History Main / PerpetualMotionMonster

* [[LivingShip Reapers]] in ''Franchise/MassEffect'' can operate a seemingly infinite amount of time without the resupplying other ships need constantly. This gives them a rather considerable advantage against everyone else. It's generally assumed that whatever it is they're using for fuel, it's based in [[SufficientlyAdvancedTechnology technology beyond the understanding of their targets]].

* The [[ImplacableMan Dahaka]] from ''VideoGame/PrinceOfPersiaWarriorWithin'' fits the role.

* Corprus infectees in ''[[VideoGame/TheElderScrollsIIIMorrowind Morrowind]]'' suffer massive, [[BodyHorror uncontrolled muscle growth]], to the point where they can apparently survive by cutting off their own tumors and eating them.

* Alex Mercer and James Heller in the ''{{VideoGame/Prototype}}'' games are stated to have no need for food or rest and only [[IAmAHumanitarian absorb]] people to heal major wounds.
* [[LivingShip Reapers]] in ''Franchise/MassEffect'' can operate a seemingly infinite amount of time without the resupplying other ships need constantly. This gives them a rather considerable advantage against everyone else. It's generally assumed that whatever it is they're using for fuel, it's based in [[SufficientlyAdvancedTechnology technology beyond the understanding of their targets]].

--> ''They don't eat, they don't sleep, WHAT KEEPS THEM GOING?''
* Robots in the ''VideoGame/{{Fallout}}'' games. By ''VideoGame/Fallout4'' it's been more than 200 years since the war that destroyed civilization, but you'll still find plenty of Mr Handies and Securitrons operating at full power despite a lack of access to any apparent fuel sources. Ghouls, despite being alive, are occasionally treated this way as well: there are multiple instances in the game where you'll encounter feral ghouls that have been trapped inside a room without a food source since the bombs fell, and they're still very active.
* Doomguy in ''VideoGame/Doom2016'' and onward is a player equivalent of this. Canonically he does not need food, drink, or rest, thanks to the enhancements in his body allowing him to subsist off of the essence he absorbs from the demons he slays. The result is a OneManArmy running on a perpetual RoaringRampageOfRevenge to slaughter Hell and its forces whenever they arise. He's so unstoppable and unceasing in his crusade that ''[[TheDreaded Hell itself fears his brutality.]]''

* Robots in ''VideoGame/{{Kenshi}}'', unlike every animal and sentient species in the world, don't need any food. This being a SurvivalSandbox game, not needing any food and therefore not having to devote money, manpower and resources to feeding yourself is a ''major'' advantage.
* ''VideoGame/WarcraftIII'': [=RTS=] [[GameplayAndStorySegregation mechanics aside]], the Scourge is so dreaded across Azeroth precisely because it's mainly comprised of the undead, who require no rest or sustenance, and who can replenish their lost numbers with those they kill.

* ''Manga/DemonSlayerKimetsuNoYaiba'': Demons have infinite stamina, and will endlessly keep regenerating unless they die. This makes a prolonged battle against them to be disadvantageous for the human Demon Slayers, since it's only a matter of time before they get tired and the demon has a {{VictoryByEndurance}}.

* ''Manga/DemonSlayerKimetsuNoYaiba'': Demons have infinite stamina, and will endlessly keep regenerating unless they die. This makes a prolonged battle against them to be disadvantageous for the human Demon Slayers, since it's only a matter of time before they get tired and the demon has a Victory by Endurance.

* The "politician" Vermin Supreme [[https://www.youtube.com/watch?v=4d_FvgQ1csE&=&t=3m34s proposed using zombies]] as a ''power source'' in his 2012 campaign to reduce America's dependency on foreign oil; by placing zombies in a giant turbine and dangling some brains in front of them to make them push the blades, they can become a PerpetualMotionMachine.

* Not "monsters" per se, but ''Literature/{{Discworld}}'' {{Golem}}s just keep going and going and going and going. They're used for menial, tedious labor typically, since they don't have to sleep and, for the most part, enjoy it as much as they can enjoy anything. They even use this as a form of passive-aggressive protest via LiteralGenie; they're smart enough to take initiative and can read the intent behind orders, but if you mistreat them, they're liable to fight back by doing ''exactly'' what you say, constantly, until someone figures it out and tells them to stop. This can mean that the golem you asked to "pump some water" doesn't stop until your shop's street is partly underwater.
** A more traditional version, also a golem, is Mr. Pump in ''Literature/GoingPostal''. As Moist's parole officer, it's explained that even though he can only walk while Moist can run, get a horse, a cart, or even a boat, he will never tire, and never stop until he catches up to him. After one demonstration of this, Moist gives up on trying to run away.
-->You can hide, but you can't run!

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Science savvy characters may [[DiscussedTrope discuss]] how implausible it is that the walking dead in a ZombieApocalypse, despite craving brains, can keep walking 24/7 for years or longer without any kind of sustenance. Compounded by that fact that though decayed they [[SlidingScaleOfUndeadRegeneration never actually rot enough to stop posing a threat.]] Frequently, TheProfessor / MadScientist will fear (or marvel) at [[JustThinkOfThePotential the potential]] these thermodynamic law-breaking monsters represent. This is the whole idea behind undead armies in any setting-- they are weak but fearless and while slow, they can march 24/7 with no supply lines, all while [[TheVirus assimilating the enemies' fallen]].

[[folder:Anime and Manga]]

[[folder:Real life]]