Sandbox / For Want of a Nail

Examples for the Trope Idea Salvage Yard listing for a "Minor change leads to major consequences that are shown explicitly" trope, salvaged from this TRS thread for For Want of a Nail.

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Anime & Manga

• Digimon Ghost Game:
  • There's a good bunch of incidents that wouldn't even be solved if not for the protagonists incidentally getting involved. One variant is the protagonists going on a vacation only to run into the offending Digimon (or rumors of), and the other variant is someone they know personally, often an acquaintance just happened to be the victim or one of the victims. This includes horrific incidents that would lead to dozens of deaths at best and humanity being wiped out or enslaved at worst, so they did save the world just because they are in the right places at the right time.
  • Digimon Ghost Game E54 "Second Sight": The dangerous accidents Octmon's Fujitsumon predicted are not rigged unlike Publimon's "newsletter", they are real mishaps that are about to strike the likes of Kotaro or Gammamon. Had he just not went into an argument and drove away his Fujitsumon on accident and one of them latched itself onto Hiro, there's a very high chance Gammamon, Kotaro, Aoi and at least 24 other people would've been hurt or worse.
  • Digimon Ghost Game E61 "Resurrection": The Digimon responsible for the incident the One-Shot Character was in is no ordinary Digimon but a Moon=Millenniumon. So had she not called the protagonists into her house to investigate some hauntings and a moving corpse, the entire world would be annihilated.
• Dragon Ball Z: If Guru hadn't died when he did, it's very likely that Vegeta would have gained his wish for immortality (assuming Dende wouldn't wish for something else entirely).
• Happy Sugar Life: As Satou and Shio prepare to leave for the airport, Satou notices she left her ring behind in her old apartment, and they go back to retrieve it. This leads to them being caught by Asahi and culminates in Satou giving her life for Shio. For want of a ring, Satou gave up everything.
• Redo of Healer: Norn does indeed manage to develop a strategy that completely counters and overwhelms Keyaru's machinations in the defense of Branicca, and it would have crushed him like a bug, except for the fact that the messenger she entrusted to deliver her orders never made it to the front lines, intercepted by Keyaru himself.

Films — Animation

Films — Live-Action

• Dragged Across Concrete: Kelly ould have survived the events of the film if her husband had allowed her to stay home with their newborn baby for just one more day. Hell, even if she had taken a later bus and showed up later than she did, she would have made it.
• The Jungle Book (1994): The film's opening has three examples of this trope, and all of them are connected to Buldeo.
  • Had Buldeo and those two British sentries not killed some animals for the heck of it, Shere Khan never would have attacked the garrison.
  • Had Nathoo stepped aside and allowed Shere Khan to kill Buldeo, Shere Khan would have considered the matter settled and departed without causing any further damage.
  • Conversely, Buldeo could have prevented the rest of the movie from happening if he had simply shot the tiger when Nathoo gave him the chance (and encouragement) to do so, instead of running away like a coward.

Literature

• Overlord (2012): Elf King Decem Hougan's capture and rape of Faine is what causes the Slane Theocracy to start a century-old-war against the Elf Kingdom, with many of its residents being kept in the dark about it.

Professional Wrestling

• A.J. Lee: HOLY CRAP, her decision to hire Brad Maddox as a referee during her GM tenure seemed so insignificant at the time. Until you think about how things could have gone company-wide if Maddox wasn't hired.
  • With no Maddox nut-punch to Ryback, Ryback becomes the WWE Champion in October 2012, ending CM Punk's title reign three months early and taking a huge bite out of his career bragging rights by cutting him off at 343 consecutive days, not 434. It's also possible that with no title to defend, Paul Heyman never makes the call to a certain trio of black-clad vigilantes, drastically altering their story arc as well. And given Ryback's Badass Decay only happened after his issues with the Shield, who knows how long Ryback would have held the title…which might have done some serious card-scrambling at the Royal Rumble, where we could have had a returning Rock against Ryback or someone else entirely as opposed to Punk.
  • As for Maddox himself, he stays in NXT, doesn't get noticed by the McMahons, and doesn't become A.J. Lee's successor as GM. ^note Vickie Guerrero was the de facto GM after AJ resigned, but Brad Maddox was the next to actually hold the true and permanent title.
  • One must wonder what would have happened to the careers of herself and Daniel Bryan if not for the infamous 18-second Wrestlemania XXVIII loss to Sheamus. One could argue that this one sequence was the difference between each of those two being in the strong Ensemble Dark Horse category to gathering the momentum to being the most popular Superstar and Diva in the company respectively.
• Pac: During an episode of RAW, he accepted an open challenge for Seth Rollins's WWE Championship. At one point, he actually hit the Red Arrow on Seth, and actually would've gotten the three-count and won the WWE championship had he not accidentally moved Seth's foot on the ropes.
• Volk Han: If Han's trainee Fedor Emelianenko is to be taken seriously, had Han not been sick in his fight with Nogueira, he would have won the fight. Granted, Fedor might have been simply putting over his master, but when you watch the match and see Han trading holds with the young Brazilian, it is not farfetched at all.

Video Games

• Digimon Survive:
  • The routes diverge during the Kenzoku attack on the Amusement Park's Castle and how the characters react to it:
    • In the Moral route, Miu managed to remember about the trap door she used back in chapter 4 in-time. As such, the group stayed together and starts a fighting retreat. After the battle, Takuma and the professor choose to remain in the Throne Room in an attempt to snap Miyuki out from the Master's possession, but he increases his grip on her and attempts to kill Takuma, only for Jijimon to Take The Bullet. This results in his death, but no humans are dead or rendered insane in the encounter.
    • In the Harmony route, Miu failed to remember the trap door in time, resulting in Kaito rushing off to fight the Kenzoku, with Miu following after him. Saki then noticed some Amusement Park monsters that had yet to be saved and rushed off to save them; Aoi decides to send Minoru to find an escape route, while she and Takuma followed after Saki. Takuma manages to both save the Amusement Park monsters and arrive in time to fend off the Kenzoku for Kaito and Miu, but the fog thickens and a stray Kenzoku taking the form of one of the Amusement Park monsters lures Miu to be preyed on before Takuma, Kaito and Miu can regroup with the others. This resulted in Miu's death and Kaito going insane.
    • The Wrath route is similar to Harmony route in set-up, the difference being Aoi's response; she sends Takuma to help Kaito and Miu, while she and Minoru rushes off after Saki, who was being lured in by Kenzoku disguised as Amusement Park monsters. Takuma, Kaito and Aoi manage to defeat all the Kenzoku, but one of the defeated Kenzoku springs back up to ambush and kill Saki, resulting in her death and Aoi going insane.
    • In the Truthful Route, because of Shuuji and the Professor successfully researching the murals in the Shrine, rather than going to the Amusement Park to ask Jijimon about the Kenzoku (which always fails and causes one death), they go find Baihumon in the same place for answers instead. The invading Kenzoku are all fended off with no casualities and thus the Amusement Park remains intact due to the Master failing to kill Baihumon, and the party manages to both get some concrete answers of what's really going on from Baihumon's partner and Baihumon's good side.
  • The Nail for the Truthful Route is Kunemon managing to save Ryo and snap him out of his insanity. This leads to Ryo saving Shuuji and Lopmon, snapping the former out of his self-destructive and toxic behavior. As the team doesn't lose members, this continues to cause a ripple effect the rest of the game.
  • The entire story turns out to be kickstarted by one of these. A few centuries ago, after Haruchika and four others are thrown into the Kemonogami World as sacrifices by the acting priestess, she did not use her powers to return to the Kemonogami World and meet her younger brother Haruchika again. Turns out she was only too busy with her duties and died of old age before she can enter the other world, but her brother already took it as a betrayal. The end result is a horrible Serial Killer who has probably murdered a massive amount of children spanning across a few centuries over a misunderstanding that could had been cleared with some communication.
  • Downplayed for Shuuji. In the Truthful route, he helps the Professor try to make sense of the murals found in the inner shrine, including the meaning of the bizarre composition of the mural on the third level. Shuuji's aid helps the Professor realize the Kemonogami depicted on the mural are the Four Sovereign Beasts and what their role is, setting the events of the route into motion.
  • It doesn't become readily apparent until much later in the game, but in the Truthful Route, Ryo's survival causes the story to deviate for the better. Not only does Ryo's survival spare Shuuji from cracking under pressure more than he already has, but Ryo starts to lay into him for treating Lopmon poorly.
  • Kunemon saving Ryo's life in a New Game Plus run has massive ramifications on the rest of the game, compared to how the kid's situation spirals out of control in a normal playthrough. Ryo's presence at Shuuji's emotional breakdown proves instrumental in bringing him back from the brink of despair, which leads to Shuuji finding a new role and father figure in assisting the Professor's research, which leads to the mystery of the alternate world being solved.
• Dragon Age: Kal'Hirol is discovered to have fallen due to an incomplete gear mechanism for one of the massive doors used to seal the Deep Roads. If it had been completed before that section had been overrun by darkspawn, it's possible that Kal'Hirol could have survived much like Orzammar and Kal-Sharok.

Web Video

• Don't Hug Me I'm Scared: Stain Edwards, the Forever Boy, was originally meant to merely be the raw material to make a new friend from a friend-making kit from a selection of templates. The only reason he developed his own personality was because Yellow Guy knocked him and the kit off the table during a fit of grief.

Western Animation

• Big City Greens:
  • "Welcome Home" (the chronologically first episode): If Cricket had just listened to Bill and stayed in the truck, then it wouldn't have been towed in the first place.
  • "Raccooned": If Cricket and Bill remembered to close the door before entering the garage, the raccoons wouldn't have taken over their house in the first place.
  • "Remy Rescue": If Tilly didn't run off to get a board game and sneak into the vent after seeing Vasquez escaped, Remy would've left Cricket for good.
  • "Mama Bird": Had not Cricket been present when the birds hatched, they wouldn’t have imprinted on him in the first place.
  • "Wild Side": Cricket couldn't have gone loose in the city in the first place if Bill had just taken him out of the city into the woods (like in "Gridlocked") like old times.
  • "Green Acres" (the Origins Episode of the Green Family): Had not Bill and Alice taken up Mr. Quisling's offer, then Big City wouldn't have expanded and built around the house, Bill would not have married Nancy, Cricket and Tilly wouldn't have been born, and none of the series' events would've occurred in the first place.
  • "Sellouts": If Gloria hadn't posted a picture of one of the Greens' chickens, this wouldn't have given her the idea how to save the Greens' stand by teaching them to go social.
• The Simpsons: Episode "Marge in Chains". Had Marge not been in prison, she could've helped out with the bake sale to raise money to buy a statue of Abraham Lincoln, instead of the Jimmy Carter statue which angered the citizens so much a mass riot broke out.

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