Loophole Abuse/Anime and Manga

Anime and Manga
 * In episode 8 of Code Geass R2 (second season), Zero accepts Nunnally's plans to restart the SAZ (Special Administrative Zone, where there was no distinction between the Britannians and the elevens, formerly Japanese), and privately makes a deal with the Knights of the Round that he would be exiled instead of executed for his most recent terrorist actions. Suzaku agrees to the plan, and then after they announce Zero's exile, the Black Knights create a smokescreen in the area with 1 million Japanese, during which they all don Zero costumes. Since they were all Zero, Suzaku would either have to let them all go, or else order another massacre which would no doubt caused more rioting and rebellion in Area 11, as happened accidentally the first time around at the end of Season 1.
 * In Beyblade there is a rule that you can't attack another player, but it doesn't count if you can't see the weapon. Bryan was able to seriously injure Ray by attacking him with air control.
 * Ranma 1/2
 * The rules for Martial Arts Rhythmic Gymnastics clearly state that the only valid method of attack is with a tool. Barehanded (or barefooted) contact is strictly forbidden and can result in immediate disqualification. However, this doesn't stop Kodachi from modifying her gymnastics tools into clubs with retractable spikes, ropes which snap into iron rods, razor-sharp hoops, and explosive balls... or simply snagging whatever she can wrap her ribbon around (including Kuno) and hurling it back at her enemy. Of course, it doesn't keep Ranma from using anything she can get her hands or feet on (including Ryouga Akane's pet piglet,) or demolishing the ring itself with kicks and punches. Kodachi using her bokken-wielding brother was also considered a valid attack.
 * It goes one step further - the rule forbids attacking your opponent without a legal weapon.
 * In both versions this is how Kodachi "justifies" remaining the first true member of Ranma's Unwanted Harem (not counting Akane Tendo, on virtue of her being the Official Couple), despite having promised to give up on Ranma if she lost the match. Having agreed to "abandon her present affection for Ranma", she explains that she now "burns with entirely brand new passion for him" when she tells girl-type Ranma that she will be coming after Ranma again.
 * In anime version of the climax to the Phoenix Pill saga, Ranma needs to win a combination of downhill race and running battle in order to win the pill that will undo the Full-Body Cat's Tongue point that keeps him locked in female form. Unfortunately, he's never skied before, so he stinks at it. Akane mercifully throws him some snowshoes and points out there's no rule saying he has to ski down the slope, just that he has to reach the finish line first with an unbroken miniature snowman. Ranma takes things a step further by soon after hitching a ride on the back of an angry black bear.
 * In ~Mamotte! Lollipop~, female lead Nina is distressed to learn that the contest for gaining a professional wizard's license has no rule against killing human beings (i.e. her) to obtain the Magic Pearl.
 * Revolutionary Girl Utena: Ain't no rule that says a girl can't wear a boy's uniform! Apparently there's no rule that says it has to be the same color as everyone else's, either!
 * Fruits Basket: ...and vice-versa.
 * Dragonball's Greatest Under the Heavens martial art tournament's regulations are full of loop holes. If you don't touch the floor out of the ring, you can fly, grow, become a giant monkey, multiply yourself, use fire-guns, stink and a long etc.
 * They do have one moment of Obvious Rule Patch: Goku uses the Nimbus (a controllable semi-solid cloud) to return to the ring after being launched out of it (this was before he could fly). The officials find themselves in a dilemma: Goku didn't technically touch the ground outside the ring, but do clouds count as "out of the ring" if one can stand on them? They finally allow it this once, but also state that if Goku does that again, he'll be disqualified.
 * Similarly, in the Cell Games, Cell decides to eliminate the possibility of either side losing by a simple ring-out by destroying the whole arena.
 * Pretty much the whole point of ninja training in Naruto; one is supposed to barrel on through the rules.
 * The written part of the Chuunin Exam is one example. The test consists of ten incredibly difficult questions and cheaters are disqualified after being caught cheating a few times. Similarly to the real life Spartan example below, the true purpose of the test is not to determine the candidate's knowledge, but to test their ability to gather the required information without being caught cheating. Naruto accidentally discovers a real loophole in the written test: you only fail if you're caught trying to cheat, but the test is played up in a way that there is no penalty for not trying at all.
 * Naruto also does this with training which does not involve rules—any time he can't get past a certain stage of a training he always finds some clever way to bypass it. For instance, Jiraiya figured he couldn't get past a point in the Rasengan training because he couldn't randomize the rotation of chakra with one hand—so Naruto just used his other hand to make the rotation random himself.
 * His shadow clones are Loophole Abuse incarnate. Any time he needs to do something that can't be done (either at all or in X amount of time), shadow clones help circumvent the rules. It's how he managed to master the Rasengan (use a clone to focus the chakra) and then later evolve it into the Rasenshuriken (a second clone injects Wind-elemental chakra).
 * Liar Game. The day Akiyama actually plays a game without looking for loopholes will be the day of the apocalypse.
 * Of course, deducing the hidden meanings and ramifications of the rules, then exploiting them to win is the wholly intentional part of the eponymous game.
 * During Eclipse's song-length game in Basquash, the rules are that the game shall run until the end of the song. Rouge is "hurt", trying to force defeat on Dan's team, but Flora exploits a loophole when she reveals that Eclipse don't have to be the ones singing. She leads the crowd in song, letting the game finish.
 * In Bleach:
 * Following a good ass kicking by Ichigo, Byakuya Kuchiki becomes more willing to bend the rules a bit. This is made especially clear in the Arrancar / Hueco Mundo arc, where he was sent to bring back Rukia and Renji to the Soul Society, Yamamoto having forbade them from infiltrating Hueco Mundo to rescue Orihime. He notes that while he was ordered to bring them back, he had no orders on what to do after that. He actively provides them with desert-proof cloaks to wear and helps them return to the human world and then looks the other way when they make contact with Urahara in order to get to Hueco Mundo.
 * He abused this clause again when he was "facebooked" by Tsukishima's power. Tsukishima expected that thanks to Byakuya's honor, he will not be defeated. Byakuya replied (after punching through him) that it doesn't change the fact he is Ichigo's enemy.
 * From the Amagai Arc, when the Gotei 13 is ordered to apprehend Ichigo, Byakuya tells Renji to lead the 6th squad, saying that he's going to keep his nose out of the whole affair. In other words he said " I can't break the rules and help Ichigo, but I can turn over all my authority to my crazy vice-captain who will do just that, and then I pretend I never saw it coming."
 * Uryuu sort of does this in order to join Ichigo and Chad to go to Hueco Mundo. In return for his father agreeing to help him get his Quincy powers back, Ryuuken made Uryuu promise that in future, he would no longer associate with the Shinigami or any of their associates. Uryuu manages to bend the rules thanks to some lucky circumstances: Ichigo is not a true Shinigami, just a substitute Shinigami, and, by Kisuke's wording, one that has been abandoned by Soul Society. In other words, neither a Shinigami nor one of their associates. Ichigo even calls it "twisted logic".
 * The Davy Back Fight of One Piece allows the team that wins each match to pick a member of the opposing team and force him or her to join their crew. In the third round, Nami considers choosing Foxy, who is set to compete in the Combat event against Luffy, so that they win by default in the third match and can easily get Chopper back. While some members of the opposing team hypocritically protest (they had already done the same thing to one of the three Straw Hat set to compete in the second event), Robin notes that this is legal, but none of the Straw Hats want Foxy with them.
 * After an Obvious Rule Patch and a boxing match, 497 Foxy members are forced to join Luffy's companions. Luffy's ship, the Going Merry, cannot carry that many people, besides he doesn't want them anyway. However, a pirate captain's orders are absolute, and there's no rule a captain cannot assign his crew a mission to be dismissed.
 * A far less humorous example comes up far earlier on. In Nami's backstory, she makes a deal with Arlong; If she works as his cartographer, he'll sell her back her village and release her from service if she can raise 100 million beri. Years later, she's only 7 million away from that goal, but Arlong doesn't want to let her or her village go, so he has a corrupt Navy officer confiscate her stash. When Nami accuses Arlong of trying to break the deal, the bastard smugly retorts, "When did I break my word?"
 * In the third sound stage of the first season of Magical Girl Lyrical Nanoha, Fate is unable to contact Nanoha in real time because of restrictions placed on her for her trial, which is why they exchange video letters to see each other's faces and hear each other's voices. During a celebration of the anniversary of Fate making a contract with her Familiar Arf, Lindy allows Fate to see a video link of Nanoha launching Starlight Breaker fireworks and Amy suggests that the video, lagging behind by 0.05 seconds, is not technically real time.
 * Higa of Sekirei pulls this, bringing extra Sekirei to the third match, stating that it's okay as long as they don't fight.
 * In IGPX Immortal Grand Prix, on two separate occasions teams get away with doing things that logically should never be attempted, as there was no rule covering it. The first time, a team creates a tornado that was just as likely to get them killed as it was to win them the race. The second time, another team uses devices to take control of their opponents' vehicles. The rules are amended both times to stop them from repeated abuse, but they get away with their victories. The second team would also later reveal (in the final race) that their vehicles were actually Combining Mecha that could effectively block the entire track, but they lost that race.
 * Yu-Gi-Oh:
 * Yugi exploits an infinite loop combo that Marik/Strings used to fill his hand... to mill his own deck. Mind you, this stunt is not indicative of how Revival Jam and Brain Control actually work in the real card game, to say nothing of the fact that God Cards don't have real effects for a reason.
 * Similarly, the Legendary Dragons in the Doma Arc can do freaky infinite-loop tricks because they're already logistical nightmares when it comes to explaining how they work. Apparently, the way the Japanese "Dragon" Cards work is that any character who picks them up immediately gains a fusion deck about two feet deep to represent every possible fusion combo that the Dragon in question may form.
 * The rules of the Death Note say that you can't use it to cause murders; in the Live Action Adaptation, Light gets around this by setting up two deaths so that the only possible way they could occur is if Person A kills Person B. Ryuk is so impressed, he tells Light that he'd make a better Shinigami than any of the ones he knows.
 * If you want to know the specifics, he wrote and . He also points out that Japanese gun control laws (that is, civilians are not allowed to own them) make it extremely unlikely that any other guns would be around to mess this up.
 * Both Leonard Apollo and Himura Youichi in Eyeshield 21 used loopholes to get out of their obligations and back into their respective countries. Apollo stated that if they failed to beat the Devilbats by at least 10 points, the NASA Aliens would never return to America. When they failed to meet that goal, Apollo revealed that he was just going to change the team's name to the NASA Shuttles; That way, it technically wouldn't be the NASA Aliens going back. Likewise Hiruma said that if the Devil Bats didn't beat the Aliens by at least 10 points the entire team would leave Japan. However he never said they would leave Japan forever...
 * Saitama Chainsaw Girl has protagonist Fumio observing that there's no rule against bringing a chainsaw to school, after the student council president tells her off for not switching to her school shoes. This being while Fumio is holding a bloody chainsaw.
 * Rocket Girls: Ain't no rule that says you can't send a high school girl into space!
 * In Urusei Yatsura, Mendō says that, although motorcycles aren't allowed at school, there's no rule against helicopters.
 * Invoked but averted in chapter 42 of the manga version of Shinryaku! Ika Musume. During a soccer match where Ika is performing poorly, her teammates realize the rules only say non-goalkeeper players can't use hands to move the ball. There's not a thing in the rules about tentacles (especially since Ika's tentacles are technically part of her head, which explicitly can be used to move the ball). But since Ika's trying really hard to play the normal way, they don't mention this loophole to avoid hurting her pride.
 * G Gundam has quite a few instances of nations finding loopholes in the rules. One of the most famous is the Nether Gundam; the rules say that any Gundam that goes through the Survival 11 without losing its head makes it to the finals. Neo Holland's Gundam turned into a windmill, spent the 11 months hiding without participating in a single fight, and qualified (didn't do very well afterwards though). Then there's Neo Nepal: the rules say that you can't kill your opponent during a Gundam Fight, but there Ain't No Rule that keeps you from going around assassinating your opponents right before your match...
 * In Beelzebub, when Oga is asked whether or not he's going to play volleyball with a baby clinging to his back, everybody agrees something to the effect that it's okay since the baby is a part of him. Later in the match, the Ishiyama team hilariously use Baby Beel to distract/trick the other team.
 * At least in Bokurano's anime, it's played straight twice in a row when Kokopelli asked Koyemshi to let him fight the last battle on their Earth and the demo battle on the next Earth so his also contracted daughter Yuu wouldn't have to fight. When Koyemshi stated it was impossible, Machi stated he could do just that because there is no rule that prevents you from becoming the pilot for more than one battle. Koyemshi retaliated: the rules are specific enough to state that you're still bound to the contract and keep being the pilot if you survive the battle without moving . Kokopelli moved, so he technically doesn't have to be the pilot for the next battle. No points for guessing who was the one selected as the final pilot.
 * In Darker Than Black, only the Contractor's original body is obliged to fulfill their Renumeration which, obviously, doesn't have to be fulfilled if said body dies. Thus, there are two sorts of Contractors who can effectively obtain free use of their powers: Contractors with Grand Theft Me powers that lost their original bodies (such as Mao), or Contractors whose powers aren't actually their own (such as ).
 * For the most part, angels only officiate the Queens Blade competition. However, there are no rules against angels entering it - which Nanael discovers, to her dismay, when the head angel makes her enter (because Queen Aldra is not someone you want in charge for longer than you have to).
 * Sora no Otoshimono has Angeloids, All-Powerful Robot Angel Genies which programmed to do anything that their master tells them to, with the caveat that they cannot cancel an order once it has been given. That doesn't stop them from forgetting that their master gave a specific order, or making it so that whatever went wrong was All Just a Dream.
 * Done by virtually every team other than Team Urameshi during the Dark Tournament arc of Yu Yu Hakusho.
 * Digimon Xros Wars the Young Hunters Leaping Through Time has an excellent example of this in one episode. A powerful Digimon is blocking all of our heroes' attacks with a seemingly impenetrable barrier. It's suggested that they bring out Shoutmon X4, the signature Digimon of the previous season, but the problem is that, in the current situation, the humans are forbidden from combining more than two Digimon at once, and cannot have more than one present and fighting at a given time. Since X4 is a combination of four Digimon, it would seem impossible to bring him out- but Taiki figures out how to circumvent this. He temporarily lends two of X4's components to teammate Yuu, then they perform the Double Xros maneuever, each using two Digimon, which enables them to successfully Xros Shoutmon X4.
 * Inverted, then played straight in Rinne no Lagrange: There's no rule saying that a student may pilot a Humongous Mecha... nor is there a rule saying they may not do so.
 * Ai no Kusabi has ruling Blondie Iason Mink making Badass Biker Riki his Pet. Something that just isn't done since Riki is a "mongrel", disenfranchised with no hope of climbing the social ladder and owning Pets indicate one's social status. Iason claims he doesn't have to follow the protocols for owning a Pet with Riki because he's a mongrel, has no official identity and thus the rules don't apply to him.
 * The latest arc of manga Katekyo Hitman Reborn is a battle royal with one set of rule that really straightforward and simple it's a wonder why no team tried to exploit for seventeen chapters.  exploit the loophole   and
 * In Eyeshield 21, after seeing an insulting viral video that embarrasses the NASA Aliens coach Apollo, he furiously declares that if the team doesn't win more than 10 points in the game against Deimon, the NASA Aliens would never go back to America. Despite winning the game, it was less than a 10-point difference. So Apollo declares that he's renaming the team to the NASA Shuttles so the NASA Aliens won't be returning.
 * Hiruma does the same thing. In challenge of Apollo's statement, he said that if the Devilbats doesn't win by more than 10 points, the entire team will leave Japan. However, he never said they would not be coming back.