Spanner In The Works / Fan Works

Spanners in the Works in Fan Works.

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Crossovers

• Ranma becomes one for not only Minaka and his Sekirei game in Anything Goes Game Changer but Higa as well, the latter without even being aware of the man's existence. Besides Ranma interfering with unfair battles, mostly preventing Sekirei from being forcibly winged, he and Uzume pose for pictures for Nabiki to raise money (to cover his living expenses). Uzume's cut is enough for her to pay off her Ashikabi's hospital bills, which were being used by Higa to blackmail her.
• Avatar: The Last Alicorn: Sweetie's plan to take over Fillydelphia and eliminate all the water and fire benders along with the avatar and the great dragon would've gone perfectly, if it wasn't for AJ learning metal-bending, allowing her to escape, and provide Team Avatar an avenue to escape.
• Avengers: Infinite Wars:
  • As the narrative unfolds, it becomes clear that the Avengers are this for Palpatine's plans, as their existence outside the Force makes it hard for him to predict what they will do or their impact on events.
  • Chapter 44 implies that the Guardians of the Galaxy are this from Ultron's perspective, at least in the sense that they represent an unknown factor in his plans as he can't explain Quill's obvious Terran origins or Rocket's very existence.
• The Bridge (MLP) gives a borderline humorous example in an otherwise completely serious situation. Bagan has set up an elaborate Xanatos Gambit that would work out in full to both secure more power for himself as well as kill Harmony. A crux of it was keeping a displaced Monster X separated from his comrades and put into the Equestria Girls world, where he'll be weaker in his human form and thus easier to kill by Bagan's agent, Enjin. One bystander messed it up and they weren't another kaiju nor an Equestrian hero intervening in the fight. EG!Photo Finish happened to be at the scene of a battle between X and Enjin at a hospital and took some pictures, thinking it was a movie stunt being filmed. Days later when an ally of X was in the same realm but dozens of miles away, she bumped into Photo, saw the pictures and recognized X in the images; and was able to alert her allies that she'd found him and he was in trouble. Bagan, the billions year old Physical God got his plans set back by a photographer who didn't even know what she was snapping pictures of.
• In Cardcaptor Rad, the Decepticons plan to invade the Autobot base actually works. They likely would have succeeded in attaining the Star Saber if not for the humans and mini-cons being there.
• The Choices of Earth: Agent Johnson and the Torchwood team’s other government contacts are completely caught off-guard by the Doctor’s involvement in the situation.
• The Chronicles of Tanya the Holy: Tanya ends up being a massive spanner for not just the Lich King, but for the whole plot of Warcraft III. First is her actions in Stratholme where she calls upon Being X and purifies all the infected villagers on top of crippling Mal'Ganis. Then in Northrend, Tanya stops Arthas from taking up Frostmourne and psychically damages the Lich King. Besides Arthas never joining the Scourge, the Alliance is reformed, Quel'thalas is never sieged, the Burning Legion doesn't return, and the Horde and Night Elves become trading partners, though the last part doesn't last.^*Because Lordaeron never fell, the survivors didn't have to flee to Kalimdor. Without Grom fighting the humans, Thrall never sends him north to Ashenvale, so Grom never incurs the wrath of the Night Elves and Cenarius. Eventually the two factions go to war because the Night Elves refuse to let the Horde harvest enough lumber to support their nation. In the epilogue, it's revealed that Tanya threw things off so much that the Bronze Dragonflight went insane and had to be put down after they started attacking the Alliance in an attempt to set things back on the "correct path".
• Code Geass: Paladins of Voltron: C.C. following the Paladins to the Castle of Lions is this for Charles and Marianne, as this puts her beyond the range where the latter can track her.
• Death Note Equestria: Mer ends up going off Twilight's script in order to ruin her in revenge for Rarity's death as a part of one of Twilight's earlier gambits. Subverted, however, as Twilight had actually anticipated this and factored it into her plans, resulting in Twilight's triumph and Mer's death.
• In crossover fanfic Displaced (TheMountainJew): Spider-Man's arrival in Gotham City and his meddling with a Joker's heist accidentally causes an unprecedented gang war all across Gotham.
• Earth's Alien History:
  • The Bolshevik Revolution crippled the Illuminati's ability to act in Russia, as its agents there were all members of the bourgeoisie and were thus purged.
  • The Doctor's interference gives the allied forces enough of an edge that the Mekon War is cut considerably shorter than it would have been otherwise, including preempting the Mekon's planned attack on Earth. It later turns out that this is the Point of Divergence between the main timeline and the Mirror Universe.
• Equestria Girls: A Fairly Odd Friendship:
  • Zephyr Breeze is this a couple of times. His streaking causes the Rainbooms to discover Timmy's magic, upending the FOP status quo and starting the plot. Later, he tells Sunset about Timmy being at the skate park after she told him not to go, while he had a magical clone to distract her.
  • Played for Laughs with Dinkleberg. He obliviously has the Rainbooms' van towed away with them in it, preventing them from discovering Cosmo and Wanda's existence.
• The Fury of a Storm basically makes Luke Smith (The Sarah Jane Adventures) this to the plans of the 456 (Torchwood: Children of Earth); as Luke is technically two years old despite being physically in his teens, he is able to pick up the signal, which gives Torchwood another means of investigating it, while Luke's enhanced mind allows him to use the link to "attack" the 456 in turn, to the extent that he survives transmitting the signal to destroy the 456.
• Guardians, Wizards, and Kung-Fu Fighters:
  • During the Battle of Torus Filney, the Rebellion's strategy hits a major stumbling block when Simon shows up, due to not having planned for his presence. But then they're able to turn the tables on Servantis' forces when they reveal that they have guns.
  • Cedric and Wong's plot to betray Phobos and steal the Heart of Meridian from him catches Nerissa completely off guard, throwing her own plans completely Off the Rails.
• In Harry Potter and the Alien Reality, Harry represents an unexpected factor to most villains faced by the SGC as none of them are used to facing magic, although SG-1 take care to ensure that Harry doesn’t do anything to expose his magic to the Goa’uld even if the NID are aware of his magic.
• It happens quite often in Infinity Crisis, considering that the multiverse is now a resource to draw from.
  • Thanos himself is a spanner to many groups' bigger plans, as his snap ended up derailing, revamping, or changing how villains' plans were across the multiverse.
  • Mephisto himself was the spanner to Thanos's idea of retiring, pushing him to take further actions, and leading to his downfall.
  • Amora and Agatha both had good things going in Storybrooke and could easily use any new outsiders with ease. However, Evie and Mal immediately pick up on the personality incongruities for Regina, and thus begin their journey to find out what's going on and then tear it down.
  • The "Wild Card" sets herself to be one, observing multiple universes, plucking selected people from them, and hiring them as employees, in order to fulfill ominous goals concerning the entire Multiverse.
• Just an Unorthodox Thief: The incarnation of Lupin III that gets summoned into the Fourth Grail War effectively sets out to derail everyone's plans as much as possible.
• In Kage, Yua predicts Jade's presence in Meridian will cause Nerissa's plans to go Off the Rails, and any attempts by the elderly sorceress to force Jade to fit in her plans will only cause the schemes to unravel further. Jade is also this to the second season timeline in general, with the changes already starting to add up.
• Know Thyself: While Voldemort was a carefully crafted factor in the machine's plans, Harry surviving his encounter with a scar and Voldemort's code being scattered from it was such an anomalous event, agents had been keeping a close an eye on him to ensure that he wasn't a threat up until the point that Trinity found him. Not only that, but the machines didn't even notice his absence at first because he is the only wizard to have been successfully unplugged, all other attempts rendered in a vegetative state.
• In the How to Train Your Dragon / Marvel Cinematic Universe crossover series Loki'd, Thor being banished to Earth was this for the plan to replace Laufey on the throne Jotanhiem with as few causilities as possible. Instead of a nice clean precision strike to take out Laufey's war council using the bifrost generator, it resulted in Thor's friends bringing Thor back to Asgard only for Thor to interpret Loki's actions as an attempt at genocide and prevent Loki from shuting off it off before there was widespread distruction and mass causilities on Johanhiem.
• In The Man with No Name, during the final confrontation with the Big Bad, River basically serves as this; after his opponent tries to break through the Doctor's psychic shields, River is able to turn the tables by getting into the other alien's head while his psychic barriers are down so that he can break the Doctor's, the Doctor acknowledging that a disadvantage of psychic combat is that both sides have to let down most of their defences which can leave them open to attack from another angle.
• Metal Gear: Green: The MSF serves as this for the HPSC. Within the span of nine years, the MSF have dismantled the Los Hermanos Cartel, killed off the Congo Tyrant, erased the Showstoppers, and have been successfully draining the HPSC of power and resources, causing no ends of frustration for Madam President. For bonus insult, the reason the MSF is in the MHA world is because of the HPSC's ambitions.
• My Hero Academia: Unchained Predator: The Steel Sabers and League of Villains sponsor, Wolfram, had such a perfect plan: Take over I-Island, steal all the support items, then kill everyone there while doing a ransom demand to buy more time. This would devastate Hero society. It all failed because the Sabers stumbled upon the Slayer's hideout by accident and Wolfram felt as if that wasn't important to tell Nine about. As a result, the Slayer's actions resulted in the annihilation of the Steel Sabers.
• Daniel Jackson (Stargate SG-1) serves as this to the plans of John Cavil/Number One (Battlestar Galactica (2003)) in "Seven", as Daniel is the last of the Number Seven Cylon models and is able to expose the extent of Cavil’s insanity and manipulations to the other Cylons.
• A Spider's Evolution starts when the Brotherhood and the X-Men were both attempting to recruit Rogue (X-Men: Evolution, "Rogue Recruit") only for Spider-Man to get involved in the confrontation, which leads to Rogue basically choosing him over the two teams.
• In Spidey-Team, Peter Parker of the Marvel Cinematic Universe has been part of the Spider-Verse crossover, with the result that he is already aware of the multiverse before he meets Beck and thus knows that Beck can't be a dimensional traveller as he doesn't know anything about the rules (such as how Beck "should" be glitching if he's been in another dimension for two weeks).
• Spider-X: Mystique's immediate plan to spend time with Rogue as Risty and her and Magneto's more long-term plan to infiltrate the manor and pose as Xavier are both thwarted just because Peter Parker joins the X-Men, as his spider-sense makes him aware of Mystique's true identity even when she isn’t explicitly doing anything dangerous (although she doesn't actually know how he sensed her for some time).
• Star Wars Vs Warhammer 40 K: The Imperium of Man's sudden and violent arrival to the Galaxy Far, Far Away has unknowingly severely disrupted Palpatine's plans. They are a piece on the board that the Sith Lord has no control or influence over. Their presence means he can't move against the Jedi as he needs them to help defeat their forces. In addition, the Imperials have forced Palpatine to redeploy most of the Republic fleet to protect Coruscant. This not only allows General Grievous to effectively defeat the Outer Rim Sieges but also weakens Palpatine's control of the Senate due to the outrage many Senators feel over their planets and systems being abandoned.

Buffyverse

• Harmony acts as one in We're Doomed to Marcie Ross and her plans to murder the popular kids as revenge. Namely, when Cordelia is running from the invisible monster trying to kill her, she runs right in front of Harmony's car who swerves to avoid her, right into Marcie. Harmony also ruins the plans of the organization seeking to recruit Marcie.
• Xander in Xendra functions as a spanner on a cosmic scale. Not only can Drusilla the Mad Seer not See him and thus can't counter his plans, but he's shown to be immune to prophecy, leading to him breaking three or four prophecies, including Jasmine's plan to be reborn via Cordelia.

Case Closed

• Dominoes has a particularly cruel one during the climax of its first arc. Kaito steals the Meta-Nullifier from Shinichi. As a result, Shinichi can't use it on Santa, the boy unintentionally causing the Black Hole Crisis. ISHA orders an airstrike on their location; Kaito saves Shinichi at the last second, but Santa is left to die.

Charmed (1998)

• "Tempus Fugit" reveals that Cole unwittingly affected the Triad's plans for the Jenkins sisters when he (apparently) vanquished the Triad's physical bodies. The Triad planned to leave Christy to be abused by other demons and then step in to "rescue" her so that she would regard the Triad as her protectors and become their loyal servant, but when Cole turned on them, their "deaths" meant that Christy was lost in the Underworld all over again.

Danganronpa

• Danganronpa 2/3 Redux: Return Unto Death: In the third chapter, Monokuma intended to set up a corruption arc for Akamatsu Kaede. However, during a confrontation, Kazuichi accidentally injures her while rejecting her apology. As a result, she goes to see Mikan for treatment, only to walk in on a murder scene, forcing Monokuma to make the brainwashed killer murder her as well.
• Danganronpa: Yakuza Arc: In Part 2, Hajime proves to be one for Hideki; all of their plans get derailed when Hajime wins their duel. Being beaten by a high schooler, and only walking away from their fight because Hajime chose to spare him, completely wrecking his reputation and any momentum his intended clan war had built up.
• In Despair Arc: Execution Failed?, Kyoko and Makoto ruin Junko's plan before it even gets off the ground, as Kyoko's investigation leads her and an accompanying Makoto to discover a still alive Chiaki before she succumbs to her gruesome wounds. This, in turn, leads to not only 77-B being snapped out of Junko's influence, but Izuru returning to being Hajime.

Death Note

• Nobody Cares About the Receptionist: Light's plan to dispose of Naomi Misora goes awry when one of the NPA receptionists notifies Aizawa that the chief's son is leaking information about the Kira investigation to a random stranger.

Digimon

• In Digimon Adventure 02: The Story We Never Told, Ken serves as this for Oikawa; even after his death, Ken's D3 undid his brainwashing of the other Digidestined's partners.

Fairy Tail

• Ironically, Black Wizard Zeref becomes one for one of Grimoire Heart's plans in Fall of the R-System. His arrival to destroy the R-System a cult was making distracted and kept Ultear from brainwashing Jellal with a false ghost of Zeref.
• The AU fic Lost Magic is an interesting example. While the deliberate wrench in Jellal's plans is Simon, the one whose mistake actually set his plot derailing was Jellal, himself. By accidentally getting himself pregnant with Erza's child.

Fate Series

• Chaos Theory opens up with this. It introduces the plots and manipulations of all the antagonists of FSN, and then the narrator calmly declares:
  But mostly? The assorted plans at play here would be going very, very wrong due to the actions of a no-name, no-count, utterly talentless Magus by the name of Shirou Emiya. He had no magic worth mentioning, no combat experience of note, and no plan for or knowledge of the War he was about to enter. He did, however, have one trait that had derailed a countless number of such grand, far-reaching schemes throughout history.
  You see, he really, really wanted to be a hero.
• Fate/Harem Antics: The entire fic is about Irisviel, who is trapped in the Holy Grail but in full control of it, deciding to use the upcoming Holy Grail War to get her son Shirou a harem. All the existing plots and plans promptly get derailed as Iri makes sure all the Masters and Servants besides Shirou are female. Specific examples are:
  • Iri's father planned to summon Hercules as a Berserker and force his granddaughter Illya to serve as Master. Iri summoned Minamoto no Raikou instead. Likewise, Iri has some limited ability to speak to her daughter through the Grail, so unlike in canon where Illya hated Shirou and their father (because her grandfather lied to her), Illya knows that their father never abandoned her, and is looking forward to meeting Shirou.
  • Bazett tried to summon Cú Chulainn as Lancer, but Iri gave her Scáthach instead. More importantly, when Kirei tried to murder Bazett for her Command Seals, Iri briefly stopped his artificial heart, distracting him at a critical moment and ruining the opportunity.
  • Sakura summoned Medusa as Rider, as in canon. Zouken tried to force Sakura to give control over to her brother Shinji, but Iri deliberately made the summoning more explosive than usual, causing the ceiling to fall on Zouken. Sakura and Rider escaped in the confusion.
  • After Zouken recovered from having a ceiling drop on him, he summoned a Servant himself, deciding an Assassin would fit him best. Iri gave him Hassan of Serenity, a Poisonous Person. Zouken didn't realize that, slapped her for her perceived disobedience, and melted. And since Iri had severed his connection to Sakura (which she could only do after Sakura made her contract with the Grail), he couldn't draw power from her and stayed dead for good.
  • Iri did this to herself with Assassin: Since the intent is for Shirou to have sex with all the girls, the fact that she can't touch anyone without killing them is a problem. Iri quickly summons Sir Galahad as Shielder, who has the power to resist poisons and can pass this on to her allies. And she makes Caren, Kirei's long-lost illegitimate daughter, her Master just to mess with Kirei.
  • And Iri again manages to do this to herself. By summoning Shielder and Ruler, she broke the normal limits on number of Servants and left the door open for others to be summoned. Three separate groups start summoning Servants of their own. Iri can't shut them down, but she can make sure the Servants and Masters are all female. She gives the Ainsworth family Jeanne Alter as Avenger, but instead of letting Julian become the Master as they intended, she grabs his sister Angelica. She gives Fiore of the Yggdmillennia clan Oda Nobunaga (who is female in the Nasuverse) as Gunner. And Miyu wasn't trying to summon a Servant at all but didn't understand how the Grail War worked and got Elizabeth Bathory as Temptress.

Gargoyles

• In Kimberly T's Gargoyles series, Thailog’s plans in "Deadly Moon" are derailed by the unexpected factor of Heinrich, a gargoyle newly-arrived in New York from Germany who saw Thailog tormenting Anne and the children and literally landed on Thailog from above.

Godzilla

• Abraxas (Hrodvitnon): Godzilla is a secondary character rather than the protagonist of this story, but he kicked off the entire plot when he ripped San's head off of Ghidorah during the events of Godzilla: King of the Monsters (2019). Ghidorah was keeping an Only Mostly Dead Vivienne inside of San's head with plans for her, but Godzilla decapitating San ensured that the version of San's mind in his severed head along with Vivienne survived Ghidorah's destruction during the movie, and, cut off from the influence of Ghidorah's other two heads, San had to hybridize and merge with Vivienne on his own, while the severed head with San and Vivienne inside it fell into the hands of Alan Jonah and his mercenaries. On the downside, the continued existence of San's old decapitated head has also ensured that Ghidorah itself isn't permanently dead yet.

Harry Potter

• In Harry Potter and the Nightmares of Futures Past, the reason why Peter Pettigrew's plan to cause chaos at Hogwarts (see Western Terrorists) fails is because the Gryffindor Six and some other students know how to use the Patronus Charm.

How to Train Your Dragon

• In A Thing of Vikings, Berk suddenly gaining control over dragons upsets the balance of power in Europe and derails many plans already in motion. Wulfhild notes that Hiccup pretty much changed the rules of the game overnight and forced everyone else to play catchup.

The Hunger Games

• In The Golden Mean, Finnick sadly laments that many of the victor-tributes who died in the arena, the mentors who died when Peacekeepers came to arrest the rebels, and many people killed in Districts 4 and 12 when the Rebellion broke out might have survived if not for an oblivious Capitol worker spotting the hovercraft meant for the escape and kicking things off early in a desperate scramble,

Jackie Chan Adventures

• Queen of All Oni: Jade's otherwise flawless Operation: Steel Lightning only fails because of the presence of Agent Wisker, who she didn't know and couldn't plan for. He doesn't stop her but slows her down long enough for Uncle to catch up with her and beat her.

Kung Fu Panda

• In The Vow, when Po and the Furious Five have been imprisoned in the dungeon of the Tower of the Sacred Flame and Shen prepares to spring his trap for the invited nobility of China, Lianne sends Jade to free the heroes before they can be killed, allowing them to rescue the nobility, setting back Shen's plans of conquest a little.

Love Hina

• An Alternate Keitaro Urashima repeatedly derails his grandmother's attempts to manipulate him simply by letting others know how manipulative she is. As a result, when she shows up and starts spinning her webs, she winds up proving him right.
  • Mokoto also runs afoul of this when she threatens Keitaro one time too many. When she draws her katana, she's unaware that some police officers are passing behind her and witness it.
• For His Own Sake:
  • Granny Hina and Mutsumi regard Nagisa as this, blaming her for disrupting their plans for Keitaro.
  • Along similar lines, most of the Hinata Girls see Keitaro as this after he Grew a Spine and left the inn, forcing them to start facing actual consequences for their actions. Part of this is simply by warning others about them, ensuring that they know what they're dealing with.

Lyrical Nanoha

• Nanoha's presence in Game Theory derails Precia's carefully laid plans. But this turns out to be a subversion, because the events that disrupted Precia's original strategy actually made it possible for her to come up with a better plan that works flawlessly.

Marvel Cinematic Universe

• A Real Chance opens with Uatu witnessing He Who Remains prune over a hundred timelines where at least one of the other Avengers spoke with Wanda before she went to Westview, or at least reached out to her before she "committed" to the idea of using the Darkhold to try and get her family back. Despite Uatu's vow to only observe, after witnessing He Who Remains express such satisfaction at how the TVA have cut Wanda off from so many allies in so many worlds, Uatu sends Wanda a discreet telepathic warning Wanda that she and Peter Parker are about to be attacked in the final timeline the TVA were to prune, featuring the two meeting in London as Wanda followed up a lead on the Darkhold and Peter happened to see her after the battle with Mysterio. With this advance warning, Wanda and Peter are able to fight their attackers off and affirm they'll be alert for the future, creating a new timeline where Wanda not only rejects the Darkhold but also prevents Spider-Man's identity being exposed.
• Dream Until Your Dream Comes True has Wanda see a bit more of the world she was dreaming of with Tommy and Billy, resulting in her learning that in that reality her counterpart was almost lobotomised by the Illuminati before Peter Parker stepped in to defend her from their fears that she was going to be another threat. Curious about "her" Peter, Wanda goes to visit him just in time to witness his first meeting with Mysterio, prompting her to read Beck's mind and learn about his own knowledge of the multiverse... which naturally exposes that he's a fraud in time to stop him doing any real damage.

Marvel Universe

• In Ultimate Sleepwalker: The New Dreams, the Green Goblin kidnapped and planned to publicly murder Gwen Stacy as a way to get revenge on her father, Captain George Stacy of the NYPD. While Spider-Man intervened and tried to rescue Gwen, the Goblin had anticipated that and set things up so he'd be able to kill both Spider-Man and Gwen at the same time. Unfortunately, what he didn't take into account was Sleepwalker following Spider-Man to the top of the bridge a Cascnd distracting him long enough for Spider-Man to rescue Gwen and get her to safety. The Goblin proceeded to have a Villainous Breakdown.

The Matrix

• In Rescue Run, Captain Dena Reese unknowingly serves as this to the Machines' cycle of control to keep the human population of Earth under their control; not only does she confirm that the Matrix has existed for longer than the two centuries the people of Zion believed, but she also helps them make contact with the human colonies in the rest of the solar system. Through her presence, the people of Zion are evacuated from Earth and relocated to a new green planet, while the spacefleet destroys the Machine mainframe and the Matrix to prevent the machines from following them into space.

Miraculous Ladybug

• Burning Bridges, Building Confidence:
  • Cole's entrance into Francoise Dupont makes it significantly harder for Lila to get away with any of her schemes. Since Marinette warned her ahead of time, Cole makes sure to gather plenty of evidence, such as recording her threats and having proof of her own movements.
  • Cole also makes things much more complicated for Chat Noir. Not only does she call him out on being The Load, she exposes his exploitative behavior to Master Fu, who isn't pleased to learn that Chat Noir is deliberately skipping out on fights to try and Blackmail Ladybug into 'admitting she loves him'. As a new permanent bearer for the Fox, Vexxin proves to be the loyal and trustworthy partner Ladybug needs, proving that she doesn't have to rely on somebody who refuses to take their heroic duties seriously or acts entitled to her.
  • Adelaide becomes one after Alya attacks Cole. Upon learning what kind of abuse Marinette and Cole have been dealing with at school, Adelaide immediately takes action against the district, resulting in Ms. Bustier potentially losing her job, Alya's reputation going up in flames, and the exposure of Lila and her followers.
• In Cat Out of the Bag, Luka ruins Adrien and Plagg's scheme to guilt-trip and manipulate Ladybug simply by being present. After witnessing Chat Noir's argument with Ladybug and abandoning the Ring, he reveals to Marinette that he already knows both of their secret identities. They then go back to her room so that he can explain how he knows — namely, how Adrien intentionally got hit by another akuma's powers, forcing him to become a Secret Secret-Keeper while using Second Chance to rewind time and prevent the knowledge becoming public. When Plagg shows up, he points out the kwami's attempts to blame Marinette for everything, pointing out how illogical it is to claim that she's somehow "cheating" on Chat Noir by calling upon other heroes... especially when Plagg accidentally reveals that Adrien was deliberately skipping fights because he was too busy jealously sulking about her becoming less reliant upon him.
• Coffee Catastrophe features Adrien acting as one when he impulsively swipes Lila's phone after she tries to spill hot coffee all over Marinette and her sketchbook. Plagg then helps him unlock it and send her mother evidence of all her lies before sneaking it back into her bag. Nobody considered him as a possible suspect, and all his friends are astounded when he finally fesses up.
• The Dad Villain AU was created by Hawkmoth winning and making a horrifically spiteful Wish: that the magical backlash created from Emelie using the broken Peacock Pin would be redirected towards Ladybug's loved ones, forcing her to watch as she lost them one by one until she was the only one left to suffer the backlash herself. However, he has to contend with a few of these:
  • While Gabriel Wished that he would be the only person with Ripple-Effect-Proof Memory, the Wish uses Exact Words against him — all of the kwami and sentimonsters still recall the original timeline, since he doesn't consider any of them to be people. This enables Felix and Kagami to scheme against him, as well as bring his son Adrien in on the loop and reveal to him that he's a sentimonster as well.
  • Nooroo proves to be the biggest living wrench thrown into his plans. Gabriel saw him as nothing more than his helpless victim — not powerless, but only in the sense that his Miraculous granted him plenty of powers to abuse as he saw fit. This underestimation enables Nooroo to steal his own Brooch and escape the Agrestes, making his way to the Dupain-Cheng bakery and empowering Tom instead. And as a further side-effect, Tom having the Butterfly Brooch protects him from suffering any magical backlash from the Peacock Pin.
• Feralnette AU: Lila gets hit with two of these at once during the Birds of a Feather arc. Firstly, Principal Damocles defies all expectations by actually listening to Marinette's side of the story rather than letting Lila completely control the narrative. Then when she insists that Marinette should be expelled, Damocles casually reveals that Chloé has claimed Marinette as her tutor, and made clear to him that if he kicked her out of school, she'd set her father's fury on Francoise Dupont.
• The Karma of Lies: Gabriel Agreste has a secret emergency fund account which he uses for various purposes. Unfortunately, this is also the only one of the Agrestes' accounts Adrien is able to access — and thanks to Gabriel being such a Control Freak, his son knows very little about money management or basic precautions. Adrien accesses the account in full view of Lila, who memorizes the passwords and secretly cleans him out... making the account effectively useless not just for Adrien but for Gabriel and Nathalie, both of whom intended to use that money to their own ends.
• Scarlet Lady:
  • The whole series is kicked off by Chloé's decision to steal the Ladybug Earrings out of Marinette's purse. She has no clue about their significance; she was just looking to punish her favorite bullying victim for daring to stand up to her and assumed the box was some kind of family heirloom. As a result, she becomes the Nominal Heroine Scarlet Lady, leaving Master Fu at a complete loss as to how the Earrings wound up in the hands of a complete stranger.
  • Kim's plans to ask Ondine to officially become his girlfriend are scuttled when Chloé happens to come across him waiting on the bridge. Chloé immediately makes a big scene out of rejecting him, dramatically harping on and on about how uninterested she is — and ignoring all protests that the gift wasn't meant for her. Ondine comes across this, gets told by Chloé to leave because "I'm trying to turn down this loser!", and flees the scene, leading to Kim getting akumatized into Dark Cupid.
• In this untitled one-shot, Lila leaves her homework binder at home with the intention of framing Marinette for its "theft". Unfortunately for her, her mother notices it and swings by the school to drop it off, only to witness her daughter's plan in action. Mrs. Rossi then angrily calls out her daughter for lying again, then proceeds to ensure that she'll have to repeat the year in order to make up for all her absences, as well as dealing with the fallout of her exposure.
• In this series, Adrien tries to paint Marinette as a bully for refusing to let Lila's Malicious Slander go unchallenged. Unfortunately for him, Felix witnessed the tail end of him confronting Marinette, and knows that the only reason she slapped Adrien is because he was gripping her arms hard enough to leave bruises behind. His testimony convinces Alya to check Marinette's arms and find said bruises, exposing Adrien as a Bitch in Sheep's Clothing.

My Hero Academia

• Anyone: The police chief's plan to give Endeavor the credit for taking down Stain is ruined by the villain behind the Hosu attack uploading video footage of Anyone fighting the serial killer.
• Conversations with a Cryptid:
  • Midoriya discusses this with All For One, as he discovers that something must have happened for the murderous supervillain to put his plans on hold. All For One cryptically says that plans can change. In fact, it was because of his marriage to Inko and Midoriya being born that caused All For One to change his plans so he could stay with them and/or keep them safe.
  • Another spanner is the Sludge Villain who proceeds to kidnap Midoriya, eventually resulting in All For One breaking out of prison to rescue his son.
• Juxtapose: Shouto runs into one during the Sports Festival. As in canon, he intended to beat the strongest person in the tournament purely with his ice side in order to spite his father. However, he fixated on Katsuki as his target and is thrown off by Momo beating Katsuki in her fight. This leads him to assume that he can breeze through the remaining competitors, not taking his semi-final opponent seriously... and enabling Hitoshi to take him by surprise and score a victory.
• Mastermind: Rise of Anarchy: Monoma's efforts to tempt more alumni from U.A. into joining Mastermind's side is complicated by Mustard, who isn't in on the plan and promptly starts antagonizing his targets the moment he meets them.

My Little Pony: Friendship Is Magic

• Echoing Silence: When Celestia banished Twilight, she thought that Twilight was on the verge of going Nightmare, and either would fully transform, or be returned to normal by guilt, either of which Celestia had plans to deal with. Unfortunately, the changeling invasion prevented Celestia from looking for Twilight right away; not only did it interfere with that, it also bought Sombra time to return and regain control of the Crystal Empire. By the time she's finally able to track Twilight down, years have passed, and Diadem has put her past far behind her.
• The Great Alicorn Hunt proves to have this as a natural side-effect; with more alicorns ascending, they end up unintentionally disrupting a lot of antagonists' schemes.
• The Pony POV Series has one that's notable for the exceptionally long time required for the spanner to actually get into the villain's works. Back in the G3 Universe, which was facing The End of the World as We Know It (actually a Shoot the Dog to avert a Class Z Apocalypse) at the time, Pinkie Pie's best friend Minty just bled to death after their fight with Luna, leaving behind her "spirit" (or at least a piece of herself). Strife, Discord's sister and Spirit of Natural Selection, is fighting the survivors of the doomed world (in order to give them at least the chance to fight for their survival, something she believes is the right of all living things) and sent Heartless-like spirits of "erased" ponies after them. One of these falls into the canyon where Pinkie and Minty's fight took place, wounded in battle. Pinkie, in a split-second choice, fuses the piece of Minty with the shadow, which turns out to be that of the G1 Twilight. The result? Twilight Sparkle!
  • During the Dark World Arc, Discord's little sister Rancor is this. She arrives to get close to Discord and ultimately steal back Destruction's power from him so it can be used for its intended purpose (Destruction's original job as an Anthropomorphic Personification), mortally wounding him in the process. This ends up throwing a gigantic wrench in Nightmare Eclipse/Paradox's plans, allowing Discord to Out Gambit her and alert Twilight to the true nature of the Dark World, forcing Paradox to expose herself to the heroes. The name Rancor chooses after succeeding (Disruption) couldn't be more appropriate. It's this trope especially because, while it's implied she knew Paradox was there, she didn't care one way or the other what happened so long as her own mission was a success.
  • Part 6 of Shining Armor's Arc has Sergeant Thunderchild be this General-Admiral Makarov's attempt to kill Shining Armor. Makarov didn't even know his name, yet he shows up just in time to break through Makarov's Anti-Magic field and save Shining. This also buys time for more Shining's forces to show up in a Gunship Rescue and drive Makarov's forces off.
  • During the Wedding Arc, Prince Blueblood inadvertently foils Queen Chrysalis' plan just because he wanted to take a girl on a date. He led his date through the caves under Canterlot, and ended up finding the imprisoned Princess Cadance.
• Slice of Velvet and Pear: Princess Celestia expected her student in this timeline, Moondancer, to go on the same journey and discover friendship in Ponyville, as Twilight Sparkle did in canon during the events of Nightmare Moon's return. But there's two problems she didn't count on; Moondancer has even less social grace, tact, and interest in other ponies than Twilight did at the start of the series. Leading to her quickly alienating herself from Ponyville's residents and attempting to go after The Elements of Harmony on her own. And two, Moondancer's old classmate, Twilight Sparkle. Who in this timeline, is already living in Ponyville with her friends and was never Celestia's personal student and there go, not somepony she particularly factored into her plans. Who In Spite of a Nail, winds up going through more or less the same journey with her friends they did in canon after chasing after Moondancer to try and help her. Resulting in The Element of Magic being split between Twilight and Moondancer. Something Celestia did not expect and does not know what to make of when she arrives.

Naruto

• Five Petals diverges dramatically when Sakura shoves Sasuke out of Orochimaru's way and gets bitten instead. Orochimaru didn't intend to give her the Cursed Seal, and while he initially dismisses her as a 'minor' setback whom he expects will prove unable to survive the seal's presence, she proves herself to be a persistent thorn in his side, causing him to spiral through a series of Villainous Breakdowns.
• Team 8: In Chapter 17, Kurenai tells Naruto to use his chakra pulse to dispel the genjutsu Kabuto put on the stadium. Naruto overpowers the pulse so much it ends up covering the entire village — causing Orochimaru's plan to fall to pieces twice over, as not only did it dispel the jutsu that were going to summon the giant snakes, it also destroys the barrier he had put to prevent people from interfering with his duel with the Third Hokage.
• your move, instigator (draw your weapon and hold your tongue):
  • Team 14 surviving mission after mission enables them to serve as a set of Morality Pets for the older shinobi of Konoha, as their presence makes it harder for them to ignore how they're using Child Soldiers. Their effectiveness only increases once they're the Sole Survivors of their respective graduating classes, leaving very few children under ten alive save for the clan heirs.
  • Danzo finds one of his plans working against him after Sai escapes from ROOT; they promptly take advantage of the Propaganda Machine by producing new posters and graffiti encouraging Konoha to question the Sandaime, promoting Minato as a potential replacement.

Neon Genesis Evangelion

• Advice and Trust: Shinji and Asuka end up ruining Gendo's plans by befriending Rei, although this happens long before his plans are put into action. And everyone is completely unaware of the implication of this, meaning that they spend several chapters trying to figure out how to stop him, and he still thinks that he's in control of the situation, despite the fact that he's already lost.
• The Child of Love:
  • Gendo thought he had planned for any contingency, but he did not foresee his son's involvement. Shinji sleeping with Asuka forced him to modify his plans and it ensured that Yui would want to protect his son’s family and Rei would get involved in ways Gendo would not like.
    Fuyutsuki: But you said that this project was 100% planned, right?
    Gendo: There was only one mistake on my part. I won't let that happen again.
    Fuyutsuki: You mean...your son?
    Gendo: Yes. I didn't think that the Second Child would use the Third to 'satisfy' her boosted hormones...this was a big mistake, and may result in complications.
  • In chapter 9 Fuyutsuki warned him that he had not accounted for everyone and someone would stop him, but Gendo did not listen. Cue Rei interfering. And then Yui.
    Fuyutsuki: I think you're forgetting about someone. Someone who won't forgive you for this, Rokubungi Gendo...
• Doing It Right This Time: Asuka has grand ambitions to being this after realising she's in a Peggy Sue situation, but the one to take the biggest direct step towards derailing the Scenario is Rei... and to a lesser extent, the late Naoko Akagi. Shinji still needs some convincing that they can pull it off.
• HERZ: SEELE's attack in 2015 failed because another secret organization accidentally learnt about their plans and interfered with them… something SEELE had not counted on at all.
• Higher Learning: Gendos plan started to unravel when a teacher offered counseling to the Children.
• Rise of the Minisukas:
  • Not only was the appearance of the Minisukas completely unpredictable, but also they are gradually messing up with Seele's plans by altering the outcome of the battles and hacking their bank accounts.
  • Aoba is the only potential time-traveller who Gendo has no prepared countermeasures for, due to him being a wildcard. Unfortunately for Gendo, he is too useful to get rid of.
  • Downplayed with the Minisukas' attempt at helping win the Angel War, which runs for the most part on them being a Peggy Sue to the NGE timeline and runs into the complication of the Angels getting additional powers, running different tactics, and even being from different Alternate Timelines.
• In RE-TAKE, SEELE finds all their plans foiled by something they could never have anticipated Shinji be aided by Ghost-Asuka and "God" which allows him to destroy the Mass Production Evas during the fan-fic's take the events of "End".

One Piece

• This Bites!:
  • The Unluckies. If the Point of Divergence in Chapter 19 wasn't enough, in Chapter 20, Cross attempts to use Soundbite's powers to stop or stall the Rebel Army outside of Alubarna. Unfortunately, the Unluckies arrive and snatch the snail, scrapping that plan. And even after they're beaten, Miss Friday manages to disable Soundbite's powers until Luffy beats Crocodile.
    • For a while, it actually became something of a Running Gag that the Straw Hats' plans never worked out as planned, to the point that the characters started making note of it in their planning sessions. This was particularly frustrating and humiliating for Cross, as he is the official tactician for the crew. But starting after Skypiea, things start going much better.
  • Granny Kokoro proves to be this to Cross's plans. Sloshed out of her mind, she browbeats Iceburg and Franky into feeling the love that the Going Merry has for her crew, and encouraging them, as Tom's apprentices, construct a ship worthy of the Oro Jackson's successor... within earshot of Iceburg's secretary and one of his best shipwrights.
  • Aokiji. Post-Enies Lobby, when he came across an island hosting a big pirate brawl, he decided to halt the whole thing with an Ice Age... giving Blackbeard the perfect opportunity to swallow up his now-frozen opponents.

PAW Patrol

• Zuma's Fear: Believe it or not, Zuma ends up screwing Stone’s Evil Plan after the death of his family.

Pokémon

• In AAML: Diamond and Pearl Version, it is noted that Misty is basically this to Paul’s efforts to undermine Ash; during their battle at Lake Acuity, when Paul accuses Ash of bringing in his strongest Pokemon because he knows his training method can’t beat Paul’s, Misty reminds Ash that he raised his powerhouses to their current level using his traditional training, matching Paul’s reliance on force with experience and compassion.
• Pokémon Mystery Dungeon: Lost Tracks of Time: By befriending Sneasler, Ingo and Emmet inadvertantly prevented her from getting chained at the same time as the other Nobles, preventing the Big Bad from getting the 18 Plates they needed to usurp Arceus. Special mention goes to Emmet for removing the Red Chain from Ingo before it took effect and stealing the Toxic Plate from Sneasler when she is successfully chained.

Puella Magi Madoka Magica

• A History of Magic: The Incubators feared that this would happen in the form of an Anomaly, a person who has magical powers not granted by them, for they could awaken the magical powers in all of humanity. It was why they had arranged for Jesus to be crucified, after all. Their fear was eventually realized when Billy Kane used Haitian magic to become a Puer Magi, causing a chain reaction that resulted in thousands of teenagers spontaneously becoming Puer and Puella Magi without contracting.

RWBY

• Children of Remnant: Fifteen years of indoctrination by Salem begins to be undone by Yang deciding to throw the Claimed a party.

A Song of Ice and Fire

• And the Giant Awoke: When Euron and Tywin make their plans for dealing with each other — raid into the other's lands to force the enemy to retreat and fight in their own terms — all of them are for nothing when a storm forces both fleets to change course and they meet in the middle of the sea.
• Ned Stark Lives reveals that Jaqen H'ghar had been hired by the Great Other to kill Jon. Arya's presence in the Night's Watch caravan completely derailed that plan, though.

Star Wars

• In Exchange Star Wars, Obi-Wan and Anakin being swapped with their younger/older selves acts as this to Palpatine's plans; the older Anakin and Obi-Wan are able to more easily deal with the threat on Naboo while the presence of the younger Obi-Wan and Anakin forces Palpatine to expose his true agenda before he was ready to save his life.
• The escape sequence in Revan's Story is a series of spanners caught in other spanners. Like in canon, the protagonists anticipate capture by the ship Leviathan, so they each come up with a plan to escape and free the others. Unlike in canon, Darth Bandon throws a wrench in their plans. First, he stops HK and T-3's plans because he recognizes Revan's personal assassination droid, and orders his troops to wipe their memories and physically restrain them in case the wipe doesn't go deep enough. Second, he stops Jolee's plan to Jedi Mind Trick the guard into solitary confinement because he knows what the trick looks like. Third, he senses Juhani sneaking through the Force and overpowers her. Canderous's plan of faking his death is eliminated for being risky, and Zaalbar is absent. Only Mission's plan goes undetected by virtue of not starting until she's away from Bandon, and even then she's almost caught. The party isn't recaptured because Admiral Karath, the last spanner, was also The Mole.

Super Mario Bros.

• In Clash of the Elements, Fawful, Alpha and Mario are this to Cackletta's plans. And Bowser too, for freeing the Star Spirits from their imprisonment.

Supergirl

• Hellsister Trilogy: During the Apokoliptian War, Darkseid is always at least three steps ahead of his enemies, and he comes very close to win. His plan only fails because of one factor he couldn't have foreseen: Supergirl being near D'reema right when he spoke the Anti-Life Equation. Before succumbing to the Anti-Life Equation, which destroys Free Will, Kara had just enough time to hypnotize D'Reema into speaking the opposite Equation, thus cancelling out its effects.
• Kara of Rokyn: Lex Luthor's plan to kidnap his sister Lena and his nephew fails because his enforcers accidentally stumble on Captain Strong, who looks like a regular old guy but is in fact a vicious, super-strong street brawler. Knowing nothing about him, they underestimate him and are brutally beaten up.
  Luthor's enforcers had learned to respect superheroes and never take a foe for granted. Chances are, the old guy facing them was tough, a brawler, but they could handle that. They were also three or four to one, depending on how you counted the Siamese twins, Pluto and Plato Statler.
  The problem was, nobody had ever briefed them on Captain Strong.

Superman

• Adventures of a Super Family: Lex Luthor's plan to destroy an upcoming company rival by sabotaging its experimental plane engine during an exhibit gets foiled when an unknown super-hero suddenly shows up and saves the plane.
  The plan had been so straightforward as to almost be laughable. Sabotage the plane's engine, making it crash, then blaming it on the new navigation system. Sure, any engineer worth his salt would say that a faulty navigation system would not make an engine explode, but with the plane splattered across half of Metropolis and a few hundred people dead in the crash, no one would have listened. The company would have never recovered from this public relations disaster.
  But the plan had not worked. All because some comic book superheroine had chosen that exact moment to step into the limelight. Was this a joke? Was some cosmic deity playing a prank? The world gains a superhero just in time to sabotage his plans?
• New Beginnings (Smallville): After being exposed, Clark intends to go back a few days in order to discredit Linda Lake's before she can out him. Linda's interference, though, causes him and Lois to travel all the way back to 2001.

Teen Titans

• Jewel of Darkness: The only reason Midnight's plan to torture Robin to insanity fails is because Ai betrays her on orders from Trigon, something she couldn't have possibly anticipated.

Ten Little Roosters

• In this fancomic series, every one of Barbara's attempts (and traps) to murder their Rooster Teeth colleagues is foiled due to the others' sheer dumb luck (with a few cases of taking a level in intelligence). The result? Everyone ends up surviving:
  • Michael's poisoned glass breaks before they have a chance to drink from it.
  • Gavin and his clone manage to catch themselves, preventing them from falling in the mousetraps.
  • None of the arrows wind up hitting Chris.
  • When reaching for the extra gun, Burnie spots the scorpion and shoots it.
  • Gus slams the door on the Killer.
  • Adam trips over a cord just as the Killer is about to strangle them.
  • The puma decides they're more interested in being petted by Lindsay than mauling her to death.
  • The part of the treadmill that Miles is glued to breaks off completely.

Transformers

• Black Crayons;
  • In A Child's Innocence, Annabelle tells Megatron that she thinks Dylan Gould and Sentinel Prime are responsible for what is happening in Chicago. This serves as a blow to Megatron's ego as he takes this to mean that the Autobots and their human allies see him as less of a threat and that Dylan and Sentinel have overshadowed him. This leads him to attack Sentinel to reassert his status. Note that Annabelle really does believe that Dylan and Sentinel are the ones responsible for what is happening in Chicago based on what she was told and has no idea that Megatron is actually the one who is behind everything.
  • In Not According to Plan, the teenagers' plan to make anti-Cybertronian propaganda would have gone much better if Annabelle hadn't decided to join the other kids that were going to be in the propaganda.
    • Wheelie also throws a wrench into the works by uploading an unedited video of Annabelle and the other children befriending him all over the Internet.

Victorious

• Mid-way through Start from Scratch, Jade has been convinced to return to Beck after running away from his drunken abuse to stay with Tori, as Beck's demonstrated that he's genuinely trying to change to the extent that he's able to show her his sixty-days-sober chip. However, when Jade runs into a casting agent she recently had an audition with while out for a walk, the agent mentions that she was told Jade couldn't accept the past as she had to have surgery. With this as a catalyst, Jade checks back regarding a couple of other recent rejected auditions and realises that Beck has been sabotaging her auditions with the goal of breaking her spirit so that she won't have the "incentive" to be anything more than his meek, devoted wife.

Worm

• Atonement: The Slaughterhouse Nine might have gotten a new member in Ruin had Mnemosyne not interfered, turned Burnscar against the rest of the Nine, and freed Hunter.
• Quicken: Emma accidentally and inadvertently causes a gang war only because she was in the wrong place at the wrong time wearing the wrong clothes.

X-Men

• Devil's Diary: Before his first outing, Magneto looked into the then-current cadre of heroes and villains and decided neither of them would want or be able to stop his coup. Yet still he was driven away by five heroes whom nobody had previously seen before... although he KNEW who they were working for.
  Damnable adolescent yearlings, every one of them, like the beardless youths Hitler put against the Allies when all his other defenses were cracking. Except these yearlings had power. None of them equal to mine, individually. But they knew how to effectively combine what they had. And they had luck, three times damned three times luck, and NO ONE HAD EVER SEEN THEM BEFORE.
  All mutants.
  Three males, one female, and one snow-being whose sex is impossible to determine at this point.
  An unknown quantity.
  An x-factor.
  A XAVIER FACTOR.

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