Forbidden Chekhov's Gun

[beginning of the movie]
K: Whoa there! Don't push that. Never, ever push the little red button.
[end of the movie]
K: Remember the little red button? Push the little red button. And you may want to put on a seatbelt.

— Men in Black

Remember the Chekhov's Gun that was on top of the mantel? The one Little Bobby was told never to touch, under any circumstances? Now's the time to grab it. This is a specific subtrope of the Chekhov's Gun where someone points out the "gun" and explicitly warns against using it. It doesn't have to be a Matter of Life and Death. It can be as simple as being told not to push a button, then later being told to push it.

Subtrope of Inevitably Broken Rule. Often used in conjunction with a Godzilla Threshold. Compare Dangerous Forbidden Technique. Mildly related to Explosive Overclocking, Temporal Paradox, and Finishing Move.

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Examples:

Anime & Manga

• In Castle in the Sky, Sheeta mentions to Pazu that her pendant has a spell of destruction that her grandmother taught her, but told her never to use. Guess what they end up using at the end of the film?
• Avan from Dragon Quest: The Adventure of Dai developed Grand Cross as a Godzilla Threshold skill. He specifically states that it's only intended to be used when everything else has been tried, which warns the viewer this skill will only be used at a story climax.
• EDENS ZERO: A Running Gag in the story is Mosco having a button on his belly that Sister frequently yells at him not to push. However, in the Universe Zero arc, when he, Sister, and Pino are paralyzed by Clown, Mosco tells Happy to press the button to save them. This turns Mosco into Cosmo, a powerful and handsome butler that dispels the gas and makes it easier to defeat Clown. The real reason that pushing the button is forbidden? Cosmo is capable of making Sister into his submissive bondage slave.
• Slayers offers another example with the Giga Slave. In order to keep it from being Lina's answer to every problem, a Godzilla Threshold aspect was introduced. Lina learns that the spell could cause the world to turn to chaos, and vows to never use it again; naturally, she's forced to do so at the end of Slayers Next.
  • It's not always used when there's a climax. The end of season 1, like the end of NEXT, is one big attempt to get her to perform the spell. She doesn't. Almost the entirety of Try, once the characters learn who the Big Bad is, is about finding a way NOT to use it. They succeed, but Lina always accepted that she may have to use the Giga Slave if their plan didn't work.
• Sugata of Star Driver has access to an extremely powerful first phase ability, the King's Pillar. However, every previous bearer of Samehk's mark who used the ability never woke up again. The time comes when he has to protect Wako, and well, you can guess what happened. Luckily for Sugata, his libido was strong enough overcome that effect.
• Madoka in Puella Magi Madoka Magica is essentially a Forbidden Chekhov's Gunman. Kyubey repeatedly states that she'd have incredible, godlike power if she made a contract, but the other girls—especially Homura—keep preventing her from going through with it to spare her from a magical girl's life of tragedy. Eventually, it becomes clear that her transformation would probably cause The End of the World as We Know It, because every magical girl inevitably becomes a witch if she lives long enough, and the most powerful magical girl would become the witch to end all witches. Homura knows this will happen; being a time-traveller, she's seen it firsthand (and is the major cause because the nature of her time-traveling actually makes Madoka's potential (and thus her Witch) even stronger with each loop). But Madoka eventually makes a contract in a way that avoids this inescapable downside at the cost of her needing to Ascend to a Higher Plane of Existence.
• Naruto features the concept of the Eight Gates in the body that regulate a person's chakra flow. These gates can be opened and with each opened gate, the user of this technique becomes stronger and faster. This process greatly damages the body, however, and if the Eighth Gate is opened, the user will die. After years of Might Guy and Rock Lee gradually pushing this technique further, we get to see the Eighth Gate in action exactly once during the finale arc. Guy uses it to (temporarily) become stronger than a Ten Tails-powered Madara Uchiha, and is only saved from death by Naruto.
• Plan Z was first brought up in chapter 44 of Green Worldz but never revealed its purpose, only that it should only be used as a last resort. It was later used by Iwatobi to restore his original fighting capabilities at the expense of his life as it heavily burdens his heart.

Comic Books

• In The Flash storyline "Terminal Velocity", Wally has various reasons to believe that pushing his superspeed too far is a Godzilla Threshold that will draw him into the Speed Force, never to return. He tries to avert a conflict which he knows will force him to do this, but to no avail. However, when he does finally enter the Speed Force, he manages to return (which no one has done before) thanks to The Power of Love.
• In the Asterix comic series, Getafix does not allow Obelix to drink the magic potion, as he fell into the cauldron as a boy, and an extra helping could have bad effects on him. But in one story, Asterix and Cleopatra (both the comic book and the animated version), Getafix gives him just a drop of potion to give him extra strength in a difficult situation. Also overlaps with Godzilla Threshold. It's justified: a later book shows that if Obelix drinks a large amount of potion, he'll be turned to granite.
• Fone Bone, Gran'ma Ben, and one of the Dreaming Masters were the only people who didn't want to do it, but near the end of Bone, the Crown of Horns seems to be the only way out, even though it's been said that if Thorn even touches it, all of existence would be in jeopardy, and the trip there would be dangerous anyway with all the dragons that guard the Crown of Horns and intend to kill anyone who's anywhere near it. Fone Bone improves their chances by not actually touching it, just grabbing Thorn's hand and almost touching it via static shock.
• At the beginning of the Supergirl arc Red Daughter of Krypton, the Red Lanterns explain to Supergirl that she can never, ever, take her Red Lantern Ring off since she would die. At the end of the story, Kara removes her ring to try to kill an enemy that was taking over her body. She ends up surviving after being thrown into the sun, which amplifies her Healing Factor enough to grow her a new heart..

Fan Works

• Chiaroscuro: Shikaku's "original" Shadow-splitting technique wasn't just a random power-up. It was actually a rediscovered version of Kaguya's Will Manifestation technique.
• Harry Potter and the Rune Stone Path: Bathsheda Babbling tells Harry to never ever even try to attempt an Animagus ritual which was made illegal due to the danger of dying or being stuck in your animal form forever. Guess what he ends up using to help him escape from a chimera in a souped-up version of the Triwizard Tournament...
• The Moment in the Doctor Who fanfic The Last Great Time War.
• A Very Potter Musical: Played for Laughs when Harry shouts: "don't cross the streams!" when the trio summon their Patronus. And Malfoy. But the dialogue the Ghostbusters use is used in AVPM as well, though to dicuss why Harry has to compete in the House Cup tournament rather than beam-crossing.

Films — Animation

• In Over the Hedge, characters tell Hammy not to drink caffeine, it could be dangerous to him, as he's already hyperactive. Later, they tell him to drink caffeine to cause more hyperactivity.
• My Little Pony: Equestria Girls – Legend of Everfree: Timber Spruce mentions from the get-go that the abandoned rock quarry is off-limits. Although it's perfectly logical for such a place to be considered dangerous, it naturally proves later to have a very important place in the plot.

Films — Live-Action

• About a third of the way into Fantastic Four (2005) when the Four are running tests on their capabilities, Johnny gets so hot he melts the walls of the test chamber. Reed stops the test with fire retardant foam, then explains to him that he'd gotten almost as hot as a supernova and that this was bad. During the fight with Dr. Doom at the climax, Reed tells Johnny to go supernova inside Sue's forcefield to try and melt Doom. Johnny lampshades this with a concerned "I thought we agreed that was bad!"
• The Omega 13 from Galaxy Quest. Somewhat played with. None of the characters even know what it does, including the aliens who built it. So they don't want to use it, because they don't know what it will do, and it has a potential energy output capable of annihilating the universe. This is because it was only mentioned before the cliff-hanger ending of the two-part episode that was never finished when the show was canceled. They eventually gamble on a fan's theory that it rewinds time by 13 seconds, which turns out to be correct.
• Ghostbusters has the iconic warning "Don't cross the streams," which they inevitably have to do at the end of the movie. As former Trope Namer, it was also causing confusion, since this overlaps with Godzilla Threshold. In this case, the non-disaster when they do end up crossing the streams makes internal sense: they are firing into a Parallel Universe Eldritch Location where a dark god trying to destroy the world is based, and presumably, the disaster that Egon predicts happens there— and closes the gate.
  • In the 2016 remake, Jillian tells the gang not to shoot the Ecto-1 after Slimer steals it in case the reactor explodes. They end up doing this on purpose at the end to Reverse the Polarity of the Hell Gate to make it suck all the ghosts back in.
• The Gunstar's Death Blossom attack in The Last Starfighter; not so much that's it's insanely overpowered (although it is), as that it's never been tested before and might possibly blow up their ship.
• In the Lost in Space film, ships have hyperspace engines, but it is not a good idea to jump without coordinates or a jump gate, as the exit vector would be random. The crew does this anyway when the ship is sabotaged and crashing into the sun. And again at the end of the film when the planet that they crash-land on turns into a black hole; it's not revealed where they end up.
• Agent J in Men in Black is told by Agent K to never, ever touch the red button inside their car. When the two need to get across the city in a hurry and the tunnel is jammed, he is at last told to push the button— transforming the car into a high-speed rocket that drives along the ceiling of the tunnel.
• Men in Black II: Jay uses "Pressed the Red Button" as a type of code, indicating that it is reserved only for the biggest emergencies. They seem to prefer to not even use the neuralyzer if they don't have to, so going for a rocket car ride would likely be a last ditch number on their list of priorities.
• In Orgazmo, Choda Boy swears off using his dangerous "Hamster Style" at a young age due to its unpredictability, but at the movie's (heh, heh) climax, he employs it with great results.
• Marvel Cinematic Universe:
  • In The Avengers, the whole team (minus Tony) spends a lot of time trying to keep Bruce Banner calm. Then the alien invasion arrives.
    [alien leviathan starts heading towards the group]
    Captain America: Dr. Banner! Now might be a good time to get angry.
    Banner: That's my secret, Captain. I'm always angry.
    [Banner Hulks Out and punches the leviathan]
  • During the Training Montage in Ant-Man, Hank warns Scott not to tamper with the shrink suit's regulator. Doing so would risk Scott going subatomic and effectively disappearing. Scott eventually does so as an intended Heroic Sacrifice to slip past Yellow Jacket's titanium plating to destroy his suit.
• The Fast and the Furious (2001): The Dodge Charger in Dom's garage belonged to his father, and nobody, not even Dom, dares drive it... until the last ten minutes of the film.
• Early in the Australian lawn bowls comedy (uh huh) Crackerjack, Jack tries a "flipper" - in short, a cricket thing transposed to lawn bowls - with disastrous results. He's angrily told never to pull that crap again, but when he has to pull off an almost impossible shot in order to win the championship, he's explicitly instructed to do it.
• In The Rundown, Beck refuses to use guns because "bad things happen" when he does. In the final showdown, he realises that he has no choice, and bad things do happen... to countless mooks.

Literature

• The Door to Nowhere and Nowhen serves this function in The Redemption of Althalus.
• Discworld:
  • In The Colour of Magic, one of the eight spells from the Octavo (eight is an important number on the Disc) has lodged itself in Rincewind's mind. He doesn't know exactly what it does, but popular wizarding opinion is that it will destroy the Disc (especially if cast alone). As a semi-sentient entity, it tries to cast itself. Rincewind barely prevents himself from casting it several times through the course of the first two books (which is one story) The Colour of Magic and The Light Fantastic. When he does lose control, a significant event is already happening and the seven other spells have been cast. At this point, it's not a spell to destroy the world... but to create others.
  • In the back-story of Going Postal, an automatic letter-sorting device with extradimensional components (it accesses a dimension where pi is exactly equal to 3) goes out of control, filling the Ankh-Morpork Post Office with letters. Wizards called in to inspect the device warn that shutting it down is likely to destroy the universe. Fed up with the machine, a veteran mail-carrier starts smacking the device with a crowbar until it shuts down. When the mail-carrier started hitting the device, the wizards ran away. As the doer of the deed testified, unless they had some other universe to run to, they weren't really sure about the danger. The wizards insist that the universe really was destroyed, but was instantaneously replaced by a complete, identical universe. That exact thing has actually happened before in that series. Twice, depending on how you count.
    • An unusual example, in that this was a ending-the-universe danger, but never actually crossed the Godzilla Threshold before it was destroyed.
• As per Word Of Jim, Harry Dresden will eventually break all seven Laws Of Magic.
  • Harry broke the First Law of Magic when he was a teenager prior to the series start, which is the cause of his antagonistic relationship with the White Council as they were going to execute him for killing in self defense. In Grave Peril Harry realizes it's possible he broke the First Law when he used magic to burn down Bianca's mansion as there were possibly humans killed in the blaze. If this is found to be true the council will hand him a death sentence for it.
  • Dead Beat: Harry broke the Fifth Law of Magic when he reanimated Sue. His necromancy falls into a loophole and he is not prosecuted for it by the council since he did not use it on a human but it colors the council's opinion of him going forward.
• The Chronicles of Thomas Covenant (at least the second one), after spending the last two series trying to prevent Lord Foul from obtaining Covenant's white gold ring in the final confrontation Covenant just hands him the ring. It turns out to be a massive Batman Gambit, as Covenant had finally come to understand how the white gold worked, and was able to trick Foul into destroying himself with the power.
• Thursday Next has a switch located behind a pane of glass to break in event of "unprecedented emergency" — with the explicit note that "personal destruction" is not an unprecedented emergency. Unusually for this trope, the glass is not broken by the end of the book - but it is broken in the next book.
• In Marion G. Harmon's Wearing the Cape, Astra specifically uses one maneuver Atlas had carefully warned her against, even thinking at the time of his warning that an attack like a missile — well, you never reuse missiles.

Live-Action TV

• In Babylon 5, the "Bonehead Maneuver" as mentioned in the Season 3 premiere. You have two ways of going in and out of hyperspace. If your ship is powerful enough, you can open your own jump point, or, if your ship isn't that powerful, you have a Jump Gate open one for you. You never want to open a jump point inside a jump gate, because this causes one massive explosion of a Negative Space Wedgie. Aside from the loss of a very hard to replace jump gate (typically a star system will have one at most) and potentially stranding people in the system if they lack massive starships, this doesn't actually cause any huge universe-altering affects. Just a huge explosion that is impossible for most ships big enough to open a jump point to outrun (so not really a Godzilla Threshold). They end up using the trick in a tricked-out new spaceship that MIGHT be fast enough to get away after using this trick to kill an enemy they DEFINITELY weren't big enough to fight. Also? Considering the amount of damage the enemy would do...going out killing it is a pretty good idea?
• In Better Call Saul, the second season premiere is titled "Switch." This refers to a switch Jimmy sees in his office with a taped sign that reads "Do NOT turn OFF!" At the end of the episode, he peels back the tape and switches it. Nothing happens. He switches it back and puts the tape back on.

Radio

• In The Hitchhiker's Guide to the Galaxy (1978), it's generally a really bad idea to activate the Infinite Improbability Drive on the starship Heart of Gold without proper programming, as anything could happen as a result. However, when confronted with imminent destruction by a pair of nuclear missiles, Arthur Dent goes ahead and does it anyway, since almost anything else would be an improvement. Luckily, the only thing that happens this time is a redecorating of the ship's bridge, and the two nuclear missiles being replaced by a live sperm whale and a bowl of petunias. (Also occurs in the book, TV series and movie adaptations.)
  • If we knew why the bowl of petunias thought "Not again!" while falling, we would probably understand a lot more about the universe. Later in the series, we find out EXACTLY why; it's one form of someone whose every incarnation keeps getting killed by Dent. It Makes Sense in Context.
  • Averted in the case of the button which, when Arthur pushes it, brings up a message that says "please do not push this button again". He doesn't push it again.

Tabletop Games

• Warhammer 40,000 gives us the Spear of Twilight, which will doom whoever removes it from stasis to death from a wasting curse. Prince Yriel saved his Craftworld from being eaten by Tyranids by using it.
• This is a commonly used tactic in Fiasco playsets, as usually the goal of the game is to create as atrocious a mess for the characters as you possibly can, so Objects (and, to a lesser extent, Needs and Relationships) with built-in bad ideas pretty much guarantees they'll be the centre of the action. A good example is one Object in "White Hole" - "Stasis gun. (Do not fire the stasis gun.)"

Theme Parks

• At Universal Studios:
  • During the pre-show of Hagrid's Magical Creatures Motorbike Adventure, Arthur Weasley warns Hagrid that the "dragon's fire" speed boost is to be used on the motorbikes only in the event of an emergency. Towards the end of the ride, Hagrid activates it as a means of getting the riders away from a bunch of Blast-Ended Skrewts.
  • In the Men in Black: Alien Attack ride, a Big Red Button appears in every ride car. Like in the film, you are told never to press it. However, by the end of the ride you face a giant alien that's immune to your weapons. Guess what you have to do? A cheesy instruction video seen while in line on the ride explains exactly WHY you don't press the button; it's a nuke capable of frying the more Kaiju-esque aliens.

Video Games

• At the beginning of Borderlands 2, Claptrap tells you of a gun he keeps in his cabinet, but "only for emergencies." There's an emergency.
• Press X to Die is a video-games-specific instance of this, in which the game will really be over if the player actually fire the forbidden gun. Usually, the gun is some kind of weapon of mass destruction.
• In the Shadow Hearts series all characters have a Sanity Meter. If it depletes completely, the character goes berserk, attacks their allies, and will not gain experience when you win the battle. The strategy in many difficult battles involves keeping this stat up while various effects suck it away. How does one unleash the final, most powerful attacks of the main character in the first game? By leveling his transformations up to max and then going insane while fighting in them. Something of a Guide Dang It!.
• In the Ultima series, the Armageddon spell (which kills everything and destroys the entire world when cast) has always just been used as a Red Herring to give the player a Non-Standard Game Over, but by sealing oneself inside the separate universe made by a Barrier of Life spell with the Big Bad in Ultima IX: Ascension, the player is able to destroy just the universe he's in right now, along with his opponent and himself.
• The first Halo trilogy had you trying to prevent the Halos from going off. Guess what the last level of Halo 3 has you doing? It was only one Halo, not the whole set, but the concept remains the same. Cortana even handwaves it. The reason for trying to prevent that is that the Halos are meant to kill all life in the galaxy. The one in the third game is outside the galaxy as noted in the first level on the Ark. One marine points out that the Milky Way is visible in the sky, meaning you're not in it.
• In Breath of Fire: Dragon Quarter, Ryu must unleash D-Breath against Chetyre in the true final battle until the D-Counter hits 100% to trigger the final scene - an action that earns a Nonstandard Game Over everywhere else.
• In Destroy All Humans! 2, this trope is played for laughs in one of the final missions. In order to stop the superweapon going off, Crypto must cross the beams of a targeting system. The entire Ghostbusters conversation is used verbatim on why this would be a bad idea.
• In South Park: The Stick of Truth, the "Gentleman's Code" warns that you should never fart on another man's balls. You are given this warning every time you learn a new Fartillery power. Of course, you are forced to fart on Zombie Nazi Princess Kenny's balls in order to defeat him.
• In Castlevania: Order of Ecclesia, using the Dominus Anger, Dominus Hatred, and Dominus Agony glyph union kills Shanoa instantly. Guess what you have to do to beat the final boss? Though, as a result of a Heroic Sacrifice, Shanoa survives. Turns out that the glyph consumes a soul, not necessarily the user's. It just so happens that Albus was forced to hang around after his defeat and was able to take Shanoa's place. This is in the Good End. The Bad End has Shanoa die after using the glyph.
• Fate/stay night. Specifically, using Excalibur, the first Deus Sex Machina (maybe), Shirou's arm, taking on Caster/Kuzuki directly on their turf (not a dangerous technique but the strategy is essentially suicide) and projection in general.
• Tsukihime. Shiki, you've got about thirty seconds before Roa takes over your mind? What are you going to do now?' Answer: Stab himself in his own point of death on the assumption that if his will is stronger than Roa's, he'll live through it and Roa will die instead. Still, it's not like Ciel had any other ideas, and Arcueid provided backup by way of a single drop of her blood. (Thus sharing her will with his and allowing him to overpower Roa with relative ease.)
• Magicka lets you do this with the Arcane element and other elements to alter the beam's qualities, resulting in a combined, powerful beam. But if beams of opposing elements cross, a huge explosion occurs that will likely kill anyone nearby. Players may exploit this when fighting goblin shamans and other enemies that use beam attacks, intentionally or accidentally.
• In Final Fantasy VIII, Ultimecia's end goal is to compress time. Because she exists generations into their future, the heroes end up having to allow her to begin time compression so that they can get to her to prevent her from compressing time.
• Happens again in Ghostbusters: The Video Game, except this time due to being in the ghost world - where the same rules of physics don't apply, such as the lack of gravity on the actual landmass - one can probably assume that you can cross the streams without frying your ass to bits because the chances are reversed, thus making it more safe to try.
• The Great Clock's purpose in Ratchet & Clank Future: A Crack in Time is specifically stated several times throughout the game to be maintaining time, not reversing it. Time-travelling with it would cause the entire universe to collapse on itself. Naturally, Clank has to use it to turn back time by only a couple of minutes at the end of the game after Azimuth kills Ratchet.
• The command that stops the Big Bad from sacrificing you to end the world in Trilby's Notes is DIE. Yeah.
• Metroid: Other M combines this with A Taste of Power for the Power Bombs. You test them out in the beginning of the game, and are promptly told to never use them, and in fact attempting do so will fail. Until the final boss, where you HAVE to use them after being swallowed. Also a Guide Dang It! since you have, most likely, completely forgotten they exist by that point and wouldn't think to use them after all the hubbub about not using them previously.
• RuneScape: Downplayed in the Rune Mysteries quest. You're warned not to play the lower registers on the giant organ because it'll make a loud noise and annoy everyone in the tower. Later, at the end of the quest, you need to bang on the keys to create a distraction.
• The Lemmings series has the Nuke button, which can be used for a mass mercy killing if you screw up the level, or to sacrifice extra lemmings once you rescue the required amount.
  • And in at least one case it's needed to finish a level.
• Super Robot Wars UX: The Orphes' Lepton Vector Engine which is a portable "Particle Acceleration Reactor". Basically what it can do is bypass space and time but the problem is that it damages human organs through continuous use. Think of it kinda like a semi-time machine but the pilot's getting microwaved.
• La-Mulana 2 warns the player repeatedly that invoking all of the Mantras simultaneously will result in death. Sure enough, doing so results in Lumisa instantly dying. Much, much later, reciting all of the Mantras simultaneously is required to awaken the Final Boss.
• The Evil Ring in Ys: Ancient Ys Vanished ~ Omen normally kills you if you equip it. However, you later need to use it in combination with the Blue Necklace to access the area where Lair is imprisoned.
• In Bureaucracy, your character's blood pressure rises each time you attempt to do something that you cannot, like open a locked door without the proper key. If your blood pressure gets too high, you suffer an aneurysm, and it's game over. Late in the game, you are required to get your blood pressure up to fatal levels in order to open a door by sheer brute strength.
• In The Legend of Zelda: Tears of the Kingdom, Mineru speaks to Zelda of the forbidden ritual of draconification - how swallowing a secret stone turns the imbiber into an immortal dragon, albeit a mindless one; this side effect to the mind is the reason why the ritual is forbidden in the first place. Zelda, who was trying to find a way to return to her time, dismisses the notion out of hand, as losing her mind would mean she would not recognize anyone in her time, even Link. Later, after Mineru's body is destroyed and Rauru sacrifices his to seal Ganondorf away - after Ganondorf stole Sonia's secret stone to become the Demon King, at that - Zelda receives the Master Sword from the future and realizes that, given her power over sacred light, all she can do for Link is repair the Master Sword until it returns to his hands. And thus, to carry out that deed, she swallows the secret stone in her possession.

Webcomics

• This is the same way 8-Bit Theater character Red Mage's Ice-9 spell (a reference to the novel Cat's Cradle) works: as the description puts it, it removes all heat from the universe it is used in, thus destroying all energy. He can only use it on other dimensions, like a bag of holding that he shoved an enemy in... which White Mage then smashes with a hammer.
• Bob and George's ultimate team-up attack is named as such, and is described by Bob that it'll definitely kill Mind, but might kill him, George and Dr. Light in the process. They decide to attack anyway. Bob and George first shoot streams of fire and lightning energy at Mynd, then Bob channels his fire into George, the end result being exponentially more powerful than the two alone.
• In The Inexplicable Adventures of Bob, from the moment Galatea learns about the insanely dangerous forbidden Nemesite super weapon, the "Butterfly of Iron," it's pretty much inevitable that she's going to find and activate it. When she does find it, she hesitates for a moment until her companion tells her from offscreen, "It is forbidden!" She shoots him a dirty look and pokes the button out of spite. Hilarity Ensues.

Web Original

• SCP Foundation has combining the two major Nothing Is Scarier SCPS: SCP-055 (the one where you can only remember what it isn't) and SCP-579 (the one whose entire page is redacted). Their effects on each other are only ever described as "can't fit round pegs in square holes", but it's been used twice; once when aliens conquered Earth and once when the Foundation tried to destroy humanity. In both cases it acted as a Reset Button.

Web Video

• In the first episode of Adventures in Jedi School, Master Mudmud emphasizes how dangerous lightsabers can be, with poorly-built lightsabers capable of exploding. In the second episode, Randy shows off his own personally made "rush-job" lightsaber, which of course explodes and eviscerates him on the spot.

Western Animation

• Johnny Test: Johnny teams up with some villains to save the Earth, and they're told right before they head out to not use their powers while holding hands, since it could multiply their powers by 500% or something. Naturally, when their plans are thwarted, they turn to this. It sounded like the villains refused to do this, and Johnny teamed up with his... dog.
  • The dog can talk, and they always team up.
    • They did this gag before. "We have to cross the creams!"
• The Real Ghostbusters:
  • In one episode the Ghostbusters were falling toward a body of water from high enough to kill them on impact. Egon's solution? Have them fire at the water and cross the streams; the resulting explosion kicks up a huge column of water which breaks their fall enough for them to land safely. Upon landing safely, one of them asks how Egon knew it would have that effect. Egon's response? He didn't; he just thought it might help. We are talking about a guy who engaged in this exchange in the film:
    Peter: Egon, this reminds me of the time you tried to drill a hole in your head.
    Egon: That would have worked if you hadn't stopped me.
  • In "The Boogeyman Cometh", Ray claims that using the Proton Beams at all in the Boogeyman's in-between dimension could be even worse than crossing the streams. (And this time, they don't try it; their plan is far-more thought out.)
• In Transformers: Prime the Autobots have the Spark Extractor in their inventory, they won't use it unless they really need to hit the Decepticons hard. They use it when they are fighting them on Cybertron.
• In the classic Looney Tunes short "Design for Leaving," Elmer's house gets rebuilt with all kinds of futuristic gadgets (which don't work right, naturally). Among them is "this wed one, wight here," to which Daffy the salesman responds, "No no no no! Not the wed one! Don't ever push the wed one!" It's to escape tidal waves. It elevates the house hundreds of feet up into the air. When Elmer pushes it at the end, Daffy comes by in a helicopter to let him know that "For a small price, I can install this little blue button to get you down."
• During the beginning of one episode of Batman Beyond, when Terry asked why Bruce never got to use an experimental, heavily-armored type of Batsuit in the Batcave, Bruce told him that it put a massive strain on his heart condition. Later in the episode, Terry gets kidnapped by Inque to lure Bruce into a trap. Bruce waltzes right in, and just when Inque believes she's strangling him Bruce breaks out of her grasp and reveals that he was now wearing the armored suit. At the sight of this Terry has an Oh, Crap!, and indeed during the fight operating the suit is taking its toll on the older Batman.

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