Hoist by His Own Petard/Playing With

Basic Trope: The villain is defeated and killed by his own weapon or plan.
 * Straight: The villain produces a grenade and prepares to throw it at the hero, but it 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.
 * Justified: The weapon has some kind of defect the villain didn't anticipate.
 * The weapon had an inherit flaw that the villain could not fix.
 * Inverted: The hero's weapon backfires, killing him. The villain is completely unharmed.
 * Subverted: The villain's weapon backfires, but he is Not Quite Dead and uses it again to kill the hero.
 * Doubly Subverted: The hero is also Not Quite Dead and manages to use 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.
 * Deconstruction: 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.
 * Reconstruction: Unfortunately for him, the villain is just highly incompetent at using it.
 * Averted: The villain eschews weaponry, preferring to kill his victims with his bare hands.
 * 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 that it'll eventually overheat and explode, killing him.
 * Alternatively: See Driven to Suicide.
 * 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 redshirts. 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 learn from all the bad guys who've blown up using their own devices before them."
 * Conversed: "Wow, the villains in these stories really need to institute some tighter quality control checks."

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