Mech vs. Beast

"To fight monsters, we created monsters of our own."

— Raleigh Becket, Pacific Rim

Oh no, a Kaiju is attacking the city! Bullets are useless, tanks just get stomped, an air strike would cause too much collateral damage... Guess it's time to bring out the Humongous Mecha to punch it in the face.

The idea that it might produce less collateral damage tends to be belied by the buildings smashed by both combatants in their battles. Doesn't really matter though, because watching a giant robot fighting a giant monster is the basic epitome of Cool Versus Awesome.

A Sub-Trope of Flesh Versus Steel and Behemoth Battle. Compare Animal Mecha and Robeast, where it's a combination of a mecha and a beast. See also Ultraman Copy for various giant, (usually) flesh-and-blood superheroes who fight giant monsters, and Primate Versus Reptile, another common matchup in monster stories. While initially very straight forward with the machine being the hero to root for against the beast, invoking much the same visual as a knight in armor against a dragon, in recent years the inverse has become just as common.

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Examples:

Anime & Manga

• The Big O. Several episodes involve battles between the title Humongous Mecha (piloted by Roger the Negotiator) and a giant monster.
  • Episode 3 "Electric City". The Big O must battle a giant monster (known as the Eel) that lives in the lake behind a hydroelectric dam.
  • Subverted in Episode 5 "Bring Back My Ghost". It appears that Big O will have to fight a giant monster that appears in fog by a river, but the monster turns out to be a light illusion projected by a megadeus instead.
  • Subverted in Episode 7 "The Call from The Past". A large aquatic monster called the Sea Titan threatens the fishing industry and it looks like the Big O will have to battle it, but it turns out to be, yes, another false image produced by a megadeus.
  • Episode 8 "Missing Cat". The Big O must defeat a giant genetically engineered monstrosity known as the Chimera.
  • Episode 11 "Daemonseed". A giant tree grows in Paradigm City and starts destroying buildings with its animated roots. The Big O attacks it for a while, but the tree stops growing by itself and doesn't have to be killed.
  • Episode 22 "Hydra". The Big O confronts a gigantic monster known as the Hydra Eel. It appears to be related to the "Eel" monster the Big O fought in Episode 3 "Electric City", but has three heads. Like the Eel, it uses electricity as a weapon.
• DARLING in the FRANXX: Giant robots called FranXX are piloted to fight Klaxosaurs, weird bright blue Kaiju that feed off "magma energy" in cities. The line gets blurred later, when Klaxosaurs turn out to be biomechanical hybrids... and FranXX are essentially a surgically altered Klaxosaur husk.
• Neon Genesis Evangelion: The eponymous EVA mechs are used by NERV to fight Angels, which resemble weird giant aliens with no uniform appearance. The only thing that qualifies them as "Angel" is that they have a "blood pattern blue" (which, despite its name, is still red). However, it's played with because the EVAs are not really robots, but actually cloned Angels in a mechanical restraining bolt. In Episode 7, a competing agency tests an automated nuclear-powered mech, but a malfunction or NERV sabotage causes it to go haywire, necessitating EVA 1 to stop it making it something of an inversion.
• The movie UFO Robo Grendizer, Getter Robo G, Great Mazinger: Kessen! Daikaijuu has these mecha (from different shows) allies to battle a giant prehistoric monster (even bigger than them) surviving unknowingly in the depths of the oceans.

Comic Books

• Primal Warrior Draco Azul: Draco Azul is an ancient alien mecha that was gifted to the Maya civilization millennia ago, and is used to defend Mexico from alien monsters called Diablos.

Films — Live-Action

• Aliens has a fight between a power-loader (basically a Power Armor forklift) and a xenomorph queen.
• The low-budget knock-off of Pacific Rim, Atlantic Rim, naturally features such figths. It's mostly known for getting riffed in season 12 of Mystery Science Theater 3000.
• Avengers: Age of Ultron: Tony Stark in the Hulkbuster armor vs. a mind-controlled Hulk. They may be a bit smaller than other examples but the destruction is devastating all the same.
• Godzilla: The second and third Mechagodzillas were built by the UN to fight Godzilla and similar Kaiju. The first one was a Godzilla impersonator built by aliens. Godzilla Vs Spacegodzilla also had MOGUERA (first introduced in The Mysterians), who helped Godzilla defeat SpaceGodzilla.
  • Godzilla vs. Kong: Mechagodzilla appears as the final antagonist of the film, forcing Godzilla and Kong to team up with one another. In this version, it's a human-built Humongous Mecha that gets possessed by King Ghidorah's consciousness.
• In 2010's Gulliver's Travels, the Liliputian villain builds a steampunk mech a head taller than Jack Black, and strong enough to give him a wedgie.
• King Kong Escapes has King Kong versus Mechani-Kong (who actually predates the more well-known Mechagodzilla by about eight years).
• Pacific Rim is this trope personified. With an entire (defunded) international corps of two-pilot mechs called "Jaegers" for the express purpose of fighting the alien Kaiju coming out of the Pacific ocean.
• Power Rangers: The movies have featured this just like the TV show they are based on.
  • Mighty Morphin Power Rangers: The Movie: The climactic battle is between the Rangers in their new Ninja Megazord against Ivan Ooze who has fused with one of his insect mechs.
  • Turbo: A Power Rangers Movie: The Rangers battle an ancient monster named Maligore in their Turbo Megazord.
  • Power Rangers (2017): After gaining the ability to combine their Zords, the Rangers battle Goldar who in this continuity is a monster created from rocks and gold by Rita.

Gamebooks

• The Fighting Fantasy book Robot Commando allows you to pilot various giant robots, and some fights are against dinosaurs. The cover itself shows one such robot battling a Tyrannosaurus rex.

Literature

• The Grimnoir Chronicles short story "Tokyo Raider" centers around a giant robot created by the Imperium used to defend against a Soviet-summoned demon referred to as the Gorilla Whale.
• The climax of Ready Player One features the main characters turning into Ultraman and MechaGodzilla to battle each other. In the movie adaptation, Ultraman is switched out for The Iron Giant (so instead it's robot versus robot).

Live-Action TV

• The Book of Boba Fett: When the Pyke Syndicate deploys a pair of Scorpenek droids, Boba gets his pet Rancor to fight them.
• The climax of nearly every Super Sentai episode starting with Battle Fever J (and by extension, every Power Rangers episode) involves the Monster of the Week undergoing a Make My Monster Grow and the heroes countering by summoning their Humongous Mecha. Having a climatic battle between a giant robot and giant monster, however, actually originated from Toei's earlier Spider-Man live-action series. Of course, being a Long Runner series, certain Super Sentai series may play on the nature of the mecha and the monsters the heroes fight.
• While many entries in the Ultra Series feature human defense forces battling giant monsters, Ultraman Z plays more into this trope by giving its defense force, STORAGE, several giant robots which they use to battle the monsters. The robots had previously appeared as autonomous mechanical beings in previous entries, but in this series they are piloted mecha.

Music

• The novelty song "Monkey vs. Robot" by James Kochalka of SuperF*ckers fame is Exactly What It Says on the Tin: a song about a monkey (actually an ape in the music video) and a robot fighting.

Tabletop Games

• BattleTech has the potential for this to happen, when BattleMechs come into contact with MegaFauna. It's more often than not an Averted Trope, as of course it's the Mech-on-Mech warfare that most people are interested in. There's actually a planet that uses this trope to attract tourists. Called Hunter's Paradise, it's full of dinosaur-like reptiles that tourists hunt using armed Industrialmechs. Of course, as they're just animals and not super-powered kaiju, there's really not much danger involved.
• Mecha vs. Kaiju, which is Exactly What It Says on the Tin.
• Monsterpocalypse, being a game of giant monster battles, of course has this as some of its factions' kaiju are Humongous Mecha.
• Warhammer 40,000:
  • Knight suits were designed for use in the colonization of planets with hostile native fauna or extreme weather, resulting in a feudal system where nobles wired into giant robots guard their peasant vassals. By the 41st Millennium Imperial Knights are often called to battle Tyranid bioforms or Ork Squiggoths. House Cadmus^note They Who are Not our Allies are our Prey in particular determines leadership in annual hunts of the mutants who replaced their homeworld's extinct megafauna.
  • Practically every faction has truly massive mechs called Titans. The Tyranids, a Swarm of Alien Locusts that uses Organic Technology, have Bio-Titans, immense chitinous monsters meant to go toe-to-toe with mechanical titans and heavily armored bases.
  • The Vorgh, one of the Tau's minor client races, are immense sapient aliens so large that their primary battlefield role is to wrestle down enemy armored walkers.

Video Games

• Cosmic Star Heroine has a playable battle that works like this. After the party has defeated a giant mecha all on their own, its pilot, as a last-ditch move, releases an artificial creature named the Blobmith which grows to kaiju proportions in seconds. Alyssa, the titular heroine, then knocks the pilot out, takes control of the mecha and uses it to battle the Blobmith, before activating the self-destruction sequence of the mecha and blowing both it and the monster up. It's all a Big-Lipped Alligator Moment because it has no impact on the rest of the plot and nothing to do with anything else, but it sure looks cool.
• In Earth Defense Force 5 the 150 foot Baraga, a mech built to function as a construction crane, is utilized as a weapon of war to defeat a large group of Archelus and Erginus.
• In Fortnite, the Battle Royale Season 9 live event featured the giant Mecha Team Leader battling against a giant beast known as Cattus, or more officially, the Devourer. An epic battle ensued in real time, with the Mecha emerging victorious after stabbing the Devourer's head with a giant sword made from the statue of Singularity.
• Into the Breach is a Turn-Based Tactics game in which you control a mech squad to repel the invasion of kaiju known as the Vek.
• The sequel of King of the Monsters replaced the King Kong Copy character Woo for his Mecha counterpart called Cyber Woo, which became so famous that it received an appearance in NeoGeo Battle Coliseum in a human-like size, being controlled by a Child Prodigy.
• Inverted in Mass Effect 3 when Kalros, the semi-mythical mother of all thresher maws, is summoned to fight a Reaper Destroyer.
• Robot Alchemic Drive has this as the entire plot with alien robots from space coming to earth on a semi-regular basis and the player having to fight them with remotely-piloted giant mecha.

Web Animation

• Episode 27 of Super Power Beat Down features "Godzilla vs. Dragonzord". The King of the Monsters versus one of the most powerful Power Rangers Zords.

Webcomics

• Tuesday Titans: A rare case where the Titan "beasts" are the heroes and the Severine "mechs" are the villains.
• Unsounded: Cresce developed their giant humanoid Firelopers to fight Alderode's dragon-like giant Vliegeng.
• The Whiteboard: After Jinx is temporarily mutated into a twelve-foot rampaging monster, Kasi jumps into one of Doc's Powered Armor suits.

Websites

• Neopets: Resident Godzilla parody Chiazilla has a Mechagodzilla equivalent in the form of Dr. Sloth-created Mechachiazilla. The battle between them was a major plot point in 2000's Hunt for the Battledome.

Western Animation

• Futurama:
  • "Anthology of Interest I": A giant Bender is attacking the city, so Professor Farnsworth enlarges Zoidberg to fight it.
    Hermes: We're jerked! Nothing can stop a monster that big!
    Prof. Farnsworth: Nothing except an even more equally big monster!
  • "Benderama": Bender combines with his nanoreplicants to form one giant Bender to fight an alien giant.
• LEGO Jurassic World: The Legend of Isla Nublar: Danny Neidermeyer does battle with an Allosaurus and a T. rex with a dinosaur mech that he intended to use for digging up No Beard's treasure.
• One of Terry Gilliam's Monty Python animations was about an invasion of killer cars that were defeated by atomically-mutated giant cats. Unfortunately the cats then ate the city.
• Sym-Bionic Titan: The eponymous mech versus the villain's Monster of the Week, although near the end of the first (and only) season, the American military did eventually build a mech of their own which managed to take down a Kaiju.

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