History Main / KeyStoneArmy

** It's given a nod in ''VideoGame/XCOMEnemyUnknown''. After you take an alien base, your NumberTwo believes that you've broken the invasion. The Head Researcher, however, raises an eyebrow at that, mutters under her breath something about "Too easy", then walks off to begin researching the spoils. [[spoiler: She's right. Turns out the base was only an ''outpost'' of the main force. Played straight, and Justified, at the end of the game however. Taking out the [[FinalBoss Uber Ethereal]] kicks off a reaction that [[LoadBearingBoss causes the alien]] [[TheMotherShip Temple Ship]] [[LoadBearingBoss to implode]], taking the majority of their ships, supplies, and leadership with it.]]

Similar, but not to be confused with the ''[[Creator/KeystoneStudios Keystone Kops]]''. No relation to UsefulNotes/{{Pennsylvania}}'s[[note]]which is known as "The Keystone State"[[/note]] National Guard.

** Whenever a Gohma leader is killed, all its subordinates die automatically. [[spoiler: Taken UpToEleven when their god Iemanis is [[DidYouJustPunchOutCthulhu killed]] in Season 3, the whole species goes extinct.]]

* ''WesternAnimation/StarWarsRebels'' reveals that [[spoiler:while the shutdown command on the droid army released after Order 66 did take into effect, [[TheStrategist super tactical droid Kalani]] received the command but, thanks to his calculations, determined that it was a [[AntiMutiny trick by the Republic]] and choose ''[[AvertedTrope not]]'' to shut down himself or the troops under his command. Apparently, he was the only, or at least one of the only, droids who determined something was fishy about the command]].

* In ''TabletopGame/{{Chess}}'', the king is all that matters.
* The same goes for the Japanese game of Shogi, which is not unlike Chess.

* In the ''Film/TotalRecall2012'' remake, the BigBad is making an army of robots to take over the only other habitable area in the world. The protagonist finds out about a shutdown code for the army buried in his memories. When LaResistance leader tries to access the memory, this triggers a hidden code that allows the BigBad to find him. Also played straight when the protagonist destroys [[spoiler:the Fall, a gravity elevator from Europe to Australia, destroying the robots aboard]].

** And done in "The Best of Both Worlds" when the ''Enterprise'' rescues Picard/Locutus, who they use to destroy the Borg Cube...by telling them all to "go to sleep".

* ''Film/{{Oblivion 2013}}'' : [[spoiler: After the Tet gets blown up, the drones immediately deactivate.]]

* The rogue robots in ''Film/IRobot''. [[spoiler:Since VIKI was remotely distorting their programming to make them hostile to humans, they immediately became docile upon her defeat.]]

* Arguably in ''Film/TheLastStarfighter'', the Xodan Command Ship's communications turret. It is what allows the entire armada of space fighters to coordinate. Without it, they're not as effective and taken out quickly with a MacrossMissileMassacre thanks to the Death Blossom.

* ''Film/TheMummyReturns'': The unending army of Anubis turns to dust when the title's Scorpion King is killed and ordered to take his army with him. Justified, because whoever kills the SK, [[YouKillItYouBoughtIt becomes the legitimate master of the army]]. The good army is just preventing the anubites from getting out into the world, they knew they couldn't win on their own.

* ''Film/{{The Avengers|2012}}''. Destroying the mothership causes all the aliens to drop dead. In the DVDCommentary, Creator/JossWhedon admits that he hated having to resort to this trope, [[EnforcedTrope but it was]] [[NecessaryWeasel necessary]] to give the heroes a clear victory instead of battling for seventeen more hours of cleanup.

** Reused in ''Film/IndependenceDayResurgence'' where [[spoiler:after killing the alien queen, all of the aliens immediately drop dead and the mothership leaves Earth.]]

* In a 1970s Comicbook/{{Avengers}}, ComicBook/{{Thanos}}'s space fleet is attacking Earth. It turns out that all of the multivaried aliens in the fleet are depending on a single gizmo on one ship to translate for them so they can understand each other. The Avengers destroy it, and then win fairly easily. Somewhat justified when it turns out that Thanos [[XanatosGambit arranged the whole thing]] as a distraction from his ''real'' evil plan, and didn't especially care whether the space fleet succeeded or not.
** Even Thanos' actual evil plan, using the Cosmic Cube to make himself a god, turned out to be this. Captain Mar-Vell (alongside a small group of allies made up of Drax the Destroyer, Drax's daughter Moondragon, Thanos' brother and father, as well as Iron Man) is hopelessly outmatched by the all-powerful Mad Titan, especially after he uses the Cube to become one with the cosmos. However, Mar-Vell realised that despite becoming a RealityWarper, his power was still in-flux and reliant on the Cube. Thanos tried to age him into dust, but with his dying breath Mar-Vell managed to strike the Cube and [[ResetButton undo Thanos' changes]]. As a side-effect, Thanos was turned to stone, dead. The members of his forces that remained on his flagship and ''weren't'' members of the distraction fleet then scattered and fled without him to lead them.

* ''ComicBook/JudgeDredd'': In the ''Judgment Day'' arc, the villain Sabbat's zombie army is entirely dependent on his continued control to function. The Judges of the world's Mega Cities eventually assemble a strike team to take out Sabbat in a last-ditch effort to prevent the Earth from being destroyed completely.

* In the climax of ''WesternAnimation/FelixTheCatTheMovie'', when Felix [[ThrowTheBookAtThem throws the Book of Ultimate Power at the Master Cylinder]], the Duke of Zill's entire army of cylinders and cubes explodes. Poindexter surmises that the Master Cylinder was the PowerSource for the army, and it reacted adversely to the book's gold binding. Felix believes there may have been more to it than that.

* In the climax of ''WesternAnimation/FelixTheCatTheMovie'', when Felix [[ThrowTheBookAtThem throws the Book of Ultimate Power at the Master Cylinder]], the Duke of Zill's entire army of cylinders and cubes explodes. Poindexter surmises that the Master Cylinder was the PowerSource for the army, and it reacted adversary to the book's gold binding. Felix believes there may have been more to it than that.

* Several ''Anime/{{Doraemon}}'' films have the heroes' victory in taking down a single element controlling the invading army leading to their immediate victory:

* ''VideoGame/Stellaris'': The [[AIIsACrapshoot Contingency]] has 4 Sterilization Hubs. Destroying them will reveal Nexus-01, which is the primary core of the Contingency. Destroy Nexus, and all their ships, stations and armies are destroyed.

** Even more so with Norn Queens. Apparently, poisoning one can make entire tendril with multiple Hive Ships defenseless, at least for a while.