow Games.
** Darkness, with his MindRape and GrimReaper-eque form.
** The Underground is less supernatural, but still incredibly disturbing.
* OneSceneWonder: For the dub. He may only have two episodes and is a minor character, but Marc Thompson's voice acting, the usage of the original series themes and cards, and the genuinely good duel he gave Jaden, make Dimitri far more memorable than a lot of other characters with larger roles.
* SuperlativeDub: Episode 18 and 19 with Dimitri, the copycat duelist. In the original Dimitri was just Dimitri and only decided he ''was'' Yugi towards the end of the duel, but in the dub Dimitri acts like he's Yugi all along. What ''really'' sells the episode though is the absolutely [[NarmCharm Narmtastic]] impersonation of Dan Green's Yami Yugi that Marc Thompson delivers, taking Green's LargeHam, cranking it up, and giving a few lighthearted jabs at his mannerisms and catchphrases. The dub also re-uses parts of the original dub soundtrack as further nostalgia fuel when Dimitri makes his moves.
* TastesLikeDiabetes: Episode 20 with that Maiden in Love deck is absolutely sickening.
* TearJerker:
** Season 3, more so as it continues. Ryo's death may be the top.
** From Season 4, Episode 178: Yubel being forced [[spoiler: to attack Juudai head-on by Darkness]]. The look on her face as she's forcibly dragged across the arena an inch at a time is absolutely heartbreaking. Followed by a CrowningMomentOfHeartwarming when Juudai [[spoiler: takes her hand and vows "I'll get you back, no matter what!"]]
** Fubuki [[spoiler: screaming for Asuka after she's lost to Darkness]].
** From the manga, when Midori [[spoiler:realizes she has to sacrifice the possibility of getting information on her younger brother Koyo's coma out of Reggie to prevent Judai from having to duel her, accompanied by a mental vision of Koyo telling her she's doing the right thing. She's unable to win, though, and collapses, comatose in front of Judai]].
* TheyWastedAPerfectlyGoodPlot:
** Johan is a ChosenOne, but of what? [[FridgeBrilliance Possibly of the Crystal Beasts...]]
** What was Yubel during the twenty episode absence after possessing Johan but before confronting Juudai?
** Rogue card designer with a counterfeit Egyptian God? The whole thing resolves in ''one episode''.
** What were [[spoiler: Judai and Yubel off doing after they fused?]] It's implied that Judai was gone for quite a while (enough for most people to think that he was gone for good), so what were they doing?
*** It's implied that they were going to [[spoiler:go and kick the Light of Destruction's ectoplasmic patuckus]], making this closer to OffscreenMomentOfAwesome given that it wasn't actually shown (probably because it didn't involve card games).
** While the concept wasn't really wasted, the history of the Sacred Beasts/Phantom Demons is not explored at all, such as how evil versions of the God Cards were created and how they got sealed under the island.
** It's mostly based on the video games but a lot of people would prefer if Rei used Lightsworns instead of her current deck considering how much better the deck is.
* WhatAnIdiot: Why didn't anyone just remove/break their bio-bands during the ''Dimension World'' arc?
** Because they can't. It's mentioned at one point that they've tried and the only way they could would be to cut off their arms.
* {{Woolseyism}}: Yes, the dub did manage a few.
** The "Bio Bands" and "Survival Duels" in the dub were known as ''"Death Belts"'' and ''"Disclosure (seems benign, until you realize it's a pun on the Japanese pronunciation of death) Duels''". (called Dis-Duels in ''Tag Force 2''). God knows why the faculty weren't tipped off to the true nature of Cobra's actions when he pitched the idea in that version.
** That's easy. Because the Disclosure Duels had already been held in West School where Cobra worked before and nothing had gone wrong there. O'Brien even mentions that the effects are different.
** Banner's German accent.
** While the symbolism of the name is lost, it could be argued that Nightshroud is a more impressive name for a villain than simply "Darkness".
** The D, in the Japanese named "DD" for "Destiny Duelist". The dub established "The D" was an alias and gave him the proper name "Kyle Jables", take from Kyle Gass and Jack Black of ''Music/TenaciousD''.
** A bit of a mean one that nonetheless works -- the monkey duelist being trained by Kaiba Corp in Season 1 was named "Sal" in the Japanese version, meaning [[FunWithAcronyms "Super Animal Learning"]]. The dub renamed it "Wheeler", after one of Kaiba's favorite insults for Joey, "dueling monkey".