Code Lyoko is an Animesque show that was written and produced in France in English and French for simultaneous release in its home nation as well as the US — and about 160 other countries, including Japan (a rarity for a foreign animated show).It follows the adventures of a group of students at a Boarding School who discover a supercomputer in the basement of a nearby abandoned factory. The computer has modules that allow people from the real world to "virtualize" into the Cyberspace of Lyoko, where an evil A.I. named XANA is apparently hunting down a good A.I. named Aelita. The computer also has the ability to effect a temporal recursion (in Layman's Terms, rewind time) up to 24 hours in the real world.XANA manifests in Lyoko indirectly through a variety of monsters with various attacks and tactics, trying to capture Aelita and repulse her protectors from the real world. XANA also attacks the real world, which at first resembles the results of The Cracker, doing damage through various interfaces, but these attacks slowly gain a supernatural edge, including summoning monsters in the real world, and possession of students and teachers.The students often use the Return to the Past function to repair damage and effect a kind of Masquerade to protect Aelita, however with the knowledge that death is permanent -- not even time travel will bring them back.The five main characters (Aelita and her protectors) are occasionally referred to as "The Lyoko Warriors" or Team Lyoko. See the character sheet for individual descriptions.The recap pages of all the episodes is in construction.There is a short (5 minutes long) film made in 2001 by the creators of the show, Garage Kids, that is considered a test pilot for the series. It introduces the main characters and some future elements of Code Lyoko, though there are differences both visually and plot-wise. Code Lyoko began broadcast in France in 2003 on France 3 and Canal J, and in the United States in 2004 on Cartoon Network. The TV series ended in 2007 after four seasons and 97 episodes (including a two-parter prequel).As of summer 2011, a new twenty-six episode series was confirmed to be in production, titled Code Lyoko Evolution, and it was released in fall 2012. Evolution is a continuation of the original show, with live-action replacing the 2D segments. All tropes relating to this series should go on the Code Lyoko Evolution page.Between the two TV series, a novel series was produced by Atlantyca Entertainment. The series, originally written in Italian, takes place in a heavily expanded Alternate Continuity which promises to tie up some of the plot threads left hanging by the show. The series is officially available in 11 languages, not including English. The series includes the following books:
The Underground Castle: March 2009 (Italy), September 2010 (France)
The City with No Name: November 2009 (I), March 2011 (F)
The Return of the Phoenix: April 2010 (I)
The Army of Nothing: November 2010 (I)
Another project tentatively planned for the franchise is a MMORPG, which is still in the works despite a projected release in 2010 (and little to no news since). A Code Lyoko stage show was also produced and performed in Spain in March of 2011.
Code Lyoko provides examples of the following tropes:
Absurdly Spacious Sewer: Though it should be noted that his particular series is set in France, so it's not quite as unusual as usual. Also, the tunnel regularly used by the heroes is more of a storm drain than a sewer, since the water flows directly in the river.
Achilles' Heel: Megatanks are potentially the most powerful of all of XANA's monsters. However, because they're so big and bulky, they have trouble controlling their momentum, and this sometimes leads to them plunging straight into the Digital Sea. In fact, if you get enough running momentum going, you can literally push them to their doom. Consequently, they're the one kind of monster most frequently taking a dive in the show. Yet they are also seen repeatedly stopping instantly to aim at one of the heroes.
Adults Are Useless: On most of the occasions that adults did become aware of XANA's actions, they attempted to barricade the heroes for their own safety, often at times in single room at the school. On the odd occasion they actually did help the kids, the Reset Button abuse resulted in them forgetting everything after they found out just what the kids were really doing. In fact, adults were often XANA's targets when he decided to possess someone, and one of the side effects of Specter possession is total memory loss for its duration.
Alice Allusion: A rather odd example, but do you think Odd's Lyoko form is a "giant purple cat" just because? Do note the one episode where teleportation in-Lyoko causes cloning... Maybe Mr. Cheshire can do that.
All There in the Manual: A lot of the "game" mechanics in Lyoko are rarely if ever explained in the show itself (and are often contradictory there); we only know about them because of supplementary material. And even then, despite figures given about every combatant's weapons and Life Points, everything defaults to the Rule of Drama. Any shot fired will either misswildly, bring its target to a ridiculously low amount of Life Points, or inflict a one-hit kill. The monsters' laser beam can be stopped by the Lyoko Warriors' defenses, though. In addition, it's stated elsewhere that Aelita loses half her life points every time she uses her Creativity, despite the fact that in-universe there's no evidence to suggest this is true.
All Your Powers Combined: William's Super Smoke is Ulrich's Super Sprint combined with Aelita's flight with the added bonus of making him invulnerable. He can also deflect attacks (like Odd), use telekinesis (like Yumi), fire energy (like Aelita), and use at least one form of Aelita's Creativity (i.e. manipulating electronic locks). Finally, he can enter the Code: XANA in the towers.
Almost Kiss: "Routine". Real badly-timed Return to the Past, there.
Always Save the Girl: Particularly in Season 1, when Jérémie would rather risk XANA destroying the world than turning off the supercomputer and losing Aelita.
Ambiguous Gender: XANA. Though it makes sense that XANA is an A.I. and thus neither male nor female. Still, characters tend to refer to XANA as "he" or "it".
Animals Lack Attributes: Averted. Odd's dog Kiwi is most definitely not neutered, as evidenced by the two lumps between his hind legs.
Lyoko looks a lot different in Season 1 than from Season 2 onwards. In Season 2 they removed the lighting effects, made the colours a lot brighter and removed various background details.
The 2D animation changed too, in the earlier episodes the colours were darker and the movement and the design of the characters was different. In Season 2, the colours became lighter and the designs straightened, and in Season 3 the movement of the characters became sharper.
Artificial Human: Played straight with Polymorphic Clones; eventually subverted with Aelita.
XANA gets an A for creativity with this one, turning a teddy bear into a giant, murderous monster.
The Season 4 episode "Cold Sweat" introduces the Kolossus, a giant creature in Lyoko, who continues to harass the main cast until the penultimate episode.
Attack Reflector: A tactic sometimes used against the monsters and their laser beams, especially by Ulrich.
Author Avatar: As noted on the fan forum Lyoko Freak, the SubDigital's members bear a striking resemblance to the executive producers of the show.
The Bad Guy Wins: This show is an extreme example. Every season except the last ended with a victory for XANA, and the heroes spent most of the next season trying to undo their loss, only to be handed another crushing defeat at the end of that season. In fact, in the end, it was Franz Hopper, not the protagonists, who took most of the credit for truly defeating XANA.
Bare Your Midriff: A popular trope among Kadic's female students, but in the main cast we have Yumi and Sissi. And Odd for some reason, although he wears a second shirt underneath that covers him up, unless there are coloringerrors◊...
The first example is in "Missing Link", where the Scyphozoa attacks Yumi and steals her DNA code, making her unable to rematerialize. Aelita volunteers to give Yumi her DNA code, unwilling to let Yumi become the same prisoner of Lyoko that she was... But this was exactly what XANA wanted her to do, because if she had done so, Aelita's memories would have become exposed and easier to take. Fortunately, the team stops her in time, and gains Yumi's code back another way. This may have elements of a Xanatos Gambit too. Taking Yumi's DNA gave her the same vulnerability as Aelita (meaning she would vanish forever if her life points ran out) so XANA likely targeted her specifically as part of a back-up plan to eliminate Yumi if the first plan didn't work. After all, he had given a lot of attention to her before. (See Designated Victim below.)
A large part of his plan in Season 4 is a Batman Gambit. William seemed determined to subdue Aelita and throw her into the Virtual Sea; the other heroes assumed that this was simply XANA's way of eliminating her for good until he actually succeeded in "Distant Memory". Franz Hopper appeared to rescue her, at which point a mob of XANA's monsters sprung out and attacked him. It was all part of a plot to lure him into an ambush, as XANA knew he would rescue his daughter. Fortunately, the heroes learned from this, and Aelita was even able to use her Decoy Getaway trick when William tried it a second time.
Beat the Curse Out of Him: In the episode "Valentine's Day", XANA slips Aelita a Hypno Trinket. To force him to relinquish his grip on her, Odd shoots her repeatedly, until she is within an inch of her life. XANA surrenders, as he needs her alive as much as the children do.
Subverted with Odd. He clearly does not have an unlimited supply of Laser Arrows. In the fourth season, however, Jérémie upgrades his Lyoko form so that he has a far greater supply (still not unlimited, but the magazine can hold several hundred at once).
The Trope is played straight in "False Start" where Jim uses a nail gun to fight Xana's monsters, and never has to reload it.
Boxing Lessons for Superman: The Lyoko Warriors go to boot camp under Jim in one episode to get in shape. It isn't much help on Lyoko, but learning to run faster and farther in the real world is quite helpful when faced with physical threats from XANA.
In "Image Problem", Jérémie makes a passing, non-serious remark about the scanners becoming a health problem (in reference to Yumi/XANA being unable to tell the rest of the group what happened before getting devirtualized unconscious). In "Franz Hopper", XANA masquerading as Franz "confirms" that the scanners are having a negative effect... on Yumi.
In "A Fine Mess" (which, as mentioned below, is Code Lyoko's "Freaky Friday" Flip), Jérémie points out that if Odd and Yumi go back into Lyoko and are devirtualised, the program might mess up again and they'd end up with no bodies at all. In season 3, "Nobody in Particular" sees exactly this happen to Ulrich (complete with XANA taking over his Lyoko-bound body...).
Brown Note: The song XANA made in "Killer Music". Causes slowed heart rate, coma(though eyes remain wide open), and a Joker Gas-like creepy smile
Butt Monkey: Odd, Sissi and her gang, and especially Jim.
Aelita goes through the most out of all of the characters, becoming increasingly less naïve, less impulsively selfless, more worldly-wise and much more of an Action Girl as time goes on.
The never-seen XANA. Initially, all he tries to do is wreak havoc with little to no forethought. From season two onwards, he has clear objectives which he puts a lot of thought into fulfilling. In addition, he becomes more powerful with each season.
Sissi gets a lot as well. In "Frontier", she can't stand the thought of helping Yumi, and insists that Ulrich date her for several weeks. Later, in "Missing Link", she's prepared to help Yumi for no reward whatsoever. Her role in the two-part prequel further helps develop her character, her relationship with the heroes improves throughout the series, and by the end, her becoming an "official" friend just feels RIGHT.
More subtly, the group as a whole become a lot closer throughout the four seasons. In earlier episodes (especially before Aelita was materialised), the group are often very disjointed to the point where it's questionable if they even like each other. By season four, they've managed to evolve into True Companions (partly out of necessity), and while there are still frequent Teeth-Clenched Teamwork scenarios (Rule of Drama at play), they always forgive each other in the end.
Characterization Marches On: In the first episode, Milly was insecure to the point of coming across as psychotic, getting emotional at the drop of a hat and talking to her teddy bear when she's alone. For most of the series afterward, she's a perfectly normal girl.
Chekhov's Gun: Played straight in episodes like "Cruel Dilemma" (with the one-shot materialization program), "Just in Time" (with Aelita's hair) or "Wrong Exposure" (with the Supercomputer reboot procedure).
Conspicuous CG: Some CG are mixed with the real-world animation, notably computer displays or water effects. In a strange inversion of the trope, the real-world CG effects become more obvious with each passing season (a couple CG door swings in Season 3, for example).
Convenient Color Change: Ulrich's katana usually glows blue when striking or parrying, but in the hand of a XANA-controlled warrior (like a Polymorphic Clone, a brainwashed Aelita, or William), it glows red instead. The color change also happens in reverse during "Revelation" when Ulrich steals his Doppelgänger's katana and kills him with it.
Despite Euro coins floating about, hacked military databases emblazoned with derivatives of the French flag, and even a frigging zoom in from a satellite showing exactly which country they are in, the English dub is adamant about the show taking place somewhere other than a French suburb. The euros are called dollars. Hilariously, in "Attack of the Zombies", Milly mentions a foreign exchange program with France.
The Cantonese dub for "A Fine Mess" specifies the type of Chinese into Mandarin that Odd speaks to Yumi's parents and Yumi's reaction to Odd's Cat Girl outfit.
The first Tarantula to show up beat the whole team at once. Possibly a Justified Trope due to the computer-game-like nature of Lyoko. Think about how many times you played a game and the first few bosses later show up as common enemies... It might not even have taken a stat hit, it's just that the Lyoko Warriors now know the weaknesses and powers of the Tarantula so all future encounters fall a lot easier.
When the group fights Xanafied William the first time, he devirtualizes them easily.
Also, the first time Ulrich and Aelita encounters the Kolossus, they are devirtualized within seconds. And all it does to take them out is swing its arm.
Averted: The cartoon series was translated into English by the same company that produced the series (MoonScoop), so aside from a feeble attempt at convincing us the show took place in America (calling Euros "dollars", a character proposing an exchange program with France [England in the original], etc.) the English script is fairly faithful.
But played completely straight with the Subdigitals CD, where all but three or four of the songs had their lyrics junked and rewritten for English release, with less than stellar results.
Cut the Juice: During Seasons 1-2, XANA's schemes aim at preventing the heroes from doing this.
Cyberspace: The virtual world of Lyoko, and the Digital Sea in Season 4.
Decoy Getaway: Aelita has used this trick more than once, creating an illusory clone of herself (or Yumi, in one case) to fool an enemy. It has proven effective on Mooks, the Scyphozoa, and even William.
The level of sympathy Sissi is treated with changes from episode to episode. She was mostly sympathetic throughout Seasons 2 and 4, while mostly unsympathetic in Seasons 1 and 3 (though she still had noteworthy moments in Season 1).
Whether or not the gang find Odd's jokes funny.
When the scanners are offline, losing all your life points either: a) does nothing, and you remain virtual OR b) leads to your death.
Tarantulas started this way, but as the Lyoko Warriors gained experience with them, they stopped being so threatening.
Descending Ceiling: This kind of Death Trap is all-too common in Sector 5, with a few The Walls Are Closing In in for good measure. All of the heroes except Aelita falls victim to it at least once, and it happens to poor Odd twice. (The first time, he compares it to being run over by a steamroller.)
Season 3: Possessing her so that she'd enter the Code: XANA and delete the Lyoko Sectors.
Season 4: Throwing her in the Digital Sea to lure out Franz Hopper.
Yumi too, for no plot-related reason. It runs throughout the entire series, but it's most obvious in the first half of season 1 (a batch of five consecutive episodes of her being targeted was dubbed "Pick on Yumi Week") and season 3. Of course, maybe XANA does have a logical reason for wanting to "pick on Yumi": she is the Cool Big Sis figure of the team, the most mature of the group, Ulrich's crush (and nearly as good at fighting as him), the least enthusiastic about fighting XANA (she was reluctant to do it in the pilot, and was the most willing to shut down the computer in season 4 finale) and an isolated target due to her living with her parents whereas the others are all boarders at Kadic. This not only makes her a much easier target than the others, but also means something happening to her will easily crush the morale of her teammates. Given the manipulator XANA is, it makes sense.
Deus ex Machina: In "Cruel Dilemma", Odd drops some candy on Jérémie's keyboard, which somehow types out the exact line of code he needed to finish his materialization program. This is, however, portrayed as not entirely positive: the code seems to work, but Jérémie can't check, edit, or duplicate it because the dropped candy also caused it to compile, and some angst is had in the course of the episode as a result.
Dumb Muscle: Nicolas, albeit with more emphasis on the "dumb" part of the description.
Early-Installment Weirdness: Not only is Season 1 almost completely different to the rest of the series, complete with a Strictly Formula format for all but the two-parter at the end of the seasonnote On the DVD release, the episodes are out of order despite being numbered in the title cards, but the very earliest episodes also feature some strange nuances. The voice acting is very different, for a start (Odd and Sissi had different voice actors, and Jérémie's voice actor hadn't found the right pitch for the boy yet), and certain aspects of Lyoko act differently, such as Ulrich's clones being able to fight (rather than just being decoys), and Megatank lasers not being one-hit kills.
The gang cooperating with XANA's monsters to destroy the runaway "Marabounta".
Jérémie and XANA in "Common Interest".
Enforced Cold War: In Season 1 and Season 2, destroying the Supercomputer would both destroy XANA and kill Aelita, so actually destroying the Supercomputer or Lyoko is out for both sides. Afterward, XANA can attack it.
Epic Fail: Without exception, Jérémie causes a disaster whenever he tries to do something outlined in Franz Hopper's journal — like when he tried to do so in "Marabounta" and a few other episodes. He eventually attributes this to Hopper being such a genius that his notes are just too complicated for him to comprehend properly.
Yumi at the dance during Aelita's first stint as a DJ in "Final Mix".
Everybody Knew Already: Pretty much every student knows that Odd is hiding Kiwi in his room in defiance of school rules, even though the faculty are clueless. Sissy threatened to tell on him in one episode, but she apparently decided against it.
Evil Cannot Comprehend Good: XANA shows this in "Ghost Channel" when he tries to trick Odd, Urlich, and Yumi by posing as Jérémie. When Jérémie shows up and it turns into a case of Spot the Imposter, XANA insists that Jérémie wouldn't come to Lyoko because he'd be too afraid to; however, this is actually what gives him away, because the rest of the team is certain that Jérémie would do so, despite being afraid, if their lives were in danger. Note that XANA does eventually prove capable of Comprehending Good in later episodes, and even trying to take advantage of it. See Batman Gambit above.
Evil Only Has to Win Once: Played straight in Season 1, subverted in Season 2. Afterwards, there are multiple victory conditions for XANA, and not all of them lead to a final Game Over.
Fanservice: Oh God, the fanservice. Nearly every main character has had a shirtless/underwear scene of some sort. And yes, it's all in the dub. Which was run on Cartoon Network. In the afterschool slot. With a TV-Y7FV rating. Remember, though, this is a French television series. The United States (viewing area of Cartoon Network) views nudity and partial nudity as much more risqué as opposed to the French culture.
Despite this, Aelita's first two civilian outfits include Magic Skirts; for reasons known only to MoonScoop, she has never had an underwear scene (except that time her heart was restarted and she appeared to be wearing a slip). Instead, she is seen stepping into a shower and standing under the water in Season 4.
** There is even Sissi in her cheerleader outfit, with several frames of animation in which you can clearly see up her skirt (she's sitting down and crossing her legs). She is also seen walking around her room in her underwear in early episodes — including the first episode, 6 minutes in; how's that for quick to please?
Foreshadowing: The show is very clever about its foreshadowing, repeatedly putting in hints that will only be glimpsed in hindsight. For an example, one episode has Yumi's parents fighting... the next, Yumi's dad lost his job and they might be going back to Japan. The prequel has a couple references to the first episode as well, which would be counted as foreshadowing if the prequels had aired before season 1.
Conducted in Season 1's "Cruel Dilemma" when Jérémie (with assistance from Odd's candy) creates a one-shot program to materialize Aelita, but must use it to extract Yumi from the Digital Sea.
And then the tables turn in Season 4's "Hot Shower", in which Aelita gets herself devirtualized to make XANA choose between letting an incoming asteroid destroy the Supercomputer (and her with it) or destroy it with the good old Kill Sat to give both of them another day (as XANA needs Aelita to lure out Franz Hopper).
Future Spandex: In Season 4, the new Digital Avatars of the heroes have a serious Future Spandex look. They were apparently designed by Jérémie, a 13-year-old Teen Genius (except for William, who got his custom-made by XANA). You have to wonder what was going through their minds... though on the other hand, maybe that makes it a Justified Trope.
Genius Bonus: invoked In "Contact", it's possible to notice that the Franz-possessed Sissi is speaking backwards. Using software (like a DSi's sound function) to play it backwards reveals the message "I've come to contact you, I'm Franz Hopper. I can help you!" at the very start of the episode, similar to the Norwegians in The Thing (1982).
Getting Crap Past the Radar: Tons of it, though it's worth noting that the English dub was produced by MoonScoop alongside the original French, rather than it being dubbed by an American company. They aren't Getting Crap Past the Radar, they are the radar. Still, Cartoon Network could have edited out some of the more blatant stuff if they really wanted to. Some of this may be simply Values Dissonance, though. What could be considered racy in North America would be deemed completely innocuous by the French. (That still doesn't excuse the Sensual Spandex in Season 4...)
Giant Enemy Crab: Krabes. It should be noted that their Weak Point is on the top of their shells, not under them. Under them is where their pile-driver laser is. Still, they have been stabbed there, even if it didn't do the job.
The Greatest Story Never Told: This was lampshaded a couple of times throughout the series. The group has been risking their lives fighting XANA and saving the world for years, and no one will remember it but themselves. A minor example occurs in "Maiden Voyage", where the incredibly nonathletic Jérémie scales the dorm roof of Kadic to get to his room due to a fire safety drill prohibiting access to the building. Odd (jokingly) correctly guesses that Jérémie did that, but nobody actually believes him.
Grey Goo: Jeremie inadvertently nearly creates this kind of disaster in "Marabounta", when he tries to use Franz Hopper's journal to use a weapon to destroy XANA's army. Naturally, the thing goes out of control (leading to a chilling scene where Yumi is Eaten Alive by the thing and devirtualized trying to protect Aelita) forcing XANA to enter an Enemy Mine situation with the heroes to save Lyoko and Aelita (as he still needs her alive at this point). This was one of several times that Jeremie made a mistake using Hopper's notes, which were clearly too complicated for him to understand. (It wouldn't be the last time.)
He Who Must Not Be Seen: XANA might qualify, being a bodiless computer program who never physically appears to the heroes except on two occasions (once taking the form of Jérémie, and the other time as Franz Hopper). He could also be considered The Voiceless as he did not communicate with the heroes at all, except for those two times plus once leaving a text message on Jérémie's phone.
Hoist by His Own Petard: XANA creating the Kolossus and revealing that he had hundreds of Replikas around the world defeated Team Lyoko for one mission, but it also made it clear to Jérémie and the other Warriors that they couldn't stop XANA just by knocking out his Replikas, forcing Jérémie to develop the Multi-Agent Program.
Holographic Terminal: All over the place within towers and the Celestial Dome in Sector 5 (itself neither an actual dome or really all that celestial). The Supercomputer proper also has a Holosphere in the middle of the room, but it's just there for fluff.
Ulrich's Overbike (can hover, but doesn't normally)
Hulk Speak: William and other XANA-possessed humans are quite monosyllabic (Polymorphic Clones even moreso). At least, once the influence has become obvious. (And sometimes, even using words is beyond their means. "YAAAAAAAAAR!") As season 4 goes on, William gets more talkative in XANA mode, eventually being able to speak in complete sentences.
Human Popsicle: Well, sort of... Aelita was trapped inside the Supercomputer for around ten years, during which time she didn't age at all.
Hypnotize the Princess: Aelita falls victim to this several times, especially in Season 3. Across the whole series, it's happened in exactly six episodes: "Saint Valentine's Day", "Lyoko Minus One", "The Pretender", "The Secret", "Double Trouble" and "Wrong Exposure".
Imperial Stormtrooper Marksmanship Academy: XANA's monsters rarely hit the heroes... even sometimes at close range or when they are stationary targets. Odd and Yumi also appear to be graduates in the early seasons, though that may just be Frelions acting as Goddamned Bats. Although it depends on Rule of Drama. When the Tarantula was first introduced, it was very accurate and brought down the whole team.
Impostor Exposing Test: By Season 4, the kids sometimes check out the eyes of those they suspect to be Polymorphic Clones to see if XANA's symbol doesn't briefly flash.
Inane Blabbering: Some victims of XANA's latest attack, occasionally, especially Sissi or Jim.
Indy Escape: The rolling Megatanks sometimes force the heroes into this.
The show starts without a Pilot or Premiere episode, almost a year after the fight against XANA began. There was no explanation of how Team Lyoko discovered the Supercomputer, programmed their virtual avatar appearances and abilities, or came to meet Aelita, until a two-parts prequel in Season 3.
Many episodes also begin in the middle of the action on Lyoko. This strongly implies that not all of XANA's attacks are shown, several happening off-screen. There is even a How We Got Here in "Bragging Rights".
Suzanne Hertz: Jim! You're worse than the barbarians who burned down the Alexandrian Library! Jim Moralés: Why, thank you, Suzanne!
Also, in "XANA's Kiss". Odd is having his ass handed to him by a polymorphic clone that keeps changing shape, currently assuming Jim's appearance. Odd tells it, "Hey, XANA, if you're going to keep changing appearances like that, do me a favor and turn into a wimp next time." XANA's response? He has it turn into a duplicate of Odd. Of course, being the Deadpan Snarker he is, Odd quickly comes up with a witty comeback to that: "Oh, no. Not him. I know his kind. Small, but tough as nails." (Unfortunately, he's right. It starts to pummel him even worse.)
Ridiculously overused in the first season, in which virtually every time XANA is defeated with approximately 0.001 seconds to spare; at one point, a laser beam is halted inches from Yumi's face when the "Code: LYOKO" activated. Later seasons toned this down a bit. Actually a Season 1 episode title, although not the Trope Namer.
A role reversal ends up occurring in "Lab Rat" when XANA uses William to enter and steal control of the tower the gang is using to translate to the site of the Replika supercomputer with the XANA code. Odd is shown to be a mere one syllable away from firing the shot that would destroy that supercomputer when he and Aelita vanish from the site.
In episode 29, "Exploration", Ulrich voices his desire to just shut down the Supercomputer and be done with it. This leads to the following comment from Odd:note Note, though, that "you missed an episode" is a perfectly valid French expression in everyday conversation. Still this trope, here.
Medium Blending: The two worlds of the show are depicted in completely different mediums, as to make very clear the transition from the "real" world to Lyoko. Ironically, the "virtual" world rendered in CG has naturally a more "realistic" look than the standard animation of the "real world". But you get used to it.
Mercy Killing: The Lyoko Warriors use a non-lethal variant of this many times when one or more of them needs to devirtualize themselves in a hurry and Jérémie can't do it for some reason. Basically, it involves a teammate turning his weapon on the other in order to reduce his or her life points to zero (or two doing it to each other simultaneously, in extreme cases). More than once, Odd and Aelita have saved someone from falling into the Digital Sea this way.
The Men in Black chasing Franz Hopper in the flashbacks.
And the two unrelated (?) secret agents in "False Lead".
Mind-Control Eyes: All of XANA's creatures have his eye-like symbol. Those he mind-controls have their irises and pupils replaced with this symbol. Doesn't happen all the time, but they've been caught by flashing the eyes unnecessarily.
Missed the Call: In aforementioned prequel episode, it was Sissi, not Yumi, who found the factory with the others. She even planned on entering the "game" later, but before she did XANA got loose for the first time, and Sissi tattled because this was getting too real. As a result, the whole group was nearly arrested, and the others unsurprisingly agreed to keep her in the dark after returning to the past. Sadly, Ulrich decides to be a jerk to Sissi about it even though she doesn't remember what her mistake was, resulting in her becoming the group's Alpha Bitch nemesis for a good long while.
Missing Mom: Anthéa Hopper, whose role in this mess has yet to be explained. (She may have been abducted by the The Men in Black, but no-one knows why.) The fact that Sissi doesn't have a mother is completely ignored.
Addressed in "The Chips Are Down", when Ulrich uses the Reset Button to rig a lottery ticket and win several million euros. It's completely possible to do this, but not a good idea since each Return to the Past makes XANA stronger. At the end of the episode, Ulrich donates the proceeds to an African development project, preserving the series status quo.
Played completely straight when Ulrich, being a Virtual Ghost at the time because of Jérémie's latest bit of mad science, possesses Jim to use him as a pawn to keep himself from being knocked down to a remedial class.
Mutual Kill: One of Yumi's victories over Evil!William is this, nailing him with her fans in a Boomerang Comeback just as he's devirtualizing her.
My Skull Runneth Over: Jérémie tries to use the Reset Button's quantum components to enhance his own brainpower in Season 2. Bad idea to start with, worse because XANA slipped him bad code.
Near Villain Victory: This is seriously the case in "Hot Shower". XANA's plan is so perfect, Jérémie actually gives up. Really! The heroes only triumph because Aelita hedges all her bets on a hunch that XANA will abort his plan if it will result in her death (meaning he'll lose access to Franz Hopper); fortunately, her hunch pays off.
Neuro-Vault: Lyoko's keys were hidden inside Aelita's memory.
Never Bring a Knife to a Gun Fight: Seriously inverted with Ulrich. You'd think a Jedi Master taught him how to use a sword the way he can deflect laser beams with it. He even does so in the real world once!
The kids go to an abandoned factory every episode. There's never any presence of demolition crews, and the plot only revolves around saving the factory from destruction when it's some attack from XANA — at least in the animated series. The non-canon spin-off comics have one story with a demolition crew about to raze the Factory, before being thwarted by the kids. Ironically, the actual factory that the series' was based on was demolished in 2004.
There is also the Hermitage, a posh house in the woods that is left abandoned for 10 years. However, there are some hints of squatting (vandalism, tags on the walls...) and since the first time Team Lyoko visited it XANA was playing poltergeist, maybe this chased any squatter earlier and gave it a Haunted House reputation.
Never Recycle Your Schemes: XANA, with a few exceptions (like multiple uses of polymorphic clones), never tries the same attack twice. Sometimes, especially in the first season, the group takes action to prevent him from repeating a scheme, but other times you have to wonder why he doesn't just repeat an attack with a few modifications, considering the kids are so often only Just in Time to defeat him, sometimes within a few seconds.
Nice Job Breaking It, Hero: Sissi's entire Alpha Bitch personality is a result of Ulrich, who was more of a Jerkass back then, mistreating her at the end of the pilot for something she had no memory of doing and shunning her away from him and his friends. To his credit, in the series finale he's the one to mend bridges and let Sissi join the group.
Nice Job Fixing It, Villain: XANA occasionally ends up helping the group by accident. For instance, in "Is Anybody Out There?", Odd gets devirtualised after he finds the activated tower. This happened to be extremely fortunate, because if it hadn't happened, no-one would have been around to type in the code "Scipio", and XANA would have stolen Aelita's memories!
Given the amount of times Jim would "rather not talk about it", the man seems to be made entirely of this trope. It is slightly subverted in the episode "I'd Rather Not Talk About It" (of course), in which Jim does talk about it, although it's only with Jérémie and we don't get to hear it. Nevertheless, it causes Jérémie to gain a healthy respect for Jim. Even better, at a skate demo, when Jim showed he was knowledgeable about skateboarding, it was a time when he did want to talk about it; rather, he was a little busy and didn't have time to talk about it right then.
Two minor ones are also referred to in the episode "Crash Course" (What exactly DID happen in the gym and at the swimming pool?). Three if you count whatever led to the protocol moniker "Big Fat Cheese-Head".
Jérémie's one-shot materialization program in the first season. Saving a copy to a disk is apparently out of the question.
Lyoko's temporary destruction is a subversion. While the Lyoko Warriors didn't possess a backup, Franz Hopper did, which he happily provided (it wasn't all of Lyoko, just the core, but it gave them a base to restore the rest on). In this instance, at least, one could reasonably assume that storing a backup copy of Lyoko would take an obscene amount of storage space, given the revolutionary hardware hosting it.
Nothing Is Scarier: XANA is a Third Variation Example; somewhat subverted because the heroes know that he's there and he's trying to kill them. Still, he's an enemy that they can't see or hear, but one that is still more terrifying than any that they can.
Only Six Faces: Eyebrow shapes and hairstyles vary, but the all the faces are pretty much the same. Except for the adults like Jim and Delmas.
Orgasmic Combat / Looks Like She Is Enjoying It: In the English dub, a lot of the grunts, yells, and cries of pain made by Yumi and Aelita just can't be interpreted as anything but sexual moans. It crosses from mediocre acting to ludicrously bad, however, when expressions of horror at virtualisation errors sound like orgasms.
Pac Man Fever: Largely averted; not surprising, since the relationship between kids and video games is a big inspiration for the series. The fictional video games discussed in the show are realistic for modern games (though rarely seen on-screen). However, the "penguin cup-and-ball" game played by Jean-Pierre Delmas do use Pac-Man music — but here it's more of a shout-out.
The Password Is Always Swordfish: The password to deactivate the towers is the name of the virtual world. However, only Aelita can enter it properly, because she holds the keys to Lyoko.
Phlebotinum Breakdown: Statistically rare considering how often the scanners are used; nonetheless, sometimes the problems faced by the heroes aren't due to XANA's sabotages but to some bug of the Supercomputer or wrong manipulation. Notably:
A botched virtualization that stuck Jérémie in the limbo between Earth and Lyoko in "Frontier".
Switching Odd and Yumi's minds in "A Fine Mess".
Toying with a teleportation power that results in three Odds in "Triple Trouble".
Melding Kiwi with Odd in "Dog Day Afternoon".
A random bug causing spontaneous devirtualizations in "Hard Luck".
Really, just about any time Jérémie tries out a new program he's hacked together, it will screw up somehow.
One appears on Lyoko whenever a monster or hero falls in the Digital Sea (save for William).
Also occurs at the beginning of a return to the past sequence, when an expending pillar of light bursts from the holographic display in the lab.
Playing Sick: A standard excuse to get out of class and go save the world. Oddly enough, the teachers almost always fall for this, except on one occasion. Of course, they don't remember most previous incidents thanks to the Return to the Past.
Another episode put it even further by centering morality around Yumi alone: in this episode, Odd inadvertently publish a embarrassing photo of Yumi in Kadic's newspaper, understandably making her pissed off. Scared of Yumi's wrath, Odd convinces Ulrich to take the blame for him without telling what the blame is. After Ulrich learned it and ended up with Yumi angry at him, he attempts to convince Odd to tell the truth to her, until Yumi assumes he did it because of their Unresolved Sexual Tension and forgives him, causing him to keep the silence after all. In the end, Odd finally tells the truth to Yumi, and how does she react ? By being pissed off again for them "tricking her" and taking her revenge on both Ulrich and Odd by publishing a compromising photo of them in the newspaper. Yeah, because Ulrich was so nasty by taking wrongly all the blame for the sole sake of helping his best friend...
The Factory is based on an old Renault plant and headquarters located in Boulogne-Billancourt that was demolished in 2004.
Red Herring: In Season 4, the fourth Navskid (obviously prepared for William) ends up never being used.
Reset Button: Nearly every episode, via Mental Time Travel. The main kids aren't affected by it, but students and faculty who discover them (and become allies or enemies) go back to being ignorant. It's used more sparingly in the second season, after they discover that using it empowers XANA. Even after the link to XANA is severed at the end of Season 2, the Return to the Past is still employed conservatively, if mostly to prevent mucking with the narrative (see Just in Time above).
Rivals Team Up: In "The Robots", the team enlists Hervé's help to create a device to fight XANA's androids, and he actually does a pretty good job. Unfortunately, the Return to the Past trip erases Hervé's memory of the event, and ruins any chance of them becoming friends permanently.
Robo Cam: XANA's monsters, robots, Polymorphic Clones, and Specter-possessed people.
Robot War: XANA is preparing one, but is shut down just as he starts production.
Role-Playing Game Terms: Characters under attack by XANA's monsters in Lyoko will lose Life Points, de-virtualizing when they reach zero.
Sarcasm-Blind: In "Final Mix", Sissi is banned by her father from going to the dance party because she didn't study for her exam. Naturally, she ignores this and goes to the dance anyway. Cue the following exchange with Nicolas:
Nicolas: You snuck out? Sissi: No, no. My father said, "You're gonna repeat the year, but it's no big deal sweetie. It doesn't mean you can't have a good time." Nicolas: Is that what he said? Sissi: (agitated) Oh you're such an idiot! Of course I snuck out, what do you think?!
Saying Too Much: The fake Franz Hopper criticizes Jérémie about letting his diary be ruined, something the real Franz Hopper would have had no way of actually knowing, thus revealing himself to be XANA in disguise. This, however takes a bit to register in Jérémie's mind because his whole group effectively turned against him.
Scenery Porn: Frédéric Perrin's work on the backgrounds used almost endlessly in the animated sequences fits this to a capital "T".
The first time that the party dematerialized one of their number with their weapons, it looked like this, with Yumi sounding grimly resolute and Badass when she suggested it. Later on, as the gang becomes more experienced, it becomes more of an accepted way of salvaging the mission when Jérémie is unable to act.
Aelita intentionally invoking Code: XANA and nuking the Ice Sector in "Sabotage", saving the rest of the Supercomputer.
In one episode, Odd comments on being great with women; immediately, a girl walks up to Odd and smacks him; he has just finished commenting on "not knowing what this is about" when another girl, seeing the first, walks up and smacks him for being seen with the other girl. Odd then admits he might have deserved that one.
Sorcerer's Apprentice Plot: Invoked at one point, when Franz Hopper accuses Jérémie of being "the sorcerer's apprentice" and screwing everything up by using the Supercomputer. Actually, it's XANA trying to get Jérémie out of the way for his latest plot.
Spell My Name with an S: Xana, XANA or X.A.N.A.? Jeremy or Jérémie? Sissy or Sissi? Herb or Hervé? Antea or Anthea? And should you use the accented letters? This one'll put fans up in arms faster than tying Ulrich or Yumi down to a permanent love interest.
Spike Balls of Doom: Three of these defend the International Space Station taken over by XANA in Season 4.
The first occurrence was with XANA himself impersonating Jérémie in "Ghost Channel".
Aelita could tell Jérémie apart from his double in "XANA's Kiss". It happens a second time in the same episode: Odd has to decide between the Polymorphic Clone and Yumi, and figures it out because the real Yumi called him "pea-brain".
Jim isn't so lucky with his nephew Chris in "Opening Act".
Happens a few times with Ulrich's katanas; sometimes for himself, sometimes for other characters.
Everyone also seems to use William's BFS for this whenever he gets it stuck in a wall.
Stock Footage: To the point where even the first episode has reused scenes (see Garage Kids below). It gets really obvious at certain points. A good example is Season 2, where the footage from Season 1 of Aelita deactivating Towers is used, despite the Art Evolution having taken place, with the difference between the old and new footage very clear. It's until Season 3 where new footage of Aelita in the Towers is used, showing her deleting the sectors of Lyoko. Even then, some Season 3 episodes still use the Season 1 footage when she deactivates towers. In addition, battle sequences on Lyoko are very frequently recycled between episodes.
A variation is used where Aelita's friends threatened to kill her before the Scyphozoa could Mind Probe her (which would kill her too), forcing XANA to order the monster to release her.
In "Hot Shower", Aelita sets up a situation where the Supercomputer can't be destroyed without killing her, and XANA aborts his Colony Drop attempt (as he needs her alive, so he can lure out Franz Hopper from the Digital Sea.
Something strange happens around the school (blatant Foreshadowing optional). → Jérémie thinks it's XANA, Odd doesn't. Heads up: It's XANA. → Jérémie and one or two of the Lyoko Warriors go to the factory. The remaining one or two of the three must stay behind in danger to heighten the drama. → The virtualized Warriors fight 3-5 monsters, while Aelita takes her sweet time getting to the tower. (Life Points are referenced only for Rule of Drama as well.) → The in-danger team members are saved Just in Time by the tower de-activation plus a Return to the Past. → The team returns to a scene from the beginning of the episode, usually Played for Laughs.
Super Drowning Skills: Falling into the Digital Sea is immediately lethal for the Lyoko Warriors or the monsters. The backstroke in ordinary bodies of water, however, is perfectly fine for the heroes (but terrestrial monsters can't swim). Although it is confirmed in Season 4 that the Digital Sea is not a literal sea, but rather the edge of Lyoko. Also, it's implied in "Cruel Dilemma" that the person wouldn't actually die, but simply be trapped, unable to return.
William is the Trope Namer, as he uses this power extensively.
Also a talent for Polymorphic Specters.
Superstition Episode: In the episode "Hard Luck", Odd accidentally breaks a mirror. Ulrich tells him he'll get seven years of bad luck. Odd doesn't believe it and rants about how various superstitions are ridiculous. However, a series of unfortunate events plague him and eventually the rest of the team starts to consider him bad luck. At the end of the episode Odd finally admits he is jinxed, only for Aelita to tell him jinxes don't exist and he has to wait for his luck to change. It does.
Taken for Granite: XANA tries a something like this in "Triple Trouble", unleashing a fog on the whole city that can do it. (Which is sort of strange, seeing as it more resembled his MO from the first season, rather than anything related to his goal in the third.)
Took a Level in Badass: William initially appeared to be a secondary character to build tension for Yumi and Ulrich's relationship, merely getting in the way and even stalking Yumi. Then he enters Lyoko, where he gets a giant sword, although he gets an evil makeover as well after being possessed by XANA. He even has awesomemusic accompanying his fights throughout Season 4.
Too Spicy for Yog Sothoth: Aelita uses her Decoy Getaway trick to escape the Scyphozoa. The monster is fooled, and tries to use its memory-draining powers on the clone... which results in it becoming sick.
Traveling at the Speed of Plot: The amount of time until XANA's current plot completes is always just long enough that the Lyoko Warriors will beat it with a couple of seconds to spare, if that. Same with the Sector 5 countdown or the second layer of the Core shield. They rarely run out of time, either; if XANA wins, it's nearly always by defeating the heroes, not just running out the clock.
Weapon of Choice: According to Jérémie, the gang's weapons were selected based on subconscious data extracted in their initial virtualizations.
Wham Episode: "Final Round" and, to a lesser extent, "The Key".
What Happened to the Mouse?: Mister Puck is demoted from the mysterious subject of Aelita's nightmares to a doll in her flashbacks. Perhaps the latter was his intended role all along, but the scenes in which Aelita sees related visions while awake in the episodes "New Order" and "Mister Puck" would suggest otherwise.
What Is This Thing You Call Love?: Subverted; when Aelita is first materialized she often gets confused by emotions such as embarrassment, and by physical feelings such as hunger. In "Cruel Dilemma", though, Aelita is confused when Jérémie starts blushing when she says, "We can finally be face to face in the same room, touch each-other, and even kiss."
Ulrich suffers from vertigo every now and then, and some spots involving him and high places are particularly rocky. It's not that he's afraid of heights, it's that high places are more likely to agitate his condition. He tries his best to suppress this, though.
Aelita has a bad thing for wolves. They frequently show up in her dreams or hallucinations.
Will They or Won't They?: Ulrich and Yumi, to such a ridiculous extent that it makes their own shippers cringe. Though the last episode hints that they will. Eventually.
Xtreme Kool Letterz: Kankrelat, Blok, Krabe, Kongre, Rekin, Kalamar, Kolossus... Justified in-show by Odd coming up with most of these.
You Gotta Have Blue Hair: Aelita's pink hair is sort of justified at first because she's actually a computer program, so her hair could be any color. But then it turns out that she was human after all, so this makes little sense. Especially since, except for Odd's big purple spot (which could have easily been dyed like that), almost everybody else has regular hair colors — but seem to find Aelita's hue perfectly normal. The few exceptions are: Aelita's mom; William's mother (whose hair is conspicuously green); Odd's mother (who has purple hair; the show seems to like applying this trope to moms for some reason); a girl candidate at the Subdigitals' talent audition; and Chris Moralès.
Justifies the phantom pains felt by Yumi, Ulrich, and Odd upon taking damage, since they're non-natives to Lyoko. In one episode, a virus uploaded into the computer by XANA makes it TOO real, with one shot hitting causing immense pain.
Jérémie has also theorized that a person's Lyoko form is reflective of his personality, subconscious desires, and dreams. For example, Yumi's pride in her heritage gave her the appearance of a Geisha, while Ulrich's lionhearted nature gave him the form of a Samurai. (Odd insisted that he never dreamed of "big, purple cats", but it may have something to do with his reputation as a Deadpan Snarker; see Alice Allusion above.)
Camera Screw: The first DS game is very bad about this, especially since you can fall off nearly any platform and have a quarter of the health of that character lost for the effort.
Getting Crap Past the Radar: The game Quest for Infinity has at least one instance. While battling a boss, one weak spot they show is a rather large golden sack-like thing hanging off the monster... Clearly they took cues from the Gonarch in Half-Life.
Ax-Crazy: Eva. Being an incarnation of XANA will do that to a person.
Break the Cutie: Implied with XANA. In the "Mysterious City" flashback, he was a token cutie, while in the present, he is clearly already broken.
Canon Foreigner: About ten of them — Eva Skinner/XANA and Grigory Nictapolus, most prominently. Most of them are featured for a chapter, then disappear.
Compressed Adaptation: Only bits of "XANA Awakens", "Code: Earth"/"False Start", and "Fight to the Finish" still exist in this continuity. Everything else in the show is erased and replaced with the plot that ties those three together, occurring in maybe half the time. The major plots of Seasons 2, 3, and 4 are solved in one battle.