Hoist by His Own Petard/Literature

"Harry: "I must not tell lies." STUPEFY!"
 * Two examples from The Hunger Games:
 * Coin gives Katniss the bow and arrow to execute Snow with. Guess who she ends up shooting.
 * Snow would constantly drink a poison to build up his resistance so that he could poison his political opponents. After he was deposed, it's strongly suggested that he was dying partly from the effects of the poison catching up to him (although it didn't have time to kill him before he was trampled to death...)
 * The term is actually used in The Green Mile to describe how by trying to plead innocence, Percy Wetmore ends up looking extremely incompetent.
 * In A Series of Unfortunate Events, Count Olaf is killed by the same harpoon gun he packed planning to release the biological weapon on the island. This is after being nearly poisoned by that same biological weapon.
 * In A Tale of Two Cities, most of the revolutionaries, including Ernest Defarge, Barsad, and the Vengeance, are eventually executed by their own guillotine.
 * Used in Jurassic Park. The monsters where created for a theme park rather than as weapons but the trope is still followed.
 * In Thanks To The Saint's final story, "The Careful Terrorist", Simon Templar is opposed by a gangster, and his professional hitman, nicknamed "The Engineer", and manages to make him blow himself and his employer up. Then he quotes the Trope Namer.
 * Harry Potter
 * In Harry Potter, Voldemort is finally defeated when his own Avada Kedavra is reflected back in his face by an Expelliarmus from Harry. Arguably, the first time Voldemort tried to kill Harry, only to have it backfire and blow up in his face, counts too - even though he didn't stay dead.
 * Something similar occurs in Harry Potter when Lockhart's memory charm backfires on him, because he was using Ron's very broken wand to cast it. Dumbledore mocks this ("Impaled on your own sword, Gilderoy?").
 * Non-fatal example: In OotP, we see a memory of Harry's dad picking on Snape by making him hang upside-down in midair. In the next book, Harry finds the potions book of the guy who invented that spell...and at the end of the book, it turns out to be Snape himself.
 * In Deathly Hallows Crabbe tries to kill the main trio with Fiendfyre. Since he lacked the skill to actually control Fiendfyre, the cursed flames consumed their summoner.
 * Tom Riddle Sr., upon finding out that his pregnant wife was a witch and had used magic for making him fall in love with and marry her, abandoned her and her unborn child and purposefully never bothered to find out what happened to either of them. Said child grows up to become Voldemort, learns the truth, and decides to kill Tom Riddle, Sr. in revenge for his having been abandoned by him and left to be raised in an orphanage.
 * Umbridge really shouldn't have gotten onto Harry for even perceived lying. He actually weaponized his detentions under her at least twice later on. The second time basically ended up like this:


 * A minor one in Half-Blood Prince, Horace Slughorn contains a memory that is crucial to Harry knowing how to defeat Voldemort. However, he is ashamed of what he told Voldemort in the memory, so he resolves never to show it to anyone, and keeps several means of fighting off people who come for the memory on his person at all times. However, at the beginning of the year, he gave a bottle of Felix Felicis (Liquid Luck) to the person who made the best Draught of Living Death on their first day. Harry made the best Draught of Living Death potion, and later that year, was able to coax the memory out of Slughorn under the influence of the exact same potion Slughorn gave Harry during their first lesson.
 * In a supplementary material to Guardians of ga Hoole, a Tropical Screech Owl named Honeyvox drinks the potion meant for his enemy, muting him for life.
 * In Dan Abnett's Warhammer 40000: Gaunts Ghosts novel First & Only, Rawne is kidnapped and tortured by Heldane before Corbec and other Ghosts rescue him. He intended to make him a "pawn" but succeeded in only making him sensitive to influence. This, however, let Rawne sense when Heldane was about to unleash his actual pawn, and bring his weapon to bear beforehand.
 * In a kind of play on this trope, in the first of the newest Wild Cards novels, "Inside Straight", African American Ace Stuntman manages to win a challenge on the reality show he is participating in by accusing one of his opponents of using a racial slur against him. In the next novel, "Busted Flush" Stuntman main role in the storyline is fighting a genuine racist (while the guy who he accused of being a racist went on to be part of the UN super team).
 * In Graham McNeill's Warhammer 40000 Ultramarines novel Dead Sky Black Sun, Honsou has Uriel killed by putting him into the daemonculaba. He breaks free. Since this was the process by which the Unfleshed were created, they smell it on him, and are willing to listen to him; he gets them to join him on an attack on Honsou's fortress.
 * In Logos Run, an evil circus master tries to kill the heroes with his dangerous poisonous snake. Once introduced to a scent, it will unerringly kill that person. His comrades all wondered why the snake had never bitten him. After sending the snake, he is injured in an unrelated event. The intended victim actually helped him by bandaging him. When he woke up, the first thing he asked was who put the bandages on him. The snake struck right after he got the answer...
 * In James Swallow's Warhammer 40000 novel Deus Sanguinius, Inquisitor Stele summons a daemon to a battlefield. It choses him as its flesh vessel.
 * In A Song of Ice and Fire, the loathsome city of Astapor brutally trains eunuch slave Super Soldiers for sale as mercenaries as well as to defend the city. Astapor has nothing to fear from its own soldiers, who are robotically loyal and cannot disobey an order from their masters. However, no one thought it was a bad idea to sell every single soldier they have to an ambitious warrior queen, thus turning their entire garrison into a foreign army that's already inside their walls.
 * Then there's Cersei's brilliant actions as Queen Regent: she reinstates the Church Militant wing of the Faith of the Seven in order to pacify the rioting faithful, while plotting to expose frame the betrothed of her son (the crowned king) as engaged in an extramarital affair. However, the guy she sends to seduce and spill on her son's fiancée ends up tortured by the new High Septon, and confesses that he's had relations with Cersei as well. She ends up in the cells rather quickly.
 * Hell, the very first book has Ned Stark, whose plans to expose Cersei's adultery and Joffrey's illegitimacy end with him playing straight into the Lannisters' hands.
 * In Atlas Shrugged, Robert Stadler tries to take over a Death Ray installation that he feels belongs to him. The outcome of the struggle is the obliteration of him, the building, and everything within a 100-mile radius.
 * In Matthew Reilly's novella "Hell Island", the Island is overrun by 300 mountain apes who were genetically modified to be supersoldiers. They were controlled by silver disks, and anyone wearing one was immune to them. The island hadn't been overrun at all... it was part of an exercise. Schofield has Mother wipe out the disks, so nobody is immune, and everyone who was previously safe was killed by the apes, before Schofield drowned them.
 * Also in Ice Station when the one remaining French soldier attempts to take out the marines by planting a Claymore mine at a dead-end corridor. Rebound discovers his plan and turns the mine around, resulting in the gruesome death of the Frenchman at the hand of his own mine.
 * Somewhat amusingly, the aforementioned French soldier? His name is Jean Petard.
 * And later, the "bad guys" were themselves hoisted by not cleaning up the body of Petard.
 * In In The Penal Colony by Franz Kafka, the officer is killed by the machine he helped create. Somewhat subverted in that the officer went into it willingly.
 * A throwaway joke in one of the Discworld books mentions that it's not often that weapon inventors are killed by their own creation and the widespread belief in this happening is due to the unfortunate death of William Blunt-Instrument in an alley.
 * Also, in The Colour of Magic, Garhartra the Guestmaster casts a spell to stop a flung bottle of wine in mid-air. Eight hours later, he returns to the room just in time for the spell to wear off, and the bottle resumes its interrupted journey, smacking him on the head.
 * In Wyrd Sisters, Felmet commissions a play to slander the witches and make it so that people recognize him as king. Said play forms the perfect opportunity for the witches to meddle, and the ghost of the old king to possess an actor and tell everyone that Felmet killed him.
 * Lilly in Witches Abroad uses mirrors to amplify her powers. In the end she is trapped in her own mirrors, probably forever.
 * The vampires in Carpe Jugulum bite Granny Weatherwax in order to make her a vampire as well. Unfortunately, she sent her spirit into the blood they drank, so instead of transforming her they find themselves becoming more like her.
 * The villain in Feet of Clay attempted to poison the Patrician by using candles with the wicks soaked in arsenic. Vimes does the same trick with  in the climax. The villain also used a golem to help with the plot, and it's a golem that ends up arresting him.
 * Narrowly averted in His Dark Materials, where Mrs. Coulter is to be separated from her daemon by the same process she used on kids at Bolvangar, but manages to escape at the last moment. Arguably played straight immediately thereafter when her would-be executioner, still needing the energy released by the process and pressed for time, does it to himself.
 * Does it count if it's suicide?
 * Happens all the time in Stationery Voyagers, naturally.
 * The Xyliens capture dying souls and turn them into robots. Some of those robots rebel.
 * Alhox puts Bluque in charge of the war effort so that Alhox can focus on humanitarian concerns. Bluque launches a coup.
 * Bluque set up the entire thing because the Mystery Wanderer suggested it. The Wanderer then knows every security loophole, and uses it to trap Bluque and his army in the Muellex right after Bluque sent Alhox into exile. Leaving Markerterion with no leadership. But then, King Melchar's Evil Plan backfires. Turns out, sending almost your entire world's population to other worlds to wreak murder and mayhem can be a really bad idea.
 * Melchar's plan to have Alhox exiled results in Alhox joining the Voyagers just in time to destroy Drizad. What makes this especially bad is the fact that Alhox was the only one that was allowed by the cosmos to fight Melchar. Thus, Melchar gave the Voyagers the very tool they needed to have any hope of defeating him.
 * Varikton Vanqushun, like the characters that inspired him, has a huge problem with his plans backfiring. Kill your daughter for starting a charity organization? A whole La Résistance of Church Militants shows up. Try to suffocate and starve those Aviatets to death? They join forces with Commie Land and gain the weapons they need to defend themselves, and a motivation to fight. And then become a rival force of evil. Try to one-up those suckers and the human race simultaneously by stealing alien technology? A very pissed off, radioactive, kung-fu alien with a Mosquatlon, Violently Protective Girlfriend show up and blow your dictatorship to ash. And if you do succeed at stopping them, you'll have to deal with the Teal Fleet's wrath. Because the aliens you would've killed were carrying information vital to The Empire's plans.
 * By not counting on Viola's involvement in trying to foil the Buliod's-infecting scheme on Whixtitout, Astrabolo inadvertently allows Viola's ink to create a cure that renders Gel Pens immune to Buliod's disease. Therefore allowing one whole portion of the population of Statios to have one less reason to be afraid of Astrabolo.
 * Of course, Clandish "Cybomec" Consto. After having his only fuel rod removed, he still uses his electroblast to fry Pextel's librionic body. But this only has the effect of draining what little remained of Cybomec's own librionic energy and knocks him dormant. Thus, allowing the other Voyagers to defeat an otherwise unbeatable foe.
 * The Sherlock Holmes story The Adventure of the Speckled Band features a villain who dies after being bitten by the poisonous snake he intended to use to murder his stepdaughter so he could keep her money. Holmes even remarks that he is indirectly responsible for what happened when he hit the snake with his cane to drive it away, which made it retreat and bite its owner in anger, but says he's unlikely to lose much sleep over it.
 * In the Warhammer 40000 novel Grey Knights, the Big Bad Valinov is freed at his execution by Ligeia's death cultists and proceeds to use the servitor-mangler meant to kill him on Riggensen, who had succeeded in breaking him.
 * Basically, Warhammer 40000 stories tend to end due to the villain inevitably screwing himself over (unless he actually succeeds, which happens a lot).
 * Two books in The Demon Headmaster series do this. The first one is when the Headmaster falls into a machine that he uses to clone life, although that only lasts until the next book, where the machine clones him. The clone--who has the Headmaster's powers--is undone by an information overload in his brain.
 * In The Killing Star, both humanity and the our alien nemeses get Hoisted: first a race of aliens, whose only apparent purpose in the universe is to cause the deaths of others, nearly destroy mankind by flinging giant rocks at us at just under light-speed. Their reasoning? Because they heard "We Are The World" once centuries ago, and thought we meant it to say humanity was a unified nation that would attack them now that we have relativistic spaceships, because it seemed like a logical train of thought to them. One wonders how they ever got into space. In the end the humans nuke the Earth's sun, killing a good chunk of their fleet, and a few humans flee with the genetically engineered clone of Jesus Christ (no I'm not making this up...) into deep space, planning to retaliate when they get the chance.
 * To be fair, the motivation for aliens' genocide of humanity was entirely logical and rational (1. any species will place its own survival before that of a different species, 2. Any species that has dominated its planet will be intelligent, aggressive, and ruthless, 3. They will assume the first two rules apply to us).
 * It's logical...assuming you have perfect information on what you are up against, and there aren't "third parties" (other species) watching who punish the genocidal. Let's say, for example, that you hear my radio emissions, and decide to wipe me out. Oops! Looks like I had 100 systems settled to your one (or handful). Have fun dealing with my retaliation. Not only did you NOT wipe me out, but now I've gone from a "possible threat" to a "confirmed threat".
 * In Field of Dishonor, one of the villains is Denver Summervale, a professional duelist (and we're talking actual gun duels not happy go lucky card games for your soul). He hires himself out to kill people by goading his victims into challenging him to a duel and killing them there, where it's considered legal. When he kills someone close to Honor, her eventual response is to walk up to him, accuses him of murder-for-hire, goads him into challenging her, then shoots him down with contemptuous ease during the duel itself.
 * Mesa certainly has one of these coming, seeing as how their massive conspiracy to exterminate the Star Empire of Manticore and the Republic of Haven by keeping them constantly at war with each other has resulted in a massive, massive increase in the levels of technology employed by the Manticorans and Havenites. Well, as it turns out, Victor Cachat and Anton Zilwicki are very, very much Not Quite Dead, and the end result is that Manticore and Haven - whose space navies are now approximately a thousand times more Badass than they were - are teaming up to turn all that technology, skill, pent-up anger and experience on them. Essentially, Mesa is facing the single set of Allied nations in the galaxy that is ready, willing, and able to destroy them, and has spent the better part of a century honing themselves to do just that.
 * In The Dresden Files, Lord Raith has a fairly squicky predilection, which he ultimately becomes the victim of. Lord Raith, as a White Court Vampire, establishes dominance over his daughters by raping them and showing them that his mojo is more potent. His mojo, however, is also capped off and incapable of being refilled due to a death curse laid on him by Harry's mom -- who's also the mother of Lord Raith's son Thomas. Raith expends the last of his reserves trying to kill Harry and Thomas, which would break the curse... and provides the perfect opportunity for Lara to return the favor and use him as a Puppet King.
 * Big example in Changes on Red Court vampires who tried to curse Dresden's bloodline to death. To wit: the Red Court has the ability (through massive and incredibly difficult preparation) wipe out everyone within a certain bloodline, killing the sacrifice, all their siblings, their parents, all their siblings, their grandparents, their siblings, etc, etc. The plan was to use Harry's daughter to kill the Blackstaff, who is Harry's grandfather. Instead, Harry sacrificed the newest Red Court Vampire (who happened to be his lover) which wiped out every single Red Court Vampire that was still alive at that point.
 * In Ghost Story, this is how the Corpsetaker is finally taken down, as Mortimer Linquist, an ectomancer who she was torturing with hundreds of wraiths, seizes control of those wraiths and uses them to destroy her for good.
 * Another example occurs in Grave Peril. Bianca enlists the help of a few fellow sorcerers to stir up turbulence among the ghosts of Chicago, which messes with the barrier between the living and spirit worlds, allowing the ghosts to have a greater influence (i.e. cause more havoc) among the living world, for the sake of sending one particularly nasty ghost with a grudge against Harry after him. This backfires on her at the end of the book, when Harry uses that same turbulence to his advantage, empowering all the spirits of people killed by Bianca and her minions. The ghosts proceed to go wild and slaughter every member of Bianca's entourage, including Bianca herself (who was killed by the ghost of woman she killed but blamed Harry for, which is what set off her whole vengeance scheme in the first place).
 * Codex Alera has Kalarus, whose entire province becomes Alera's Pompeii when Gaius Sextus sets off the volcano he planned to unleash on the entire continent in the event of his defeat.
 * In Memory Sorrow and Thorn, forgemaster Inch spends a great deal of time torturing The Hero, Simon, by strapping him, crucifixion style, to the giant waterwheel used to power the forge's works. Simon manages to escape with Guthwulf's help; in the ensuing confrontation, Inch's belt gets caught in the wheel and he's carried off to his messy doom.
 * The Big Bad in Black Dogs summons a demon to destroy another character, but it backfires and demons, being the hostile creatures they are, attacks him instead.
 * Snot Stew: Toby teases the family's vicious dog Butch by leaping down into his enclosure and slipping out through a hole in the fence. He also bullies his sister Kikki by eating all of her food. Turns out these don't work well together, as he discovers when he tries to squeeze through the hole... and can't. Nightmare Fuel follows as Butch proceeds to maul his back end, with Toby screaming that he's eating him alive. He survives, but only because the humans rush him to the vet, and he loses his tail in the process.
 * In Robert E. Howard's Conan the Barbarian story "The Slithering Shadows", Thalis's Cold-Blooded Torture of Natala means Thalis is still there where Thog arrives to kill.
 * In The Hour of the Dragon, Zorathus tells Valbroso how to open his chest, without mentioning that if you do it with your bare hands, you will be poisoned.
 * To cash in on The Outer Limits franchise, a series of short Outer Limits children's books were released a few years ago. One of those books, The Lost, was about a rebellious teen who uncovers a conspiracy in her neighborhood where the adults are Brainwashing their own teenage children with a machine that changes their brainwaves into sensible, hard-working adults. Like any Cruel Twist Ending, she ends up brainwashed herself and becomes good-hearted and obedient, much to their parent's joy. Then she and the other teenagers take their parents (as well as the doctor responsible for administering the "therapy" in the first place) and subject them to their own machine out of the belief that they will be helping them become just like them.
 * In L. Jagi Lamplighter's Prospero Lost, the Three Shadowed Ones use Mephisto's Staff of Summoning against him and two companions, to summon a chimera. Mephisto goes "Hi, Chimmie!" and chases after them with its aid; the staff only summons, it does not command, and the chimera likes him better than them.
 * Quite a few baddies from the Nightside series have gone down this way, either having their deadly gifts backfire or turned against them by John and his allies, or suffering a Villainous BSOD that leads them to commit suicide with their own destructive powers.
 * In the Lilith War arc, Lilith resurrects the dead as an army to unleash upon the city and fight at her command. She overlooks the fact that one of the resurrected is, who turns out to be necessary to stop her.
 * Subverted in Harper Lee's To Kill a Mockingbird: it is officially claimed that Ewell fell on his own knife, but actually he was backstabbed by Boo Radley while trying to kill the children.
 * The Atrocity Archives has as its villains the remnants of an alternate universe's Third Reich. They managed to turn the Holocaust into a massive necromantic working, attracting the attention of a Great Old One they got to fight on their side. Thing is, after it destroyed the Allies, it proceeded to drain everything from the universe, to the point that said universe is facing imminent heat death only 60 years later and the Nazis are breaking into our universe in order to find a way to keep that from happening.
 * The victim in The Fairy Tale of Father Brown
 * In Artemis Fowl: The Opal Deception, Pixie Opal Koboi arrogantly declares that she has no need of magic when she has science, and has a pituitary gland surgically implanted in her skull so that her body will generate more growth hormone and make it easier for her to masquerade as a human child. The hormones generated by the gland sap her of the last of her magic just as she needs to use her mesmer power.
 * Her former partner, Briar Cudgeon, suffered a more fatal version of this. He activated the defense systems in Koboi Labs in order to stun the Bwa Kell crime ring after his plan to betray them was revealed. However, he was later thrown into the plasma powering the defense systems and was fried by the substance he had activated himself
 * In False Memory, the antagonist is a psychiatrist who mind rapes his patients and has them do all kinds of terrible things for his own entertainment. When things start to fall apart around him, he puts off a persistent patient (who has a pathological fear of Keanu Reeves) by telling her The Matrix is real, and she must hide from the machines.
 * Non-fatal example: In Too Many Magicians, the Marquis of London attempts to coerce Darcy into working for free to solve a murder, by using several pieces of circumstantial evidence to have Darcy's right-hand sorcerer, Master Sean, locked up on suspicion of the crime. Darcy turns the tables on the Marquis by explaining how the same circumstantial evidence could show probable cause that Lord Bontriomphe, the Marquis's right-hand man, was the culprit ... and that he had killed the victim on the Marquis's instructions. Foiled, the Marquis grudgingly pays Lord Darcy's expenses, Master Sean is released, and they join forces with Bontriomphe to track down the real killer.
 * In Death: A big moment of this is when Eve Dallas killed off her Complete Monster of a father with a knife while he was raping her. The interesting part is that she was only using the knife to cut some cheese to eat, and when he caught her and attacked her, she managed to grab the knife and pretty much cut him to pieces with it.
 * Goliath: In a moment of badassery, Alek kills Nikola Tesla with his own electrified cane
 * Grahame Coates, step up and be recognized! Grahame always fires his employees mere weeks before they have been employed long enough to qualify for the severance package. The exception: Fat Charlie Nancy, who has been working for Grahame Coates for an unprecedented two years. So, naturally, when Fat Charlie's brother makes Coates think that Fat Charlie is on to his long-running embezzlement scheme, Coates thinks that Fat Charlie would be the guy to pin it on. Fat Charlie is arrested and then promptly told by the policewoman interviewing him that it's laughably obvious that this has been going on for longer than even Fat Charlie has been working there, and he's being let go on grounds of being innocent.
 * In the Red Dwarf novel, an alternate reality evil Lister takes a massive dose of Luck Virus to protect himself from the Rage, a hive mind of fury that kills anyone it possesses. However, when he gets a taste of the Rage, as per its nature, he wants to be possessed by it more than anything in the world. And the luck virus has a way of granting one's deepest desires.
 * In John Lymington's novel Night of the Big Heat, spider-like aliens from another planet are heating up a Scottish island in the middle of winter, in order to better suit their preferred hot climate. It gets hotter and hotter until just when the entire cast seems doomed, the intense heat causes the island's trees and shrubs to catch fire. Although the humans escape unharmed, the aliens end up getting burned alive by the fire caused by the very heat they created.
 * In the 1967 movie adaptation, the screenwriter apparently felt that it made no sense for heat-based aliens to be vulnerable to fire, so that film's example of this trope has the intense heat created by the aliens (which are changed to energy creatures resembling living scrambled eggs) instead cause a storm, and the ensuing rain melts them all.
 * Comedy example: In Otherwise Known As Sheila The Great, Sheila and her friends booby-trap the bathroom toilet seat by coating it with toothpaste, hoping Sheila's sister will sit down without looking. Not only does it fail to fool Libby, but Sheila herself forgets about it overnight and gets a toothpaste-covered rear in the morning.
 * Inkspell: " "
 * In the D&D pick-a-path book Dungeon of Dread, the best ending has the Evil Sorcerer, who stocks his dungeon with monsters by transforming victims into them, gets transformed into a nasty little lizard/vulture critter.