Playing With / Hoist by His Own Petard

Basic Trope: A character (usually a villain) who is defeated and possibly killed as a result of his or her own plan, weapon, etc.
  • Straight: The Big Bad produces a grenade and prepares to throw it at The Hero. It turns out, though, that he threw the pin, and the grenade explodes and kills him instead.
  • Exaggerated: The villain has constructed a death ray on another planet and is planning to destroy Earth, but it explodes, destroying the planet he is on.
  • Downplayed: A gambit intended to give the villain some advantage as part of a larger plan backfires, dealing the villain a temporary setback.
  • Justified:
    • The weapon has some kind of defect the villain didn't anticipate.
    • The weapon had an inherent flaw that the villain could not fix.
    • The villain really WAS that dumb and it was only a matter of time.
    • The villain was not dumb at all and knew about the risk. He simply took a gamble and lost.
  • Inverted:
    • The hero's weapon backfires, killing him. The villain is completely unharmed.
    • The villain sends the hero on a Wild Goose Chase. This saves the hero's life when he's not there when the villain's base blows up.
    • The Knight Templar villain takes a poison to avoid being captured and questioned. Unbeknown to him, the air was carrying a poison gas, and they act as mutual antidotes, leaving him still alive.
  • Subverted: The villain's weapon backfires, but he is Not Quite Dead and uses it again to kill the hero.
  • Double Subverted: The hero is also Not Quite Dead and uses the villain's weapon to kill the villain, for good this time.
  • Parodied: The villain's weapon kills him... because he had his head stuck down the barrel trying to see why it wasn't working.
  • Zig Zagged: A couple of the villain's Zany Schemes backfire non-fatally, and others are just Crazy Enough to Work. Ultimately, the villain does die, though not necessarily by means of his own making.
  • Averted:
    • The villain's death is not the result of his own weapon.
    • The villain's weapon does not backfire.
    • The villain does not die; for that matter, maybe The Bad Guy Wins.
  • Enforced: "We've got to have the villain beaten somehow! Let's just make his machinery backfire."
  • Lampshaded: "I knew... I should have gone... with the extended warranty..." [Villain dies]
  • Invoked:
    • The heroes provoke the villain into firing his weapon repeatedly, knowing it will eventually overheat and explode, killing him.
    • Driven to Suicide
  • Exploited: Bob designs a weapon, but before using it, he realizes that it will backfire, so he tricks his enemy into using it instead.
  • Defied:
    • "Minion, make sure that the engineers double-, triple-, and quadruple-check that device. I don't want it to blow up in my face when I'm using it."
    • Alternatively: All dangerous machinery is operated by Mooks. All powerful weaponry is built so that it can only aim outside the fortress.
  • Discussed: "How come these villains always make their machines so shoddy? You'd think they'd have learned from all the bad guys who have blown up using their own devices before them."
  • Conversed: "Wow, the villains in these stories really need to institute some tighter quality control checks."
  • Implied: There is talk in the background about a new handheld explosive being detonated during one scene with the villain. A while later, the villain has a robotic replacement arm.
  • Deconstructed: The villain's weaponry comes complete with inherent flaws and is highly unstable, meaning that it could kill anyone at any time; it's a turkey shoot whether it'll even work properly. The villain is aware of this, but the villain is willing to take that chance.
  • Reconstructed: Unfortunately for him, the villain is just that bad at using it.
  • Plotted a Good Waste: The series has been building up around fate and how things are already decided. The Big Bad, deciding to Screw Destiny, uses copious resources building up a new weapon that would allow him to break the chain of events and kill the heroes early. He misuses it so badly he loses his arm as prophesy says the fight would go.
  • Played for Laughs: The villain's attempts to kill the hero fail. Every. Single. Time. Even when all the flaws are worked out.
  • Played for Drama: Betty, who suffers depression, decides to try a small practical joke involving a water balloon at the urging of Alice. When it ends up soaking Betty, she gets worse.

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