Most tanks have tracks, some tanks have legs, while others have many, many legs. These tanks on the other hand, have chicken legs, or as they're officially known as "reverse-joint"note or digitigrade legs.
Most of the time a Chicken Walker is a Humongous Mecha or Mini-Mecha but occasionally backwards bending legs can be found on other objects, like buildings. While there may be some benefits to a leg shaped like this,note this design is usually chosen simply it because it looks less anthropomorphic than regular legs. This deliberate violation of one of the main tenets of character design — the one that states that machines must be humanlike to be relatable and aesthetically pleasing — is a quick way to signal to the audience that the robot in question is sits firmly on the Form Follows Function end of The Aesthetics of Technology. This is a particularly common design choice in military-themed Real Robot series.
Note, however, that chickens don't actually have "backwards knees", because the apparent "knee" is actually their ankle and heel joint (and their "ankle" a knuckle), while their actual knee is much closer to the body (and practically invisible under their coat of feathers). Same goes for horses, and most quadrupeds' hind legs.
That said, there is some credit for choosing this leg design for large walking machines. As stated in the Real Life examples section, the digitigrade leg structure has millions of years of theropod evolution to back its claim of being a highly effective bipedal leg design. And that's not even mentioning that human legs, which don't follow the digitigrade pattern, are riddled with problems
.
Subtrope of Walking Tank; see also Spider Tank.
Compare Bell-Bottom-Limbed Bots for another popular form of robotic legs.
For other awesome tanks check out Hover Tank, Drill Tank, and the Military Mashup Machine.
Examples:
- The Virtual Boy is depicted this way in this
commercial.
- In Super Dimension Fortress Macross, Super Dimension Century Orguss and Super Dimension Cavalry Southern Cross, the mech knees bend forward in full-humanoid battroid mode but backward in jet-with-legs GERWALK mode.
- Macross's Zentradi combat pods like Regult and Glaug also fit this trope.
- Earth mechs with Armo-Diver mode and the non-humanoid Invid mecha from Genesis Climber MOSPEADA.
- Most of the above also appear in Robotech, of course.
- Gundam: Although rare, a few MS have reverse-joint legs when transformed, notably the Gaza-C, its successors and Destroy Gundam.
- 20th Century Boys: the robot designed by the engineer whose daughter the Friend cult kidnapped ended up this way, instead of the blatant Tetsujin 28 ripoff they originally wanted.
- Aura Battler Dunbine has Botune.
It seem that the purpose of using this trope is merely to give audiences an impression that it's Fragile Speedster, since most of mech combat is aerial battle.
- The Storrian Military from Ark use tanks on two legs as default vehicles. They turned out to be Awesome, but Impractical as demonstrated in a chase scene - one Storrian tank ends up tripping sideways and hitting its partner, destroying both at the same time.
- 9 has the self-piloted Steel Behemoths — the Fabrication Machine's primary foot soldiers, who wiped out humanity with their chemical weapons in the film's backstory. None of them are active during the actual events of the movie, though, perhaps due to lack of maintenance — they're only seen sitting dormant in hangars.
- Star Wars has the AT-STs (the two-legged walking vehicles in Return of the Jedi) and their various derivatives/precursors (such as the AT-RTs in the prequels). In fact, they are often called "Chicken Walkers" by fans, and this is often referenced by game developers or showrunners. For example, in the original Rogue Squadron, the code "CHICKEN" even unlocks a mission where you play as an AT-ST. It's interesting to note that AT-ST legs actually behave more like a real chicken's legs, with the proper, forward-bending knee joint up high near the hip and the backward-bending "knee" down lower.
- RoboCop (1987) has ED-209. Heavily armed, extremely intimidating, but can't even walk down a flight of stairs or down a street. In the second film one gets stuck in a manhole.
- Chappie has the Moose, an homage to ED-209.
- Frankenstein's Army: There's a Chicken Walker standing in a corner of Frankenstein's main lab, although it doesn't move and may have still been under construction.
- The Themis Files: The aliens have digitigrade legs, and correspondingly, the controls used to operate their mechs require digitigrade legs. Vincent Couture, would-be pilot for the legs bit, undergoes some... intense surgery in order to match the alien anatomy.
- In Leviathan, Deryn notes that the Stormwalker moves like "a great iron rooster".
- From Kamen Rider 555, the Side Basher in Battle Mode.
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- The Blue Midget from Red Dwarf was retconned into "upgraded" version of Red Dwarf so they could do a dance number, originally being a tank-like vehicle.
- Falling Skies: The "meks" of the aliens walk this way, but are weirdly designed. Several characters discuss the possibility that the meks were specifically designed to intimidate humans, as the aliens themselves are six-legged. On the other hand, it could be a purely technical decision. It's not practical to build a large robot with more than 2 legs (4 max).
- Tweedledee and Tweedledum, from Andromeda.
- In Russian mythology, Baba Yaga's house moves around on actual giant chicken legs. This depiction originates from an ancient Slavic custom to put coffins (which is what Baba Yaga's house is supposed to be or at least symbolize) on four tree stumps, which do look a bit like chicken legs, due to the sprawling roots.
- Warhammer 40,000 has a number of mecha that follow this design:
- For the Imperium, it's the Sentinels of the Astra Militarum , the Warhound Titans of the Adeptus Mechanicus' Titan Legions, the Ironstrider Ballistarius and the Sydonian Dragoon of the AdMech's Skitarii Legions. Other walkers like the Imperial Knights (and their various patterns) and the larger Titans (Warhounds are scouts) are more humanoid, if hunched over depending on specific pattern or variant. More recently added, the Armiger pattern Knights (the smallest and their pilots are squires to pilots of larger patterns of Knight) also have the chicken design.
- For the Eldar, it's the Warwalker. Almost all of their other mechs are fully humanoid in design, basically ghost robots.
- The Tau's battlesuits are closer in appearance to actual chicken legs than most examples of this trope, with forward bending knees, high ankles, and several widely spaced, broad toes, mimicing the Tau's actual hooved feet.
- BattleTech: Roughly half the bipedal BattleMechs are like this, including fan favorites like the Timber Wolf (the signature 'Mech of the franchise and the image used on its Tropes page), Mad Dog, Bushwhacker, and Marauder, the rest using standard humanoid leg structure. Acknowledged by supplemental material by noting that chicken-walkers may traverse rougher terrain but are typically less speedy than man-walkers. However, despite being a game system known for having optional rules for practically everything, there are no rules for having chicken legs instead of humanoid legs.
- The second stage of the Spanish, Cabal-like, arcade game Alligator Hunt has your character fighting
◊ giant, chicken-legged, alien mechs attacking a city. Their bodies are spherical, though, and you'll need to aim for their heads and blow them up to make them collapse.
- Apocalypse: The war factory stage is staffed entirely by two-legged robots resembling the ED-209, serving as the sole Mecha-Mook variety in the game.
- Atomic Robo-Kid have huge, bulky, two-legged robotic enemies modeled after the typical chicken walker design (called "R6" in the credits) as occasional Giant Mook enemies.
- One of the bosses in Earthworm Jim is this, complete with a chicken head.
- WarGames Defcon 1 have walkers being the default attack units for W.O.P.R, armed with dual turrets for causing heavy damages. The game starts with the smaller MK-II Walkers, and later on introduces a far deadlier MK-IV Walker unit who can spam tons of missiles on targets.
- World of Warcraft: The gnomes have as their racial ground mount the Mechanostrider, a chicken-legged mecha resembling an ostrich or emu.
- Brigador's mechs trend toward this, but taking the cake are the Spacer factions' mechs, who love placing as much hi-tech heavy weaponry as they can on their mechs, and using even higher-tech alloys, servos, and engineering to make the skinny legs that carry them work.
- Command & Conquer:
- In Command & Conquer: Tiberian Sun, the GDI trades its tanks for the Titan, a chicken walker with 120mm cannon. The Firestorm expansion adds the Juggernaut, an artillery variant with triple the firepowernote that needs to be deployed to fire.
- They return to the use of tanks in Command & Conquer: Tiberium Wars but they do keep the Juggernauts as mobile artillery. In the Kane's Wrath expansion, the Steel Talons are a GDI subfaction, that brings back the Titans and even introduces a variant of the Juggernaut. To drive the point home even more, Juggernauts in CNC 3 occasionally comically peck just like chickens!
- Command & Conquer: Red Alert 3 generously donates the Empire of the Rising Sun's Striker-VX, an anti-air missile platform that can transform into an anti-ground missile helicopter.
- Metal Gear: All of the bipedal Walking Tank-type Metal Gear models (Metal Gears from non-canon spin-offs notwithstanding) follow this design, as does the bipedal mode of the Peace Walker AI Weapon, though the TX-55 Metal Gear and its two derivatives, Metal Gear D and the undeveloped Metal Gear Gustav, do away with the forward-facing knees in favor of backwards-facing ones. The birdlike look is actually lampshaded in the manual, which claims that the small, unmanned Metal Gear Gustavs are nicknamed "Ostriches" by troops because of the way they walk.
- In the 2023 April Fools event called "Titans Rise"
for Enlisted, they introduced the walking tanks which are WWII-style walkers. The USSR get Sh T-34V "Victor", the Germany has the Pz.Tr. X, and lastly the USA gets the WT-25 “Predator”.
- StarCraft: The Goliath unit, as well as its replacement, the Viking (walker mode), in StarCraft II.
- Basically the whole idea of Future Cop: L.A.P.D.. Well, that and Flying Cars.
- Genetic Species has the Wolfhead, gigantic bipedal robots on two legs as the largest and strongest mechanical enemy in the game.
- The Raptor from the second G-Police game. It had the ability to jump and glide (compared to most of the vehicles being planes, with one example of an armoured car).
- You can find many of this in Armored Core series. Befitting of a bird-inspired design, they're better in the air.
- The first boss from Super Meat Boy called Lil' Slugger is one armed with saws and a chainsaw.
- Biomechanoids from Serious Sam series are like that. Coincidentially, the biological parts of these walkers are bird tissues. There is a Chicken Walker enemy in Serious Sam II, too which is called Torso Mech - The Nervous Chicken.
- Top Hunter: Roddy & Cathy allows you to hijack bipedal, two-legged tanks from enemies and use them to kick ass. Enemies getting trampled by your mech gets Squashed Flat and floats away comically.
- You pilot one of these in Battle Corps, called a B.A.M or "Bipedal Attack Machine".
- MechWarrior, being based off BattleTech, gets in on this as well with quite a few reverse-joint 'Mechs. The games give some of them a marked hopping-bobbing gait, which can be a bit tough on targeting at times. Chicken walkers in the games typically move faster, but aren't as good at scaling hills or mountains as man-walkers - Mechwarrior Living Legends features the Thanatos, a mech with anatomically-correct chicken-legs
◊, which is very fast for its weight, but has trouble scaling >30% grade hills.
- The Spin-Off series MechAssault contains these mechs as a majority of their roster, such as the Cougar (Jack of All Stats with a Jump Jet, two Pulse Lasers, one Auto Cannon, and two Javelin Missiles), the Catapult (support-oriented Mighty Glacier with four Pulse Lasers, four Javelin Missiles, and the longest lasting Jump Jets in both games), the iconic Madcat (offensive-oriented Mighty Glacier with two PPC's, four Javelin Missiles, and two Machine Guns), and much more.
- In one level of Futurama: The Game, you get to ride in a literal Chicken Rider.
- You spend the entirety of The Divide: Enemies Within piloting a two-legged chicken-walker-esque mech exploring an alien planet infested with hostile creatures.
- A literal one in Donkey Kong Country Returns, which serves as the boss of World 7. And yes, it's piloted by a chicken.
- In Chrome Hounds, you can build your very own, officially known as reverse-joint chassis. The leg form gives enhanced recoil consumption, making them good for light artillery and sniper mechs.
- The Flapper species in M.U.L.E.. No surprise, since they are human-sized birds.
- The Star, Panzerstar and Sturmvogel enemies/boss from Einhänder. Interestingly enough, their names mean "Starling", "Armored Starling" and "Thunderbird" in German, quite meaningful when compared to their bird-like legs.
- The bipedal geth units from Mass Effect have digitigrade legs, based on the physiology of the quarians that created them.
- All of the "light" mechs of Hawken use this configuration.
- Walker: The AG-9 Walker has very bird-like "feet" and its head resembles a bird skull.
- Rendering Ranger: R2 have an alien walker machine as one of the bosses, where the only way to damage it is by shooting upwards at it's head. Oddly enough, unlike other examples this particular walker won't try stomping you under it's feet, allowing you to walk directly beneath it.
- Light AFW's from Ring of Red. One model even looks like a mechanical chicken, with a machine gun for a face.
- The Data East arcade game, RoboCop, brings back the ED-209 units from the film, as recurring Giant Mook enemies larger than the titular hero.
- Eggy,
an old Japanese computer game, stars a mecha named Ena that walks like this, though it can hover too.
- Sonic the Hedgehog Chaos: The final boss, the Laser Walker, is such a device during it’s first phase. In the Japanese release, it’s even called the “Killer Turkey”.
- Sonic the Hedgehog CD: The first boss from Palmtree Panic is this, with spiked feet.
- Sonic Adventure 2 has both of the Mini-Mecha piloted by Tails and Eggman.
- Halo:
- The Mantis is a bipedal mech used by the UNSC, first appearing in Halo 4. Its much larger cousin, the Colossus from Halo Wars 2, also has digitigrade legs, though this may be not particularly noticable at first glance due to how straight it stands.
- The Reaver from Halo Wars 2 is a bipedal anti-aircraft walker used by the Banished. It even has an appearance reminiscent of a theropod dinosaur.
- In both Battle Zone 1998 and its sequel, all combat Humongous Mecha utilize chicken walker designs. The NSDF "Sasquatch" of 1998 uses a "man-walker" design with a torso and arms with chicken legs, while the CCA "Golem" has chicken legs bolted directly to the sides of the body with no arms. In Battlezone II, the ISDF "Attila" uses a bizarre layout where the chicken legs are connected to a pelvis which supports the torso under it, riding between the legs, while the Scion "Mauler" has a pair of chicken claws that pull the rest of its stabilizing legs along the ground.
- In Star Fox Zero the Arwing Space Fighter can transform into a chicken walker known as the "walker". It's used to get into tight spaces and narrow corridors you normally couldn't fly through. Fittingly it even resembles a chicken
with short wings on the side, a tail like fuselage, and bird feet.
- Rogue Squadron: The original has a secret bonus level where you control an AT-ST, one of the gangly-legged walkers from Return of the Jedi. The only way to access this level was to input "CHICKEN" in the cheat menu.
- It's subtle since they lack digits, but the legs of both MEC Troopers in XCOM: Enemy Within and SPARKs in XCOM 2: Shen's Last Gift have this anatomy.
- Empire Earth: a few of the cybers available from the Digital Age onwards have this type of design, namely the Minotaur and Zeus units, but the designs are generally broad. The pattern is repeated in the sequel.
- The Corpus from Warframe produces and uses numerous forms of MOAs, turret robots walking on a pair of digitigrade legs.
- Shadow Complex has the WSA1 Walker, a towering bipedal mech with reverse-jointed legs.
- Crusader: Other than the Cametron, all the anti-personnel mechs have reverse-jointed legs
- One type of enemy variant in Ghostrunner is a stationary turret with largely decorative chicken-legs. They can launch massive horizontal blasts at the Ghostrunner with unparalleled accuracy.
- A common Clank design in Girl Genius. For example, Gil's Fencing Clank.
- Problem Sleuth's candy mecha is a sentient example. In fact, even after the head is detached so that it can fly off to fight the villain, the legs still are used for various purposes.
- Kim Possible had giant robotic flamingos.
- Invader Zim: Thanks to a Defiant Captive shipping, Zim receives a MegaDoomer stealth mech from his superiors. Gir provides the page quote upon first seeing the mech, to Zim's irritation.
Zim: (Growling) Yes. Chicken legs.
- On Jimmy Two-Shoes, this is one of Heloise's many machines.
- Large Theropods
could be considered biological versions of this. So can small bipedal rodents such as jerboas, although they hop more often than they walk.
- Boston Dynamics's Big Dog robot is structured like this, with digitigrade design.