Tetsujin #28, or Gigantor as it was originally known in North America, was probably the first "giant robot" anime imported to the United States. This black-and-white series was aired during the 1960s in many markets.
Go Nagai's Mazinger Z was the first series to feature giant robots piloted by humans, the convention which came to define the entire genre. It also created the Super Robot Genre as we know it, featuring, if not originating, many of the tropes that have come to be associated with the genre. The series, along with sequels Great Mazinger and UFO Robo Grendizer, have been aired worldwide.
The caption for the page image is in fact a good example of Hilarious in Hindsight. Go Nagai, trying to come up with an idea for a giant robot story that wouldn't rip off Tetsujin, was observing a gridlock one day when he mused to himself that the drivers in back must be wishing for a way to bypass those in front. From that idle thought came the concept of a man-driven robot, and the rest is history.
Getter Robo, the first Transforming Mecha and Combining Mecha, which also features some of the most humongous mecha in the medium. The mecha progressively increase in size and ridiculousness over the series, ending with the Getter Emperor which stands over a freakin' galaxy.
On the other hand Freeder Bug, also created by the late Ken Ishikawa has some of the least humongous Humongous Mecha in anime or manga, not counting power suits. They're essentially just heads with stumpy limbs and a chair fixed to the back, and are smaller than an adult man.
Robotics;Notes is a very unique reconstruction. While the opening features many mechas that look like they belong in a Super Robot Genre anime, the series focuses on a club of students living Twenty Minutes into the Future as they work together to build a Humongous Mecha of their own. Aside from the comic relief moments and the Otaku shut-in, the characters don't feel like mecha anime characters, but ordinary people. The anime also feels much more like a Slice of Life. However, this being by the same people who brought us Steins;Gate, a darker conspiracy soon comes to light and our group of protagonists are pulled into the mix when it becomes clear that the world's leader in robotics is planning on causing a global disaster and wiping out more than half of the human race. Now it's up to them to quickly complete their mecha and save the world.
In Gundam Wing, a bit of Justified Trope goes on for the humongous mechas in the series where Lt. Noin explains that the advent of the mechas came about when the Alliance wanted a physically intimidating weapon.
Technically, both Transforming Mecha and Combining Mecha have been in most Gundam shows. Gundam, ZZ Gundam, V Gundam, V2 Gundam and Impulse Gundam all use the same principle, with being module based and all. Freedom and Justice can both combine with the METEOR Units, and Exia and Dynames both have the GN-Arms Type-E and Type-D respectively. 00 Gundam also had the 0 Raiser and Arios had the GN Archer. In the Gundam 00 Movie, the large backpack on Raphael Gundam turned out to be an upgraded Seravee Gundam, transformed into a giant weapons-platform.
As for Variable Mobile Suits, the Z Gundam, ZZ Gundam, Methuss, Re-ZEL, Re-GZ, and a lot other UC Suits qualify. Also, the Wing Gundam, Wing Gundam Zero, Airmaster, Airmaster Burst (the latter two from Gundam X), Aegis, Murasame and Savior (from Cosmic Era (SEED and SEED Destiny)). And Kyrios/Arios/Harute and Gadelaza, Regnant, Empruss, GN Archer, Flag (and variants) Enacts, Hellions, Realdos and Reborns Gundam/Reborns Cannon are all Variable Mobile Suits from 00. And there are probably some that were left out.
Super Dimension Fortress Macross features some of the earliest transforming mecha, with the Valkyrie jet/space fighters that could turn into humanoid robots and a hybrid semihumanoid/semijet ("gerwalk") form. The Macross itself was a huge spaceship that could rearrange itself into a pointlessly humanoid configuration.
When SDF-1 performed Hypespace Fold at the beginning of the show, its fold drive mysteriously disappeared along with a chunk of other machinery and major powerlines. So, the whole point of Modular Transformation was to reconnect Macross Canon to the power supply.
This, however, was completely ignored in the following series on the same universe, and "Macross" type spaceships always have to transform into some pointless humanoid form to fire their main gun. Rule of Cool all the way.
Macross Frontier doesn't always follow this, however. Both the Macross Quarter and Battle Frontier are seen firing their primary weapons while in "ship" mode.
The humanoid configuration also allows the capital ships to use the MacrossAttack without compromising the firepower, safety, or maneuverability of the entire ship.
Another mech that's particularly iconic to the series is the Destroid Monster, which has an appearance and speed that wouldn't look out of place in BattleTech.
Which itself can be considered as not looking out of place because in the early pre-1995 versions of Battletech, various mecha there were licensednote incorrectly; it's a long story from anime, including Macross.
Worth noting that the Humongous Mecha built in this series were specifically built because the Zentraedi they were fighting were giants; the Valkyries and Destroids were built so that humans could fight them on an even playing field. Of course, the Zentraedi have Humongous Mecha of their own, which tower over the human mecha at nearly twice the size.
Giant Robo is a descendant of a 1960s live-action series brought to the U.S. as Johnny Sokko and His Flying Robot.
In 20th Century Boys. The Big Bad, Friend, holds a robotics engineer hostage so that he can construct a fifty-foot giant mecha to use on the Bloody New Year's Eve. However, throughout the brainstorming process, the aforementioned engineer is on the verge of snapping because he can't get them to understand that a robot constructed in such a way probably couldn't even stand, much less cause massive havoc and destruction. They eventually make a cheap, pretend mecha that just looks like a humongous mecha instead. Not that everyone else realises this, though...
Nevertheless, the final arc plays this straight when said robotics expert finally succeeds in making a working one. It's kind of justified in that by then it's been about 20 years since the first time.
Gasaraki attempts (amidst an incomprehensible mass of mysticism) to show a "realistic" view of giant war robots in a contemporary setting. The "Tactical Armors" of Gasaraki are not much larger than a main battle tank, require extensive support squads, and can have their joints fouled by blowing sand.
Infinite Ryvius have the characters burst into laughter when they first saw a giant humanoid robot because it seemed so impractical. Needless to say, they were proven wrong.
Full Metal Panic!, like Gasaraki, attempts to show "realistic" robots in a "modern" setting, but is considerably more relaxed about what constitutes "realistic", and much lighter-hearted. It also acknowledges that man-shaped robotic fighting machines are at the very least unlikely, but promptly handwaves the objection away with a mysterious source of ultra-advanced technology.
If we forget about the question how they actually work, their combat efficiency is not shown as overwhelming (unless using even more ultra-high tech), unlike most examples. In the first episode of the anime taking out Hind helicopter is seen as a show of great mastery, and later, a single tank is designated by AS on-board AI as a serious threat.
In Neon Genesis Evangelion the titular Evas are biological robots in the form of cloned Eldritch Abomination humanoid beings plated in restraining armor and having their spine and nervous system fitted with cockpit housing units. This is important because the Entry Plugs, designed to mentally and physically synchronize the pilot with the Eva in conjuction with LCL, will vary in effectiveness depending on their depth and the pilot's psyche, to the point that going Up to Eleven can and will result in the synchronization transcending metaphysical levels.
Eureka Seven also uses mecha similiar to Evangelion, where the mecha are more than simple robots. The LFO and KLF units, as they are called, have a form of sky surfing applied to their operation. Additionally, the units are Transforming Mecha, as most can change into land vehicles.
The immensely popular Martian Successor Nadesico not only features a battle mecha class called the "Aestivalis", but also incorporates a 1970s-style Super Robot Genre anime called Gekiganger 3 as a Show Within a Show. "G3" is a clear homage to the early classic Getter Robo, and manages to hit all the classic melodramatic cliches of the genre.
The popular Japanese franchise Sakura Taisen employs not-so-Humongous mecha (only about 10-12 feet tall), powered entirely by steam (and empowered by the pilots' psychospiritual ability, or "reiryoku"). The mecha fight demons and evil spirits who, in turn, pilot their own appropriately evil steam-powered robots. The franchise's mecha are entirely super, though, with a whole list of named super-moves and various highly improbable weapons, including a revolver, gun-barrel sword, and giant psychically animated teddy bears.
Patlabor is likely the most feasible Humongous Mecha anime, featuring short, non-combat robots used for civilian purposes such as construction. The only combat robots belong to the protagonists, the police, who prevent mecha-related crimes and the military, like the Japanese Self-Defense Force.
Soukou No Strain, which, though it may not be what it seems, is certainly about mecha pilots.
Utawarerumono has a nation composed of a religious minority who have giant mecha given to them by their god to defend themselves. Considering the rest of the world hasn't even invented gunpowder, this is probably overkill. Then again, their god is a psychotic nihilist.
Tenchi Muyo!! GXP: the main character Seina, already the captain of his own ship, finds a giant mecha in a late episode, and after using it to trash a few pirate landcruisers, decides, "Ships are great and all, but real men need giant robots!" His giant robot also looks suspiciously similar to one from another anime from the same creator.
The leaders of the Nobuseri bandits in Samurai 7 are massive cyborgs, with swords the size of houses.
Tengen Toppa Gurren Lagann takes the "humongous" part to ridiculous extremes, with each incarnation of the main mecha being piloted by the smaller mecha. The show starts with the Mini-Mecha, Lagann, which was discovered by Simon. After Kamina hijacks an enemy mecha, which he names Gurren, he combines it with Simon's Lagann to form the regular sized (by mecha standards) Gurren Lagann. Simon uses Lagann to capture Thymilph's Dai-Gunzan, an enormous mecha/warship, which is renamed Dai-Gurren and serves as the base of Team Dai-Gurren. After the Time Skip, Team Dai-Gurren acquires the Arc Gurren Lagann, which is about the size of a city. Then the moon turns out to be a huge starship which is transformed into the appropriately moon-sized Super Galaxy Gurren-Lagann. Finally, in the Final Battle, Simon and the Team Dai-Gurren combine their Spiral Power to manifest the Tengen Toppa Gurren Lagann, which is confirmed to be ten million light years in height. The second movie, Lagann-hen, does takes it to the next level, but the Super Tengen Toppa Gurren Lagann is more of an Energy Being - a humanoid figure made out of Spiral Energy flames, with Kamina's cape and Simon's Cool Shades which are actually the Tengen Toppa Gurren Lagann floating in the middle of the Super TTGL's face. In other words, if you like humongous mecha, this is porn for you.
GunBuster and its sequel DieBuster have Mecha even more Humongous than most- Gunbuster is two-hundred fifty-meter-tall, and Diebuster is approximately the same height as the Earth itself.
Probably worth noting that Gunbuster and Diebuster were made by the same studio as Gurren Lagann. In fact the Tengen Toppa Gurren Lagann was probably partly to upstage the Diebuster, which in turn upstaged every other Humongous Mecha that came before (except those from Demonbane prequel novelnote released in 2003, a year before Diebuster, that is).
The Xephon from RahXephon, although obviously and definitely not mechanical, follows many of the genre's tropes to a T.
The Rune Gods/Mashin in Magic Knight Rayearth take form of not just beastly creatures, but also Humongous Mecha based on those said creatures. The second half introduces a faction that uses regular mechanical mecha, too.
All of the Humongous Mecha that Team Rocket wields in the Pokémon anime. One has to wonder where they get the money for all those giant robots, considering that they're both deep in debt and far out of favor with their boss...
In one episode in the Diamond and Pearl series, it was noted that Team Rocket stole various parts from a factory, which they used to build that episode's mecha. That seems to help keep their expenses down.
They also occasionally mention buying cheaper "build-it-yourself" mechas online, especially in the Johto story arc. That's one explanation for why most of the mechas have at least one glaring weakness.
Played with in an episode of Wolf's Rain in which the wolves accidentally reawaken an ancient defensive mecha while making their way through a ruined city.
The main villains in Scrapped Princess are capable of transforming into Humongous Mecha. They are forced to use power limiters to maintain a normal human guise until they are authorized to carry out their mission.
Mecha are part of the central conflict in Code Geass. A one-sided war was won with them, and now they're being used to reclaim the country from The Empire. And in a case of Fridge Brilliance, dodges the whole too-vulnerable-to-having-it's-legs-shot issue by adding landspinners, making the mechas too friggin' fast to target their legs accurately. Or in the case of the Lancelot, target the whole mecha accurately.
Though most of them are Mini-Mecha, each only being a few meters tall. The truly humongous mecha are Knight Giga Fortresses like Siegfried (which is really the only one) which is 5 times as tall as most mecha in the series, and 8 times as heavy, but is less a robot, and more a flying spiked ball. Gawain is the largest true Knightmare Frame, but is only 6.5 meters tall, when most Knightmares are 4 to 5 meters.
The Galahad unit used by the Knight of One is 9.5 meters tall and so heavy it's sword sheath needs its own rocket booster. it also wields a BFS about as large as itself.
In Gad Guard, the mecha aren't piloted, per se. Rather, the person they "belong to" rides around on their shoulder, or some such. While some of them occasionally give their mechs orders (especially the villain), they tend to act on their own. In battle at least...
The "Endlaves" from Guilty Crown are a more realistic example than most - most prominently, rather than actually being piloted by human beings they are remote controlled via a virtual reality interface by operators that might be sitting kilometers away in a bunker (or just on the edge of the battlefield, in an armored van). They are generally not very tall (with the largest ones appearing no more than 9-10 meters, and most looking around 4), and travel over long distances in a vehicle-like fashion using wheels while keeping close to the ground and hard to target. It's also worth noting that they don't appear to be actual military weapons, but rather, tools of law enforcement/riot control (which goes a great deal to explain giving them a humanoid form in the first place).
The Armor Troopers from VOTOMS (Verticle One Man Tank for Offense and Maneuvers) are perhaps among the most perceivable (combat based) humongous mecha in real life. They are no taller than 4 meters, do not transform, don't fly, and generally don't have any unique powers. They are more like bipedal tanks than anything else.
See also many of the other series created by Ryosuke Takahashi, such as Dougram and SPT Layzner. While they're not as realistic as VOTOMS, they are compared to the majority of mecha shows and have a similar gritty atmosphere.
The protagonist builds an AT from scrap parts several times over the course of the show. They're repeatedly shown as disposable and cheap.
Geneshaft has a very weird mecha, which looks more like a set of cranes welded together to vaguely resemble a human outline. It is also unclear why it should look remotely human anyway, given its function in the story.
Funnily enough, Saber Marionette J parodies this when the Imperial Palace eventually transforms into a Giant Robot, who is then used to attack and stop a Giant Bomb.
The Brave Series franchise is a series of mecha shows each starring a different Super Robot and their respective crews. They will often feature a pair of main characters, rather than a single one (usually a young boy and a grown man, who often serves as a big brother feature). By far the most famous of these is The King of Braves GaoGaiGar, a series which managed to recapture the feel of fun and Hot bloodedness of mecha from the 70's amidst a wave of Darker and Edgier mecha series in the wake of Evangelion. Also had a sequel OVA a few years later which managed to be of better quality (especially the fight scenes!) than most series of its kind. That proved so popular it got a special edition just 5 years later, linking it to Betterman, a much different kind of mecha show from the same company. Also, had a brief Follow the Leader series, Brave Police J-Decker, which featured sentinent, non-piloted robots a la Transformers.
Each of the different nationality random girls in Rizelmine has one, each almost more ridiculous than the last.
The mecha in Irresponsible Captain Tylor seem to be specifically designed to subvert the "Humongous" part of this trope, in fact most of their pilots are huge and shown to be very cramped inside their mecha. The big butch leader is in a pink one. The general design of the mecha is similar to the squat egg-shaped ones found in Sakura Wars.
(Much) Later on, Haruna uses her artifact to create a life-size robot body for Sayo. Sayo can only use the robot body by possessing a small voodoo doll and climbing inside the robot body and piloting it Humongous Mecha style.
Zoids manages to buck the trend in giant robots by having its eponymous robots patterned after nearly every animal imaginable except humans. This ranges from tractors shaped like beatles to flying battleships that look like whales. A recurring theme through the various editions of the franchise is that the hero tends to pilot a Zoid based on a large feline (usually called a "Liger"), while his rival pilots a robotic dinosaur.
Its Spin-Off series Soukou Kyoshin Z-Knight feature humanoid mecha developed from zoids. The six Armored Titans, including the titular Z-Knight, are even powered by zoid core.
In Project A-Ko B-Ko creates these although she is perhaps better known for her Bikini Battlesuit.
Busou Renkin has an example in the form of Great Warrior Chief Shosei Sakaguchi's Busou Renkin, Buster Baron, which resembles a 57m knight armed with a pair of knuckle dusters and a jet pack and is capable of using giant forms of the Busou Renkin of alchemy warriors who are riding in it.
The eponymous Escaflowne is a 20-something-foot-tall Magitek mecha that can transform into a dragon-mech.
In a MÄR Filler arc, a trio of sisters can summon their mecha 'Rotkappchen Waltzer'.
Those with ghost ARMs can themselves be considered human-sized mecha as well, as they combine with the person.
The Atlas-class ship Deucalion (Mecha Form) in Kiddy Grade. Just watch the last 4 episodes (and mind the statistic of the Deucalion) then you'll understand why (one of its design goals being to steal the Earth).
6358 fucking kilometers in length. You can't go wrong with that.
Eita Touga of 12 Beast has some of these in his army, piloted by small, adorable golem girls.
Space Runaway Ideon features unusually large mecha for its time, with the Ideon being 105 meters tall. While the most numerous Mooks, Adigo, are 48 meters tall when standing straight, and considered as small class mecha, most of the Elite Mooks are taller than Ideon.
Suisei no Gargantia opens with high tech mecha battles in space but quickly switches to an After the End water world Earth where the mecha are more along the lines of highly advanced forklift-truck/submarine mash ups in vaguely humanoid form. The more advanced mecha - Chamber - actually has a highly developed A.I. and 'he' can make his own conjectures and decipher scenarios faster than his pilot Ledo usually can; making him very close to sentience almost certainly making the leap to self awareness by the last episode.
Galilei Donna has them. Kind of overshadowed by the fish-themed airships, though.
The "Ikusa Yoroi" ("War Armors") in Nobunaga The Fool; their designs seem to range from Midieval knights (like in Escaflowne), to samurai (fitting, given the setting of the Western and Eastern Planets).
Predating Patlabor, most mecha in Combat Mecha Xabungle, with exception of few models (like the Xabungle), are actually working machines used for digging mineral. However, the savage Wild West-ish setting means pretty much every mech is also armed with a weapon.
X-Men has the Sentinels, mutant-hunting Humongous Mecha. They started out small (when compared to Evangelion, Super Sentai, etc.) but worked their way up to standard mecha size. Much worse (in terms of design impracticality) is that they were created in a "Master Mold," which is actually a much larger Sentinel. There is no good reason for a factory to take this shape. Since A.I. Is a Crapshoot, Sentinels are known for getting out of their creators' hands in short order (Especially Master Molds, Sentinel-shaped factories which wouldn't need any decision-making ability.) The Literal-MindedAIs in fact point out their creators' fallacies - "Hunt mutants? You do know that there are some mutations in every life form? Humans are mutants."
First Comics' Dynamo Joe? (Sometimes scripted by Phil Foglio.)
The BGY-11 of The Big Guy and Rusty the Boy Robot is secretly a humongous mecha; the world at large and Rusty in particular assume that it is a sentient robot, and maintaining this secret complicates several episodes.
Back when Marvel had licensed Godzilla as a character, they also created the Red Ronin giant robot to fight him. Godzilla has faded away from the Marvel Universe, but the Red Ronin still shows up. Occasionally.
In Earth X, Tony Stark has secretly redesigned the Red Ronin into a Transforming Mecha that spends most of its time as his "Iron Avenger" factory. We don't know this till the end of the story (making Tony appear to be a useless recluse), when he pilots it into battle against the even larger Celestials, who are energy being versions of the same—their energy bodies need Humongous Mecha to give them shape.
Iron Man also built one to fight Megatron in a crossover between the Avengers and Transformers. He also has his various designs of the Hulkbuster armor which approach this trope and War Machine's satellite turns into this trope.
The Godkiller, a mecha designed by a race called the Aspirants to fight the Celestials, is almost five miles tall.
Kazu Kibuishi's Amuletfeatures a house which sprouts arms and legs and starts walking.
Warren Ellis' Tokyo Storm Warning.
The Man-Robots from the Disney Comics story "The Giant Robot Robbers" by Carl Barks.
Jack Hawksmoor of The Authority can actually turn cities into Humongous Mecha. As in, walk into the middle of Tokyo, ask it very nicely, and come out wearing battle armour made of concrete and skyscrapers.
The Guardians in Gear. Nothing quite like mecha being piloted by anthropmorphic cats who look like they could have easily been extras on Steamboat Willie
In the Crapsack World of the Kingdom Come series, an aged Batman fielding an army of computerized mecha is the reason why Gotham City, along with The Flash's Keystone City (constantly patrolled by the Flash at ultraspeed), is one of the only safe places for a normal human to live.
Though rare, giant robots do show up on occasion in Judge Dredd. The majority are from Hondo City, appropriately enough.
Whether S.T.R.I.P.E. is a Humongous Mecha or a suit of Powered Armor depends on the writer and the situation, although it started out as a Humongous Mecha in the Stars and Stripe series.
In the Crapsack World of Give Me Liberty, the "Fat Boy" fast-food chain uses a humongous mecha mascot in their war to raze the Amazon rainforest into farmland.
In Transmetropolitan, The City has numerous humongous disabled mechas reminiscent of Evangelions called Gladiators that stand their ground scattered all about, towering over the landscape. They are at least 200 years old and there was no record of these being ever used. Spider Jerusalem remarks that their steel penises fell off thirty years before, killing numerous civilians.
The monstrous heroes of Monsters vs. Aliens face villain Gallaxhar's enormous Robot Probe. The Probe withstands a military strike and destroys half of San Francisco in its conflict with the monsters before being destroyed by Ginormica. It's later revealed that Gallaxhar has an army of Robot Probes at his command, but when he orders them to destroy Ginormica, they end up smashing into each other like dominoes.
The Incredibles: The bad guy makes giant robots to destroy all the Supers, improving his design each time a super manages to destroy one.
The Matrix Revolutions: Humanity fights off a flood of enemy machines with 20' tall humanoid mecha. The pilots are almost completely exposed in the suits, making them pretty worthless once the machines get close. Word of God explains that the machines tore through armor like butter, meaning there was no point it keeping it there if it was just going to be useless anyway.
Robot Jox was a low budget western attempt to exploit this genre. In a dystopic future, wars are resolved by duels between two giant mecha, much like a sporting event.
A rare, non-humanoid example: in the 2005 version of The War of the Worlds, it's revealed that the aliens piloting the giant tripods look like human-sized versions of their death machines, making them the extraterrestrial equivalent of humongous mecha.
Deconstructed by a simulated Humongous Mecha battle that takes place between two diplomats in the Dream Park novel The Barsoom Project. Their battle is staged in the middle of a simulated city, complete with tiny terrified civilians who die in droves every time the robots make a move, as a psychological ploy to get the bickering diplomats back to the negotiating table.
Later installments of the franchise (from Kyoryu Sentai Zyuranger onwards) would be adapted into Power Rangers, which terms all its mechas as "Zords" and the combined forms "Megazords", with "Ultrazord" occasionally used when their entire arsenal combines.
The absolute biggest would have to be Daijinryu/Serpentera. To make it clear: Dairenoh/Thunder Megazord is 54 meters tall, Daimugen/Tor the Shuttlezord is 95 meters, and the Brachiosaurus/Brachiozord (the tallest in the franchise to be controlled by a Ranger) is 112 meters. Daijinryu/Serpentera is 500 meters long and 345 meters tall when standing.
To make it clearer, we once got a distant shot of Serpentera standing in the city, and buildings were about the size of one claw. In its shadow, day becomes night. If it were to lie down, its head could be downtown and its tail could be in a suburb. In franchise history, its size has yet to be topped. (That's probably bigger than 500 meters, but when it's All There in the Manual stats versus the Rule of Cool, cool wins out.) This led to an infamous case of Your Size May Vary in "Forever Red".
If anything, its counterpart, Xenon, was the jigsaw. Vitor folded about 8 billion different ways depending on whether you wanted it in jet form, Xenon form, or Synchro (Servo combination) form. Borr, the Drill Tank, split into 4 different parts to make Synchro's shoulders/fists, and to change Tracto from Xenon's legs to Synchro's you had to turn it inside-out. Adding insult to injury was the fact that not only that did its Xenon form hate staying together, but that it looked like a really lousy Optimus Prime knock-off.
Parodied in the Beastie Boys' "Intergalactic" video.
The video for Jason Forrest's 'War Photographer' features a pair of humongous mecha. That transform out of giant robots. Crewed by vikings. Who battle it out with the power of rock and roll. No, seriously. And you know what? It's awesome.
Aerosmith has own fight with giant robots and fanservice in videoclip of Fly Away From Here.
Linkin Park's video for "Pts.OF.Ahrty" features CGI Humongous Mecha, each of which is based on the band members. So if the trope wasn't Awesome, but Impractical enough already, you have one that's as skinny as the lead singer.
The pinball conversion kit Gamatron depictes one of these attacking a lunar base.
The classic western Humongous Mecha tabletop game is BattleTech, and its RPG spinoff, MechWarrior. Both series feature everything from 3-meter tall battle frames to hulking 25-meter tall Humongous Mecha, and had Transforming Mecha before their botched design licensing contract fell through with Harmony Gold. Originally created by FASA Corporation in 1984, it was sold to Wiz Kids in 2000, and has been owned since 2003 by Topps.
Also, high-Essence Alchemical Exalts...until they turn into cities.
Also also Hellstriders. They're made of demons.
Every race in Warhammer 40,000 has at least one type of giant mech, though the Tyranids' uses Organic Technology; the sizes grow from Space Marine Dreadnoughts and Tau Battlesuits about thrice as tall as a man to at least 150 meter tall (the accounts contradict each other; some claim the heights go all the way up to 2km) Emperor-class Titans mounting cathedrals, housing a full company of troops in their legs and able to pull ground-to-orbit duty against enemy spaceships. It is said there are mechs large and powerful enough to metaphorically mop the floor with even Emperor-class Titans. The Apocalypse-class.
It's been said that an Emperor Titan, built to scale with the actual Space Marine figures, would be the size of a 10-year-old. Anything large enough to take down an Emperor is probably large enough that if a model was ever made, with a bit of work with power tools you could wear it to a tournament.
The Imperial Guard has specialist tanks designed for anti-Titan work. Shadowswords are armed with a Volcano cannon, which is itself a Titan gun. Titans are somewhat less impressive when a tank on the ground vaporises one of its knee joints...
Even Dungeons & Dragons gets in on the act with the Eberron campaign setting. The warforged are a playable race. Their "ancestors"—or more accurately, prototypes—called warforged titans, are not.
Some golems can get pretty humongous, as well, in particular the iron, mithral, and adamantine golems. However, the biggest autonomous constructs are undoubtedly the colossi, 100-foot tall humanoids of stitched flesh, hewn stone, or cast iron, only ever created by the mightiest wizards.
Dating back the the first edition Dungeon Master's Guide is the Mighty Servant of Leuk-o, something of a giant mecha which is controlled from a cockpit containing something like one hundred unlabelled levers, each with a different function.
Also in old D&D, an obscure module called "Earthshaker", which was set in and around a gigantic gnome-crewed robot.
D&D's sister product, d20 Modern goes for the direct route. The magazine supplement Mecha Crusade puts forth options for mecha that go from large Powered Armor all the way to true Humongous Mecha (or, in game parlance, "Colossal Mecha"). These rules were later touched up slightly (the highlight being conversion to D20 Modern's built-in economy instead of the clumsy level-based Point Buy System used by Mecha Crusade) and included as a chapter of D20 Future.
Heavy Gear, which features smaller robots than BattleTech's average, but which are definitely more than just body armor.
Rifts features a wide variety, from the Triax Devistator which can step on things up to the size of a two-story house, to designs such as the Ultimax and Terror Trooper which stand about twice the height of a man and blur the line between powered armor and mecha.
And the famous Glitterboy, which is fairly small for a mecha but has to use built-in drills to secure itself to bedrock in order to not fall over from firing its ground-to-orbit "Boom Gun" railgun.
GURPS Mecha gives players the wherewithal to design and build every example on this page and then some. Some finds that doing this results in a quite startling mix of Tech Levels for any but the simplest battlesuit (GURPS Mecha defines a "battlesuit" as powered armour where the pilot's arms and legs extend into the suit's arms and legs. A "mecha" is piloted from a cockpit. So the Iron Man armour is a battlesuit, while an AT-AT is a mecha).
The Pyramid Magazine adventure for GURPS Discworld "A Little Job For The Patrician" features a Discworld Mecha. Based on a design by Leonard of Quirm, adapted by a brilliant Agatean nobleman whose narrative causality tends towards anime tropes, and powered by five trolls. The trolls even go through an Invocation as the thing assembles ("Other leg troll, put it together!"), although since they're trolls in a warm climate, it's possible they'd forget which one went where otherwise.
The mix of Tech Levels makes sense. Steel (TL 3) is still quite common as a building material today (TL 8).
GURPS Magic Items 3 includes rules for "mechagolems", and a brief sketch of a setting where The Fair Folk use these in ritual battle with one another.
Mekton is a tabletop RPG that is meant to run any humongous mecha. Admittedly, there is no size scale for something on par with the Tengen Toppa Gurren Lagann, but still...
Ahem. Excessive scale. Page 113.
The scaling system in Mekton Plus is used to build five main scales of vehicle (of any kind): 1/10 (human), 1/5 (roadstriker - motorbikes and cars), 1/1 (Imperial Guard tanks, Gurren Lagann, most Transformers), 10/1 (really big combiners, mecha that turn into buildings for concealment, Dai-Gurren, Imperial Titans, the Millennium Falcon), and 100/1 (the Space Battleship Yamato, the Transformer Metroplex, Arc Gurren-Lagann). There are rules to expand this scaling system to take care of "mecha bloat", so you might use a 1000/1 or 10000/1 scale to build a moon-sized structure like the Cathedral Terra or Unicron, or a 1/100 scale to build Rock 'Em Sock 'Em Robots. Excessive Scale is reserved for the really, really unbelievably big things...as written, it would be used for Unicron and up, but for a TTGL-style game, it's probably best to reserve it for light-year scaling. You can invest in huge amounts of Expanding Plasma to turn your Optimus Prime figure into a galaxy-sized war engine.
The Mutants & Masterminds supplement Mecha & Manga has a chapter devoted to creating your own Humongous Mecha.
The satirical game Macho Women With Guns had an enemy called BattleWarMechBots. It lampshades how ridiculous the whole concept is militarily, physically, and technically, noting that they were abandoned in favor of good old tanks once everybody realized that they just don't work.
The Iron Kingdoms game WARMACHINE is overflowing with (artifically-intelligent, rather than piloted) mecha, though most only qualify as Mini-Mecha. The Colossals, however, fit this trope quite well; the models are mounted on bases the size of a CD, in game where a human is 30mm tall. Unusually, the setting actually brings up the issue of the inefficiency of Humongous Mecha: The Colossals were the first warjacks to be created, but were abandoned for more efficient designs after the Orgoth were overthrown. The current Colossals are a recent development, with a whole book dedicated to their release.
During his exile on Bara Magna, Mata Nui has found an older giant robot of nearly the same type, an early prototype for his former body, which the inhabitants had used as a shelter without knowing what it was. Mata Nui retrieved its power source, reassembled it, and activated and inhabited it to confront the approaching Makuta. It kinda didn't work.
The Great Spirit robot actually carried two about human-sized pilots in its control center, placed there in case the robot malfunctioned or if Mata Nui lost control over his own body. Unfortunately, they died during the Great Cataclysm, which was caused by Mata Nui falling into coma and crash-landing on a planet. Beyond this tidbit, though, the fact that he had manual controls never came up in the story.
Kotobukiya's Frame Arms. The background story provide that the Frame Architect was originally suppose to be labor machine in grand scheme known as Project Re Sphere. After 10 years of trial and error, they finally get Frame Architect 001 which can mimic human movement perfectly and can use in all environment by swapping parts. Unfortunely, Project Re Sphere doesn't get launch and Frame Architect instead got turn into weapon known as Frame Arms by various nations.
Hero Factory appears to be exploring this territory now. Finalized pictures of the Winter 2014 wave feature smaller-scale versions of the characters piloting mecha to battle huge subterranean monsters.
Has been a central goal for the Golems userbase ever since the original release.
The MechWarrior video game franchise is based on the Battletech/Mechwarrior pen&paper/miniatures universe.
The original MechWarrior game takes place at the end of the Third Succession War.
MechWarrior 2, MechWarrior 2 Ghost Bear's Legacy, and MechWarrior 2 Mercenaries deal with the events immediately before, during and immediately after the Clan Invasion of the Inner Sphere.
MechWarrior Living Legends, a total-conversion fan-made Game Mod for Crysis Wars. Multiplayer only.
The Heavy Gear video games are based on a Pen & paper game universe published by Dream Pod 9. Heavy Gear and Heavy Gear 2, published by Activision in 1997 and 1999, were developed after Activision lost the rights to the MechWarrior series. Heavy Gear primaraly features powered armor, which called "Gears" in-universe, but it also features larger mechs, called "Striders."
Xenogears and Xenosaga? Humongous Mecha for days. In some cases, there are battles against giant foes where the characters have to enter said mecha, or get stepped on.
Xenogears has the Super Dimensional Gear Yggdrasil IV. if the name wasn't a send up enough as it was, the fact that it transforms from battleship mode to humanoid mode makes the Macross homage even more obvious.
There seems to be something of an arms race near the end of the game as to which side can bring out an even bigger giant robot that, for whatever reason, they didn't bring out sooner to an extreme advantage. Eventually, we get to SDGY 4 and Fort Hurricane, each of which is the size of large cities.
In Xenosaga, the Erde Keiser sidequest is a send-up of the more light-hearted Mecha shows (in a game that's more dark and serious). And a send-up the G-Elements in the predecessor, Xenogears.
Xenoblade continues the tradition. There's a god who fits the trope. The setting of the game takes place on the two gods, so it constitutes for roughly half of the game's landmass.
The Steel Kossack from early PSX video game Krazy Ivan. As the trope description says, it approaches the line between Power Armor and this trope; the eponymous Ivan controls it by doing the actual movements himself. This one falls straight into this trope, however, as the Mecha is far larger than a human.
Live A Live gives us Buriki Daioh, a giant ancient Babylonian giant robot. It appears in the Near Future chapter expressly for the purpose of stomping tanks, shooting lasers at airplanes, shooting missiles at larger airplane aircraft carriers, and punching an animated bird statue that is threatening to devour the world in a wave of liquefied human hate. (video game edition!)
Super Robot Wars and Another Century's Episode. For the most part, the series consists of crossovers from an astoundingly large number of Humongous Mecha anime, though not all in the same game, or even timeline. Most games have also included original creations, both Real and Super, such as the Elemental Lord Cybuster. The original creations then got their own crossover with each other in the Original Generation subseries.
Size actually is a factor in combat calculations. When units with two different sizes are fighting, the bigger mech will gain defense and attack bonuses, while the smaller mech will gain evasion and accuracy bonuses. However, some attacks, like a Wave Motion Gun, can bypass these bonuses.
The Visual NovelDemonbane feature both mundane Destroyer Robot and Magitek-basedDeus Machina. While the eponymous Demonbane is 50 meters tall, the form it take in prequel novel, Gunshin Kyoshuu Demonbane (War God Demonbane◊) is the largest mecha in fiction, so big that actually destroys the universe it was in and collides with the neighboring ones. The final form, Elder God Demonbane, while not as large, has an ability known as Athleta Aeternum which allows it to summon itselves from all infinite universes, including those from realities that shouldn't exist. Nyarlathotep gets rid of the Gunshin Kyoshuu by altering the timeline of the multiverse, removing it from existence. She still keeps losing to Elder God form in their eternal fighting.
Metal Gear in all its stomping, nuke-launching incarnations. There's always a rationale (a missile platform which isn't limited to normal terrain) but the series makes light of the implausability anyway. Implicitly, as REX from MGS was designed by a brilliant but eccentric otaku, and the rest of the world has been caught in a REX-pirating arms race ever since. Explicitly in the prequel MGS3 when the idea of a walking tank is openly derided.
The fourth game even features a fight between Metal Gears, with Snake piloting REX from MGS1 against Liquid Ocelot in RAY from MGS2 This is the only time the Metal Gear series has actually allowed you to pilot a Metal Gear.
Peace Walker takes it further, with the usual Quirky Miniboss Squad being replaced by a collection of (mostly non-nuclear) mechas. The group includes: The Pupa, an all-terrain tank; The Chrysalis, a flying railgun mech; The Cocoon, a small base on wheels that requires climbing; and Peace Walker, a nuclear mech.
After beating the game, the player even gets their own Metal Gear mech (which also resembles REX), using parts gathered from all of the other AI weapons, though it's only for sending away on missions like soldiers. It later becomes the True Final Boss.
in Metal Gear Rising: Revengeance, a spin-off set after Guns Of The Patriots, Raiden fights a customized Metal Gear RAY as the game's first boss. Then all sense of scale is thrown out of the window at the end of the game when Senator Armstrong pilots the all-new Metal Gear EXCELSUS, which dwarfs both REX and RAY. Notably, it was intended to be Overkillingly huge in order to counter the growing use of cyborg soldiers.
Also, giant war machines usually in the style of AT-ATs are occasionally fielded as Mini-bosses/Elite Mooks, especially if the enemy commander is Chosokabe Motochika.
The Giant of Babil (spelled as Babel in Final Fantasy IV Advance) of Final Fantasy IV. The entire plot of the game, wherein the Big Bad's forces steal the elemental Crystals, was all performed so they could use the Crystals' power to send the Giant from the Moon, through the Tower of Babil, and to the surface of the Earth, whereupon it would raze the entire planet. Although scale is difficult to convey with super-deformed characters, it is implied that the Giant is several thousand feet tall.
Easier to determine in the 3D DS remake. One of the Dwarves' tanks barely reaches to what would be the Giant's toe.
The various incarnations of Alexander in the Final Fantasy series seem to be built out of enormous castles which were then modified into mobile robots. The first iteration, in Final Fantasy VI, even has towers and smaller castles built on top.
Final Fantasy VII had a mecha called 'Proud Clod' as a boss in the later part of the game.
Final Fantasy IX has the summon Ark. It's not just a summon; it's a Transformer!
Final Fantasy X has loads of these. At one point, it's a boss (as you attempt to leave the Calm Lands), but they live in the Zanarkand Ruins. Inexplicably.
Final Fantasy XI has one in the lore and one in assumption. While the version of Alexander that is fought as a final bossfight in the Aht Urghan expansion is only about 3 or 4 times the size of a player character, the fight itself takes place in a clockwork decorated undersea ruin that has been broken into five separate pieces but connected by teleport pads. Take a wild guess what Alexander's last incarnation was.
The second reference is made by one of the personality types for the player's NPC ally, who muses about how the legs, head and body of a secret weapon could be hidden under three of the larger features of three of the cities (A chapel, a giant tree and a tower).
Final Fantasy XIII, Eidolans are depicted as huge mechanical beasts that emerge to challenge whooever they're bonded with at their moments of Despair Event Horizon. Aside from helping you fight, they can transform into horses, cars, bikes, and gigantic fortresses during the "drive" mode.
Not to be outdone, Dark Cloud 2 (also known as Dark Chronicle) also has a gigantic flying fortress, Paznos. Although it was only supposed to be a mobile battle station, Max and Monica's tampering with the timestream further allowed its creators to transform it into a humanoid mecha strong enough to catch, stop, and toss an equally huge flying castle which was about to fall on top of a city.
Goemon Impact of Ganbare Goemon. People tend to remember him by his Image Song, which begins with a shout of "DA-DA-DASH!" (He's actually an alien that just happens to look like a robot. All righty, then...) Impact is also an international movie star that wears roller sandals and shoots bullets out his nose. No, really. And why, you ask?
The One Must Fall video game series was designed as a fighting game where hundred-meter tall robots remote-controlled by people smacked the [...] out of each other for profit.
StarCraft II features the Thor, a mecha so humongous that for a time it had the distinction of being the only Terran unit unable to be produced from a structure (and had to be built in the field). Its ridiculous size becomes the target of numerous in-game jokes. The Protoss, meanwhile, have access to the deadlyColossus, a ground unit so tall it can actually be fired upon by anti-air.
The campaign also features the Thor's Super Prototype, the Odin. While Thors take up a normal dropship's entire cargo capacity the Odin cannot be transported by any game unit, even the Hercules transports that can carry three Thors.
They are all trumped by the April Fools unit known as the Terra-tron, a unit that consists of a bunch of Terran buildings combined into a Super Robot sized killing machine that makes the Thor look tiny. Terra-tron, terrorize!
The Warcraft series gained Humongous Mecha with the third installment, which introduced large golems. The Frozen Throne, the expansion pack for Warcraft III, introduced very large golems.
The Burning Crusade expansion for World of Warcraft also introduced the Fel Reaver, which is essentially a giant steampunk robot powered by demonic energy. And they are terrifying.
The goblin-made shredders are giant robots primarily used for chopping down trees, but are also more than capable of chopping down people.
In Ulduar, one mech stands out... obviously I'm talking about XT-002 Deconstructor! This is an ENOURMOUS mecha, able to tear a warrior apart in a matter of seconds. It has the mentality and the voice of a little child and it considers you, the raiders, as his toys. When he kills someone, he says, "I guess it doesn't bend that way...". Funny, yet somewhat creepy at the same time. There are guilds raiding XT for the first time... seeing the towering mecha and preparing for an epic battle... and wiping because as soon as the boss was aggroed, everyone started rolling on the floor laughing over his voice. "New toys? For me? Oh, I promise I won't break them this time!"
Also, Mimiron's final form.
A recent patch added the Sky Golem engineer-made mount. It looks like a steampunk robot with a goblin's face for a chestpiece. It flies (even doing barrel rolls!) and lets you pick flowers without dismounting.
In the final battle of Fallout 3, has Liberty Prime stride purposefully towards the Jefferson Monument, crushing Enclave power armor troopers underfoot, vaporizing others with eye lasers, and tossing miniature nuclear bombs like footballs, all the while loudly proclaiming that death is better than communism.
The Mogenar of Bryyo from Metroid Prime 3: Corruption count as well. Yes, you even fight one.
The mechs in the Crusader series of video games aren't humongous, per se, but they can get bigger than any human and pack some serious firepower. Also, the end boss of No Regret wears a battle suit that appears to be about ten feet tall.
In Command & Conquer, GDI had plenty of mecha in Tiberian Sun, from the chaingun-toting Wolverine scout walkers, to the Titan walking tanks, to the Juggernaut walking artillery platforms, to the Mammoth Mk II, which sports railguns. C&C Tiberium Wars, on the other hand, was mostly a subversion: the Juggernaut was carried over, Nod got an Avatar walker, and the alien Scrin got a tripod straight out of The War of the Worlds, but in-game fluff material mentioned how the factions were discontinuing walker production, because commandos kept running up and disabling the things with a well-placed explosive on a leg joint. Indeed, the factions' commando units can do just that in-game, taking down an enemy walker instantly. Regardless, the Mammoth Mk II reappeared in Tiberian Twilight as the AW-12 Mastadon, now sporting sonic cannons. Meanwhile, Red Alert 3 introduces the "King Oni" mecha on the Japanese side and the official website data does some Lampshade Hanging on the concept, noting that it "flies in the face of decades of conventional mechanized warfare".
Shogun Executioner, which has three legs, three torsos, 6 arms, three heads, 3 lightning katanas, and heals itself when attacked with Tesla weaponry!
Slightly less awesome are smaller Mecha Tengu, which are in essence Valkyries designed to look as a 50s jet fighter, Striker VX, chicken walkers that transform into helicopters(Transformers, anyone?), and Steel Ronin, Wave Motion Glaive-armed Humongous Samurai Mecha. Which somewhat resemble those from Tengen Toppa Gurren Lagann. What, Gundams suddenly became less awesome, judging from the complete lack of Gundam ripoffs?
Or the Nod Redeemer, an Avatar on steroids with the added ability to cause a Hate Plague.
There's also CABAL's Core Defender that appears in Tiberian Sun: Firestorm. It makes Mammoths Mk. II look puny, its BFGs can kill anything in 2-3 hits, and they have rate of fire like machine guns. It takes an army (or destroying a bridge it's crossing) to beat it. The Kane's Wrath expansion to Command and Conquer III also has an upgraded version of the Scrin's tripod mech called the Reaper Tripod. The Scrin also have a giant 6-legged bug monster mech called the Eradicator Hexapod, though people tend to say it's the worst epic unit because its special ability is bad.
Metal Fatigue is an RTS built on this trope. There are non-mecha units, but even the one designed specifically against mecha is useless against decently armored models.
In Supreme Commander, three of the four factions get in on the act-the Aeon use the Galactic Colossus as the sci-fi equivalent of a battering ram and the Seraphim Ythotha is a relatively inexpensive multipurpose superheavy assault unit. The Cybran Monkeylord diverges from the standard Humongous Mecha type a bit, being a vaguely insectoid six-legged weapons platform, aptly nicknamed the spiderbot. They also have a crab-shaped amphibious mecha called the Megalith. And there are the ACU/SCU and Siege Assault Bots for each faction.
Most walkers in Supreme Commander are Humongous Mechas, with the exception of Light Assault Bots. The aforementioned Monkeylord dwarfs base structures.EVERY SINGLE ONE OF THEM◊. And it is the smallest of all experimentals! The Galactic Colossus is at least humanoid, but an ACU is about chest-height to it. Even the LIGHT 'mechs', such as the UEF Mech Marines, are the height of full grown spruce trees.
The community eventually worked out that 1 'unit' in the first game is about 19.5 meters. The aforemntioned Mech Marine, the smallest unit in the game, is 1 unit tall. The smallest thing in the game is bigger than your house.
Tech Romancer, a fighting game featuring humongous mecha inspired by super robot and real robot anime series.
Daggerfall also had Numidium, which was so massive that the God of Time threw the space-time-continuum off-balance by accident from the shock of it being turned on. According to Back Story, Tiber Septim could never have built an empire without it to fight. Morrowind followed this up with Akhulakhan, which Dagoth Ur was trying to construct using ancient Dwarven schematics and the severed heart of a dead god.
This comes to its conclusion in C 0 DA, where Numidium makes its big comeback as the primary obstacle, having successfully destroyed the world and unbound time.
Most of the Big Bads in the Ratchet & Clank series use mechs for their final showdown with Ratchet. (About the only one who doesn't is the Mutant Protopet in "Going Commando") Semi-lampshaded by Gleeman Vox in "Deadlocked"
Vox: And now, an audience favorite-the giant mech climactic battle!
Dr. Nefarious, in his appearance in "A Crack in Time", refrains from it.
And Giant Clank probably qualifies as one too.
The Xbox game Steel Battalion required a massive controller with tons of buttons costing $200 which was supposed to resemble the cockpit controls of the Humongous Mecha. One of the controls is a red ejector button that flashes when you take critical damage and is covered with a lift up cover. If you don't eject in time, your saved game is wiped and you have to start the game again.
Dr Eggman really loves these, and will usually be riding one during the non-Super final boss portion of each game.
And then there's the Gaia Colossus (do golems count?), which is made from temples! I couldn't [...] this one if I tried.
First there's Captain Blue's mecha, Six Majin. It's about as big as Voltron, and towers over city buildings.
At the end of the first game, Six Majin is seen again, but is now big enough to circle the earth in a few strides.
Things get truly ridiculous in the second game, where Six Majin and a new machine called Great Six Majin combine to form 6x6 Majin, who is bigger than the planets (its fist is only a few times smaller than the Earth). This is itself a counter to the final boss' Black Kaiser, which is bigger.
You never actually fight Dist himself in Tales of the Abyss, but you do fight a series of mechs he constructs using fontech.
Likewise in Tales of Innocence, where Mad Scientist Osbald is working on powering Humongous Mecha using People Jars filled with Reincarnated. First you free a party member being used as the fuel cell, then you find the mass-production model on a battlefield, and finally Osbald pilots one against you himself, using as the power source Ricardo's "brother", Gardle.
The recurring enemy Murder and his ilk range from dog-sized Spider Tanks to full-blown mecha that reach to the top of the screen.
A steam-powered mecha appears in the fourth chapter of Limbo of the Lost to save the day.
The first part of the final boss in Disaster: Day of Crisis turns out to be an experimental mechanised war machine, complete with arms and a missile launcher. It look like Evans had stolen a Metal Gear. Though, the designers were actually sensible enough to protect the cockpit... Doesn't stop Ray from taking it out, though.
Armored Core: High-speed (in the later games) combat using mecha that you build yourself from the ground up. The biggest appeal of the game is that whatever mech you use, you built it yourself. Which requires the mention of it's younger brother;
Chromehounds. Just as much, if not more customizable, with the major difference between it and the Armored Core series being about 300 MPH. Loved/hated because of it's speed, it places mecha combat in a more realistic (all things being relative) setting, keeping the focus on blowing stuff up while changing the game from "fly fast and Shoot Everything That Moves" to a more tactical game. Squads that fail to utilize the different role types and don't have an effective commander quickly find themselves scrap metal.
During the Neroimus War, each nation has its own "Unidentified Weapon" that acts as a superboss to help out a country on its last legs. The Sal Kari Unidentified Weapon, the Ghalib, is about 210 feet tall, but has a maximum height of around 330 feet when it opens up its heat-seeking missile silo. A large ACV squad accompanying you, seeing this silo, open fire. The Ghalib not only receives virtually no damage from their combined attacks, but then proceeds to wipe them all out with a single salvo.
City of Heroes has the Titans used by the Malta Group- the Kronos Class Titan is the size of a building. But, that's nothing compared to the giant robot at the end of the Ernesto Hess Task Force, though it's sadly inactive.
There are two equally-large giant robots in the third mission of the Imperious Task Force, although they are likewise there as window-dressing.
Also, in the Mender Silos Task Force (Strike Force for villains), the Jade Spider is a Humongous Mecha, powered by a strongly-psionic operator, sent by Lord Recluse into Siren's Call to destroy Paragon City. This one does fight, either against the heroes in the Task Force, or as an ally of the villains in the Strike Force.
Power Dolls, unusual in that authors both justified it (colonists weaponized a line of power loaders to defend themselves) and considered tactical problems: first, there is beyond-visual-range action, but stealth "shields" shorten the detection range, big target or not; second, PLD got lesser Endurance than a main battle tank (60 X3A/75 X3AC vs 70 M43T/90 M58T) and thus have to use good tactics relying on artillery support, stealth and slightly better sensors.
In Universe at War: Earth Assault, the Novus heroes Mirabel (a Human Alien with a tatoo on her head) and Victor (Her powered armor with an AI package) tower over the human sized Ohm Robots and Masari, and let her go toe-to-toe with Heirarchy hero Orlok and Grunt troopers.
There's the Hierarchy's The War of the Worlds-inspired walker units, which also serve as their production structures. They are heavily armed with guns that fire plasma projectiles the size of small cars for standard weapons, and be customized with more guns like those, anti-air guns, heavier, bigger guns, and the ability to bring in different units. They are the apex of the Mighty Glacier, they are so big that they can crush most anything, including structures, but they are the slowest units in the game. The Hierarchy's units as a whole as the slowest, but their walkers move at a snail's pace even compared to them.
In the Civilization IV mod Next War, you are able to build Juggernauts, the second most powerful unit (behind Dreadnoughts) in terms of raw Strength, which are walking tanks. The Civilopedia lampshades how impractical mechs are compared to regular tanks, but notes that the world's militaries poured tons of money into them because they're just too cool.
Civ V has Giant Death Robots if you reach the Future Era.
The Jak and Daxter games have several: one serves as the final boss in the first, and the third has two: one that wraps up the first act, and one that is as big as a freakin' city serves as the final boss.
Megaleg in Super Mario Galaxy is a giant three legged Snifit-shaped robot that fires Bullet Bills, and is bigger than the moon it's standing on. There's also Mecha Bowser in this game and Super Mario Sunshine.
Although not in terms of design, there was King Boo's Bowser mech in Luigi's Mansion, although very intricately designed and powered on magitech. Could be one of those fake Bowsers from the original Super Mario Bros.. for the NES though.
In the second game, there's a giant humanoid robot called Megahammer (according to Mario Wiki) with multiple Bullet Bill/rocket launchers fought as a boss, as well as a smaller version of Megaleg (Digga-Leg) to be defeated using the drill powerup.
In Mario & Luigi: Dream Team, there's the Robo Drilldigger and Earthwake bosses, both of which are fought as Giant Dreamy Luigi. The former is a huge robot thing with drills for hands that turns into a tank, the latter is a huge robot guardian made of buildings that can become things like a giant floating hammer.
In Mass Effect, among other bad boys, you fight a species called geth, who are robotic mobile platforms that house programs (concept revealed in Mass Effect 2) that range from small sentry turrets, to humongous spider like mechas that are almost impossible to kill without a tank.
Mass Effect 3 has Reaper Destroyers, small Reapers used for ground assault. Yep, "small". This is how big they are.◊ It also turns out the Reapers themselves qualify; they're capable of moving around on a planet's surface as squid-shaped mecha taller than skyscrapers.
In Mass Effect 3, Cerberus soldiers sometimes use large Atlas mechs, which are outfitted with rocket launchers, a scaled-up shotgun, and can one-hit-kill anyone in melee range. If your aim is sharp enough, you can kill the pilot without destroying the mech, then commandeer the mech for yourself.
Evil Twin Cypriens Chronicles has the Sea Sewers, robots so huge that they are able to cross the sea by walking over the sea bottom. They are tasked with decimating every last trace of the old world.
Towards the end of Enslaved: Odyssey to the West, you and your allies capture the Leviathan, a truly humongous mecha, which dwarfs all other humongous mechs in the game. You even have to fight a giant scorpion mech on top of the Leviathan!
Kingdom of Loathings MagiMechTech MechaMech: "It fires a torpedo at you. A pink torpedo. KAWAIII!! I mean, OW!". It's more of a Mini-Mecha, but even more Fun Size versions are the MagiMechTech MicroMechaMech (say that three times fast) and MagiMechTech NanoMechaMech.
Ōkami's final boss, Yami, the lord of darkness, is a small fish-shaped thing. He pilots a spherical mech, capable of numerous different forms and attacks, including one that extinguishes all light in the area.
Sanae and Cirno's respective story lines in Unthinkable Natural Law (12.3) involve them chasing after a huge human-shaped shadow, which Sanae believes to be a giant robot. Subverted at the end of Sanae's story though, when you find out that it is actually the Hisoutensoku, which is a large steam-powered mannequin that lacks the ability to move freely.
Raidou Kuzunoha vs. The Soulless Army has the Soulless Gods Oumagatsu and Yasoumagatsu, Taisho-era dreadnoughts retrofitted into towering, bipedal monstrosities which still happen to be very heavily armored and loaded with enough cannons to level cities and thermic rays. The main flaw of the model? It requires absurd amounts of spiritual energy to work, and once cut off them, the organic parts just melt.
Champions Online has several. The final boss of the Destroids Rise Again! open mission is the Mega-Destroid, a cosmic-level enemy (there are, broadly speaking, six levels of enemy in the game: Henchman, Villain, Master Villain, Super Villain, Legendary, and Cosmic). In the Resistance mission, the Big Bad of the alternate world of Multifaria uses lesser Mega-Destroids that have a slightly different, more inhuman appearance; they're at legendary level. Just before the final battle, you get to pilot one, making them true mecha, not just giant robots; you also use them to fight giant magical golems, which kind of count. There is also the Black Talon at the end of the tutorial missions; created by Doctor Destroyer himself, the Black Talon is probably the first size up from the line between Powered Armor and full scale Humongous Mecha.
Disgaea 4: A Promise Unforgotten gives us Super Alloy Great Flonnzor X, the 'secret weapon' brought to us by our favorite otaku-angel Flonne. Ships purchased through DLC also include the Laharl Kaiser V and the Getter Mao.
Kirby introduced one in Kirby's Dream Course as the final boss: a giant robot Dedede. Later, in Kirby 64: The Crystal Shards, another one, the HR-E/H, appears as the fifth boss. Dedede, who was helping Kirby in the latter game, decided to redesign his robot with attacks that the HR-E had, creating HR-D3. He used it against Kirby in the Kirby Mass Attack sub-game Kirby Quest, but it was defeated. By Kirby's Return to Dreamland, it somehow drifted to Halcandra and was found by the Mini Mecha Metal General, who takes it over and redesigned it in his image. In Extra Mode, after the Metal General EX's health is depleted, he summons HR-D3 and fights Kirby, Meta Knight, Bandana Dee, and Dedede himself with it, after which the two robots are destroyed.
In Intrusion 2 The final boss MACE is a giant robot, complete with Eye Beams, giant missiles, and huge electrified fists that also shoot lasers.
The 5th Bloons Tower Defense game brings us the Technological Terror, which is somewhat bigger then most towers & its also very effective against M.O.A.B.-class bloons because it fires its own special green plasma which is equivalent to 2 streams of the normal purple plasma. What makes it destructive, though, is the fact that it fires 2 streams of it.
To say is short & sweet, against M.O.A.B.s, even Sun Gods & Rays of Doom are outclassed by it. Against swarms of regular bloons, though, the Sun God & Ray of Doom are far superior.
In Sunrider, called Ryders. They make up most of your team during battle.
Copy Kitty has the Virs golems. While they're made of stone, they are animated by magic. They're small enough to be considered Mini-Mecha, but the giant-sized version, the Fortress Virs, definitely hits the "Humongous" part of the trope, and is said to be capable of fighting an entire army on its own. The Dengrahx and its giant version, the Giga Dengrahx, are similar (the Giga version is the size of a small mountain), but with one big difference: they're not humanoid, they're fire-breathing Spider Tanks!
In MegaTokyo, the police cataclysm division (which facilitates cataclysms like 'zilla, zombie, and alien attacks, as long as they are done in an orderly fashion) employs mecha. They turn out to be less effective than robot-girl Ping.
Titanzer, the main character's robot and title of the webcomic.
Stubble Trouble once showed a giant robot tearing up the city while fighting several superheroes. Guests from another webcomic (in a crossover appearance) wondered why nothing this cool ever happened in their town.
Ilivais X is a mecha anime in Web Serial Novel format, using both Real Robot and Super Robot influences. The eponymous mech (and the others like it) are more streamlined and shiny and just futuristic in general than other examples present.
Transformers and the various series showcase a Western version of the archetypical transforming mecha. It's especially notable because unlike the usual mecha show, there are no pilots or crew to be the stars - the mecha themselves are the stars, being sentient robots.
It has been speculated that the on-and-off popularity of Transformers in Japan is because it lacks pilots or other very important human characters... usually. When annoying kids are put in, the American fanbase, which is much larger and more consistent, shudders.
The Japanese versions of Transformers appear to support the theory that giant transforming robots without pilots are alien concepts in Japan. While the Western series give reasons for their alternate modes (disguise, protection from radiation, etc.), the Japanese series, such as Transformers Armada, generally disregard them-although, as the series exist to advertise toys, they transform anyway. This reached ridiculous heights in Transformers Energon, where the Transformers, capable of flying around in space in robot mode, transform and drive in space. The Japan-only G1 sequels were better about it.
Speaking of those, it's an interesting inversion: Headmasters, Targetmasters, and Powermasters are, in America, humans or humanoid aliens in Powered Armor that transform into the heads, weapons, or engines (respectively) of larger Transformers, coming as close to making the T Fs piloted mecha as possible (do we have to tell you how that went over? Of course, now, those eras are sacred for being part of G1 instead of those sacrilegious later series.) In Japan, though, the armored forms of Headmasters were now small robots and the larger partners were unliving "Transtectors," built by the small robots to combine with for greater power. Not a squishy "organic" in sight.
Even in a show of humongous mechas, some of them were EXTREMELY humongous. There was Sky Lynx and Omega Supreme, who were overshadowed by the fortress-bots Metroplex and Trypticon, who were in turn dinky compared to the city-bots Fortress Maximus and Scorponok. To say nothing of the Chaos Bringer, Unicron, or the Transformers' creator god, Primus, who are freaking planet-sized Transformers.
Voltron was, for a time, the best-known example in America. It was an amalgamation of two fairly obscure and almost completely unrelated shows, Go Lion (Lion Voltron) and Dairugger XV (Vehicle Voltron), along with some Lion Voltron episodes produced by Toei especially for the American market.
Cartoon Network's Megas XLR is possibly the best Western parody, with an alien robot from the future crash-landing in a New Jersey junkyard, where the main character, Coop, buys it for two bucks... which he never actually pays.
Parodied in Total Drama Island, where Duncan, while trying to catch a raccoon, faces a horde of raccoons forming a huge machine-like army by standing on top of one another. Duncan comments that it's "more than meets the eye!"
Parodied again during Action. Harold and Beth have to fight in ones during the Kung Fu challenge, but they turn out to be very simple, giant versions of Rock 'em Sock 'em Robots with Duncan and Courtney controlling them.
Chef's giant plasma TV transforms into a humongous mecha at the end and goes on the rampage.
Barbra Streisand transforms into a humongous mecha and goes on the rampage. However, it's not a not humanoid but a godzilla-like machine. The word 'mecha' is used in the episode to describe Ike, who's merely giant and not mechanical in any way.
Brian Boitano traveled through time to the year 3010, fought the evil robot king and saved the human race again
Parodied in Pinky and the Brain: Brain and his archnemesis Snowball the hamster are battling in their robotic human disguises when suddenly Snowball's suit transforms into a Humongous Mecha, complete with rockets blasting out of its shoulders...
Parodied in The Venture Bros.. Season 1's "The Trial of the Monarch" features Hank & Dean's fanciful retelling of a battle with the Monarch in which they become "Mecha-Shiva". Season 3's "The Lepidopterists", Jonas Jr.'s team form a Voltron like mecha to take on the Monarch.
Just as in the Comicbook entry above, the eponymous Big Guy from Big Guy and Rusty the Boy Robot is one of these, though the public are under the impression that it's fully automated.
The mecha tanks in The Legend of Korra were created by Hiroshi Sato for the Equalists. Team Avatar and even Tenzin have to try and fight them throughout the latter half of Book 1. And in the end, Asami Sato gets into a final showdown with her father with this machine, which she said works like a "Future Industries forklift".
Code Guardian, set during WW2, has a giant German mecha duke it out with a giant American mecha as the former tries to destroy a naval ship yard only to have a giant Japanese samurai mecha show up at the end.
Destroy The Godmodder 2 uses these as the basis for the godmodder's armies fairly often, usually in the shape of Minecraft mobs.
There are lots of others, Optimus Prime and Redeemer Hitler being two examples.
Some kind of weaponized excavator would come pretty close to a more feasible version of the same concept, as demonstrated on one double-length Scrapheap Challenge special (albeit with smaller excavators then you'd need to really be this trope).
A company called Boston Dynamics developed a four-leggedMini-Mecha capable of carrying 88 pounds and withstanding significant force without falling over.  It's a bit... unsettling.
Though not a military vehicle, the civilian-made, six-legged Timberjack Walking Machine probably deserves a mention. 
Carlos Owens, a former army mechanic, spent four years and $25,000 to build an 18-foot tall steel mecha. No, really.
Japanese artist Kogoro Kurata has made one called the Kuratas. This has a diesel-powered wheeled spider-tank lower body instead of legs, travels up to 6mph, can be piloted or controlled with a smartphone, and has water-bottle-firing gatling guns activated by the pilot smiling! You can build your own for $1.5 million. Photo gallery here