Spider Tank



"Artemis Gordon: Ok, What does Loveless have? (notices factory complex) Oh... he has his own city. [out of nowhere a giant mechanical spider shows up] Jim West: He's got an 80-Foot Tarantula.

Artemis Gordon: Yes... I was getting to that."

- Wild Wild West

A subset of the Real Robot Genre, with a decidedly non-humanoid appearance. These are often used by sci-fi series that want to use giant robots, but feel that humanoid shapes won't fit the setting. Even if the setting doesn't use giant robots, and sometimes even if it does, smaller Spider Tanks may be found as robotic drones. In series that use giant humanoid robots as well as spider tanks, you can bet that the humanoid robots will often be more agile than their multi-legged counterparts, despite the fact that the opposite logically would be true.

The form has a number of advantages over the human shape: lower to the ground (thus less of a target). Your classic Spider Tank spreads its legs out more, making the vehicle more stable overall and allows it to traverse terrain that would give wheeled vehicles considerable trouble. All of which helps it cheat that pesky Square-Cube Law that gives giant humanoids considerable engineering problems. (Of course many settings then turn around and give it pointy ballerina feet, ruining any overall improvement in the ground-pressure department, but hey.)

While wheels are faster and more efficient and tracks are best on a soft ground (it's hard to beat one big support area), spider legs can navigate extremely rough terrains and are more reliable because the vehicle can stand or even walk after losing a leg or two. Since "extremely rough terrains" include rubble blasted all over streets or hedgehogs made of rails and "losing a leg" includes little gifts from artillery, you see why an excavator isn't the only potential application. In fiction this means the spider design is most attractive for settings supposed to be gritty and realistic - exactly because it can believably retain some functionality despite a lot of visible damage.

Depending on the size of the Spider Tank, it may or may not have wheels on its feet. Caterpillar tracks are also common. If the Spider Tank is under 4 meters (roughly 12.5 feet) tall you can expect it to have wheels or tracks on its feet; if larger, you can expect it won't. It will probably have pointy feet instead. Despite the name, Spider Tanks rarely have eight legs. Four is the most common, and some have six. It's usually guaranteed that they'll have an even number of legs, though.

Please note, Spider Tanks are not tanks designed to look like spiders; they are simply tanks that walk like spiders (or scorpions). If you encounter a giant robot shaped like an insect or arachnoid it's more likely that they are a Mechanical Horse and not a true Spider Tank. In video games some Real Robot humanoid mechas occasionally have four or more legs, but still have an upper body and arms. They are also not spider tanks, as they do not fulfil the tank requirement. It's also not an arachnid version of the Snake Pit or Shark Pool.

A similar (and broader) concept is Tripods. See also Giant Spider and Giant Enemy Crab for their autonomous organic counterparts. Sub-Trope of Walking Tank and, depending on the type of Spider Tank, Starfish Robots.

Anime and Manga
"Tachiko-Man, Tachiko-Man, doin' the things a Tachikoma can...."
 * The Provisional Type Evangelion Unit-05 from Evangelion: 2.0 You Can (Not) Advance.
 * In the second to last episode of Genesis of Aquarion we find out that
 * Fuchikomas, Tachikomas, and just about half the tanks in Ghost in the Shell. They all have wheels or treads on their legs, save for one example from the first movie. Makes sense, since their walking speed isn't that fast, especially for car chases. Looks like someone did his homework on military doctrine this time.
 * Fuchikomas and Tachikomas also have the ability to cling to walls and deploy wires that let them swing around or descend vertical heights, meaning that unlike most other Spider Tanks, these ones actually are basically spiders, or rather, they're Spider-Man, in Tank form. The Tachikomatic Days omake lampshade and parody this.

"Tachikoma 1: [Worried about an impending confrontation with several Jigabachi] So, wouldn't anti-tank helicopters be like... our natural predator?
 * Ghost in the Shell also features the Jigibachi attack helicopters which resemble wasps, named for a type of wasp that hunts spiders. This is also Lampshaded:

Tachikoma 2: Hmmm... Mister Batou, can we go home? We have upset stomachs.

Batou: Stomachs? What stomachs?"


 * Staying with the Masamune Shirow theme: Spider Gun Platforms in Appleseed. The fourth volume of the manga also features smaller Attack Drone robots with actual abdomens that are almost entirely made up of a Minigun and its absurdly large ammo drum.
 * The GD-42 Battlemover in Bubblegum Crisis, the "crab mech" piloted by Vision.
 * A number of these show up among the Martian Robot Army in Mahou Sensei Negima. One in particular, is actually marked U.N. Mars Force.
 * A couple of spider mechs appear in Patlabor, including one for traffic police, one that's supposed to be a luxury civilian vehicle and a third one being a mobile command post used by United Nations forces. All three of them had wheels on the ends of their "legs".
 * The Type IV Gadget Drones in Magical Girl Lyrical Nanoha. Fast, deadly, four-legged Mecha-Mooks with two sickles that slice through Barrier Jackets like butter. The manga also showed experimental versions of Type III Gadget Drones (those big ball things) that were six-legged walking tanks.
 * In Fang of the Sun Dougram, the spider tanks are improved model of Walking Tank Crab Gunner and Tequila Gunner. They have lower profile and more mobile than their predecessor and come in two form. A six legs Desert Gunner and smaller four legs Blizzard Gunner.
 * Howls Moving Castle is a castle on legs.
 * A number of Scorpion-, Crab- and Insect-based Zoids, notably the Death Stinger.
 * A walking steam tank is shown for only one scene in Steamboy, being used by the O'Hara foundation when fighting the British military's treaded tanks.
 * All the mecha in Time Bokan are animal-shaped, from the insect-shaped robots used by the heroes to the assorted robots used by the Skull Trio.
 * The Takemicaduchi, A.K.A. Tank-kun, in Sora no Woto.
 * All the tanks seen in action are spider-tanks, but the Takemicaduchi is the most advanced tank ever built, a piece of Lost Technology.
 * In the Soul Eater Anime, this is what Baba Yaga's castle can become. A giant spider castle tank.
 * Even Gundam gets into the act. Although the Adzam Mobile Armor in Mobile Suit Gundam is more like a hovering gun platform with four landing gear, the Zamza-Zah actually has fully-jointed legs (with retractable crab claws and BFGs in the feet), though it also spends most of it's appearances flying. Destiny also has the Ghells-Ghe, which is an insect-like armor with the upper body of a mobile suit mounted centaur-like on the front.
 * Cyborg 009 had Monster of the Week Cyborg 0011, who's body was basically one such tank, with lasers, a cannon that shot a sticky substance.
 * Small, four-legged spider tanks appear in the Akira manga to enforce martial law after Tetsuo releases Akira.

Fanfiction

 * Anansi from Exoria. Twenty-five meters tall. Carries ten chain guns and dozens of anti-tank top-attack missiles. Runs at three hundred kilometers per hour. Impervious to most conventional weapons. Can jump.
 * The Nephilim Tsuchigumos of Aeon Entelechy Evangelion replace the useless canon Cthulhu Tech Nephilim. And yes, they are a Shout-Out to Tachikomas.
 * Go-Kun, of course, from Nobody Dies, but more classically the Reego (or some of their bodies, at least). Tres even has most of the semisentient giant spiders in Australia worshiping her. (Long story.)

Film
"Skinner: Tanks?! Oh, this is just too inaccurate. [Professor Frink appears behind him in a giant robot spider.]
 * Syndrome's Omnidroid in The Incredibles. Early versions had two wheels and two arms, but at some point they were mixed together and just kept increasing from there until you got the five- and six- legged, building-sized monstrosities that were actually fought.
 * Star Wars:
 * The original trilogy's AT-AT ("All Terrain Armored Transport") - heavy tank/APC - sort of qualify based on leg count, but ultimately they're less Spider Tanks and more Elephant tanks, as the AT-AT leg design and movements were based on elephants walking.
 * AT-TE ("All Terrain Tactical Enforcer"), more of APC/UCV than a tank, which is EMP-hardened and can be  deployed or evacuated via air by a special dropship/gunship (LAAT/c).
 * UT-AT ("Unstable Terrain Artillery Transport") - self-propelled artillery/APC - is a spider hovertank: it got 16 repulsorlift skis, armored and structurally separate like a caterpillar's legs, so presumably even complete destruction of a few would not cripple the vehicle.
 * On Attack Drone side of the spectrum, Spider Droids (large and small) from the prequel trilogy.
 * Wild Wild West: The giant Steampunk robot spider.
 * Producer Jon Peters repeatedly insisted a similar spider tank show up in early drafts of what later became Superman Returns, as wittily recounted here by scriptwriter Kevin Smith. It also shows up in Superman: Doomsday (though admittedly, it kind of looks more like an ant with one pair of legs too many.)
 * South Park sent the Wild Wild West Spider Tank, where Cartman pretends he's a rapping cowboy who has to save Selma Hayek from a big metal spider.
 * The Simpsons: parodies the Wild Wild West spider tank more affectionately in where Skinner tries to maintain realism in a Civil War re-enactment, despite the interruption from some nearby World War Two veterans...

Professor Frink: Well then, you're definitely not going to like my steam-powered super-spider. With the stepping and the squishing and the web made of NYLON"


 * Jon Peters' obsession with the vehicle goes beyond just those two movies. The most egregious example might be his attempt to fit the contraption into the proposed cinematic adaptation of Neil Gaiman's Sandman series.
 * One of the rejected designs for Doctor Who : The Movie was a spider Dalek that would unfold its side casing into eight legs. Great, now even stairs won't stop them . Spider Daleks made it into at least one of the novels, both in Dalek-sized and tank-sized varieties.
 * Comic Book: The Movie: Kevin Smith relates (based on his experience with Superman Returns above) how the director of the movie Hammill's character is making a featurette on (with the ulterior motive to gain control of the production to prevent Adaptation Displacement) wanted him to write a scene where the hero fights a giant mechanical spider. At the turning point of the film

Literature

 * The War Against the Chtorr sci-fi novels has four metre high Vigilante-class military spiders. Unfortunately they're not that smart, which causes the hero any number of problems.
 * Richard Morgan's novels Altered Carbon and Broken Angels don't feature Spider Tanks directly, but they are mentioned by various characters. They (and various other robotic war-machines) finally make an appearance in Woken Furies.
 * In the Star Wars Jedi Academy trilogy, a group of Imperial loyalists breaks out the MT-AT (Mountainous Terrain Armored Transport), an eight-legged spider-tank designed for high and rough terrain. Each leg has its own laser cannon.
 * The Land Frigates from Leviathan. A Scorpion Tank belonging to the Ottomans shows up in the sequel, Behemoth.
 * Within the Leviathan series, most motorized vehicles use legs instead of wheels on the assumption that they are either more efficient, powerful, or adaptable. In truth, the sheer complexity of a walking vehicle would would have a staggering cost and inefficiency compared to wheels.
 * At one point in the first volume, Alek considers alternative propulsion and immediately rejects tracks as being fit only for peasant tractors.
 * The Dinotopia prequel has spider-like strutters. Unlike most other examples, they actually have flat, padded feet.

Tabletop Games

 * The Chaos faction of Warhammer 40000 loves this trope. There's the Defiler (demon possessed mech with four legs and two clawed arms), the Brass Scorpion, a giant mechanical demonic scorpion used by the forces of Khorne, and the Soul Grinder, which is basically a demon bolted onto a Defiler's legs. Also note the new "Blood Slaughterer". The 5th edition Necrons Codex also introduced the Triarch Stalker, although it's only six legged
 * Rifts has both Spider and Scorpion Skull-Walkers for the Coalition States, and the Bug and Land Crab APCs for the New German Republic.
 * Dungeons and Dragons has a barrel in which a person can hide himself. Multiple levers allow one to turn the barrel into a Spider Tank (complete with flamethrowers) and control it.
 * That would be the Apparatus of Kwalish. which was a standard magical item in 1E and became an artifact by 3E. It was actually primarily an underwater submarine (lobster), complete with glowing "eyes" with continual light cast on them and retractable claws in the front.
 * It returns as a standard (if expensive) magic item in 4th edition.
 * Featured in Nodwick: "Behold the wrath of Gygax!"
 * Lolth uses a giant version of one of these as her headquarters in the adventure Queen of the Demonweb Pits.
 * In the Spelljammer setting, the neogi use arachnid-shaped spaceships, some of which are well-armored enough to rate as spacegoing Spider Tanks.
 * Four-legged ('quad') BattleMechs are a distinct minority in the BattleTech universe (starting with the ones from Dougram mentioned above), but they do exist. Their main in-game drawbacks are their lack of arms and more rigid firing arcs (partly due to lack of a twistable upper torso) -- in particular, the construction rules don't allow for weapons covering their side arcs at all, thus creating significant blind spots. On the plus side, they get minor maneuvering benefits and are less likely to fall down as long as all legs are still working.
 * The Phyrexian Walker from Magic: The Gathering.
 * Ditto with the Hedron Rover, which is apparently a Spider Tank made out of rock.
 * GURPS Ultratech has the Exo-Spider.
 * Though not strictly tanks, the Leviathan and Harrower helljacks from Warmachine qualify well enough for this trope.
 * The Cygnar Battle Engine the Storm Strider, can also count its a four legged machine that blasts its targets with lightning.
 * The MTV in the sample adventure for Paranoia second edition. Perhaps unique in being based on a submarine with legs bolted in place. (Incidentally, the manual control system consists of six joysticks, and is about as reliable and intuitive as learning to play the piano with your knees)
 * You doubt the efficiency of Friend Computers creations? Please report to the nearest termination booth, on charges of Treason. Have a nice day, citizen. Happiness is mandatory.
 * Dystopian Wars loves this - not only do the Empire of the Blazing Sun have one (the Taka-Ishi Heavy Walker), but the Covenant of Antrartica's small and medium tanks are quadroped walkers as well. Their Landship however is far from a Spider, but also worthy of inclusion here.

Toys

 * The Swamp Strider and Skopio XV-1 from Bionicle. The latter was also capable of transforming into a regular tank, but with pincers in place of a turret.

Video Games

 * The United Civilized States "Spider", the only six-legged vehicle in Earth 2150, is an excellent example of this trope.
 * Super C had the "Babalu Destructoid Mechanism", the Mini Boss of the third stage. It doesn't have the planet-destroying power that was stated in the manual, thankfully.
 * It returns in the first stage of Contra: Shattered Soldier.
 * Scarabs in the Halo series.
 * And a special variant in Halo Wars, Super Scarab!
 * Don't forget the Scarab's little brother Locust from Halo Wars.
 * In Starcraft, most of the Protoss ground mechanical units are some variation on the Spider Tank. These include the Dragoon, the Immortal and Stalker (upgraded dragoons), and the Colossus. (The sole exception - the Reaver - moves like a mechanical caterpillar rather than a spider.)
 * The Colossus isn't a spider tank so much as it's a 4 legged tripod. The War of the Worlds influence is very obvious when you think about it.
 * Arm's Spider and Invader, and Core's Roach from Total Annihilation. The Spider actually has spider neurons in it's brain to coordinate the 8 legs.
 * Shadow Complex has you fight these several different times as minibosses or (during the final boss fight) as as regular enemies. In one such fight you can't even damage the Spider Tank, as it's clinging to the wall high above you (beyond grenade range, and it's bullet-proof)--you have to trick it into repeatedly bursting water mains until it can't climb any higher above the rising flood, causing the tank to become the toaster in a huge Electrified Bathtub.
 * Countless units from Supreme Commander including the Aeon's Harbinger and Sprite Striker. The Cybran have many such units, including The Mantis, The Fire Beetle and The Brick. Two of the Cybran experimental units qualify: The Monkeylord Experimental Spiderbot; and the Megalith: Experimental Megabot (see picture). The Cybran's Tech 2 Destroyer transforms into a giant spider tank to walk on land.
 * Even more bizarrely, one of the Cybran Spider Tanks is a mobile factory that lays eggs which hatch into units.
 * In the sequel, nearly all Cybran land units are spider tanks, and all naval units (barring the giant squid submarine) can become spider-boats and walk on land.
 * The UEF, Aeon and Cybran unit design philosophies are basically "Tanks", "Hover Tanks" and "Spider Tanks" respectively.
 * The soviet Sickle Tank from Red Alert 3 and its predecessor the Reaper
 * The soviet Stingrays become this when they move from sea to land.
 * Red Alert 2 has the Terror Drone, which is a small machine that kills infantry in one hit, and takes down tanks in seconds. And is very bloody fast. It returns in RA3. But now it swims.
 * 4 Tiberian Twilight actually has a tank called the Spider Tank, which is a small tank which fires a laser, and can burrow into the ground to move around unseen. It even creates a laser "web" when in close proximity to other Spider tanks, which damages units which get caught in the web.
 * Kane's Wrath introduces the Eradicator Hexapod. Granted, it's missing a pair of legs, but still it's gigantic freakin' bug. Also, the scrin have the gun walker, a much weaker and smaller Spider Tank.
 * Don't forget Nod's Redeemer 'mech! It qualifies as a Spider Tank too.
 * Eric Gooch, who did 3D modeling for the Command and Conquer series (in addition to playing Seth in the first game), also did this.
 * The Clock/Punk Vinci faction in Rise of Legends have Clockwork Spiders. They also have the Land Leviathan, which is essentially a steam-powered clockwork missile-launching subterranean Scorpion Tank the size of a small city.
 * Spider Drones show up as Mooks early on in Xenosaga.
 * 4-Leg AFW's in Ring Of Red.
 * In his boss appearances in Earthbound, Mother 3 and Super Smash Bros Brawl, Porky Minch favours these as his weapon/vehicle/way-of-not-dying-messily of choice. It's effective, to say the least.
 * Quadraxis in Metroid Prime 2.
 * As well as the Quads in general, all of whicch are able to separate into a head and a body.
 * Mega Man X8 has a huge crab-like Mechaniloid as the boss of the opening stage.
 * The Guard Scorpion from Final Fantasy VII.
 * Final Fantasy VIII had X-ATM092, a spidery robot who couldn't be beaten down and which had to be run away from, kind of an implacable spidery robot, of course it gets shot to pieces later on, despite 30 random battles with it won't put it down.
 * It could be beaten if you killed it on the bridge and abused its weakness to thunder.
 * Now set to the theme from Wild Wild West!
 * Crisis Core adds a Guard Spider.
 * Let's not forget the superboss Omega from Final Fantasy V
 * Which has gone on to appear in a half-dozen other games with the same basic form
 * Starsiege
 * In Star Ocean: Till the End of Time, one of the enemies in Moon Base are spider mechs. And they are also Demonic Spiders, due to their very deadly attacks. They also occupy a huge portion of walkable space, so it's very hard to avoid fighting them.
 * Mechwarrior 2 has a bonus mech, appropriately named "Tarantula", that fits this. It's a bit of a hack, in that the engine isn't natively capable of handling four-legged mechs, so the fore legs of the Tarantula are actually its arms. Which can cause bizarre damage effects: shoot off one of the hind legs and you get a three-legged Tarantula unable to move, but shoot both fore legs and it'll still cheerfully hop about on just the hind ones. And if you shoot off both fore legs and one hind leg, it'll stay there suspended and unmoving on... one leg.
 * Deus Ex has both the small, annoying kind, and the absolutely huge, terrifying kind. Both shoot electricity that, on top of inflicting actual damage, also drains the energy you use for your augmentations.
 * Arachnos in City of Heroes is a villain group that is all things spiders and so they developers couldn't pass up an opportunity to put in anatomically correct (8-legged) spider-bots of all sizes. Players in City of Villains can summon them if they have the Bane Spider or Mace Mastery power sets.
 * The best one qualifying for this trope though has to be the Arachnos Heavy, the biggest and baddest spider-bot of them all that's the size of a tank.
 * Even bigger than the Arachnos Heavy is the Jade Spider, originally just a plot device from the comic, now a monster in it's own right. And it's psychic.
 * The Landstalker from Ratchet and Clank: Deadlocked is a 4-legged Player Vehicle variety.
 * The Dark Terraformer in it's mobile stage from Jak 3, as well as the Krimzon Blast Bots.
 * The Arachnotrons and the Spider Mastermind from the Doom series are essentially demonic spiders (not to be confused with the other variety) with mechanical lower halves with four legs and either a plasmagun (for the Arachnotrons) or a super-chaingun (for the Spider Mastermind). Though they are actually giant brains (with faces) atop mechanical spider-legged platforms.
 * The first PlayStation 2 Transformers game (the good, non-movie one) has non-transforming spider tanks as a regular enemy. They have three legs, and are pretty dangerous, having powerful (but easily dodged) weapons and no weak points.
 * Dr. Eggman uses a number of machines like this (the Egg Dealer from Shadow the Hedgehog immediately comes to mind).
 * The Hierarchy in Universe At War: Earth Assault use a lot of Spider Tanks. in fact, their bases are giant Spider Tanks.
 * "Enemy Walking Tank: SPIDER."
 * The small spider droids from Attack of the Clones show up as mini-bosses in Star Wars: Republic Commando.
 * Gnomes sometimes use small steampunk-versions of these in the Warcraft setting.
 * A giant mechanical spider featured in Metal Wolf Chaos, which was eventually defeated by the President's giant robot picking it up and throwing it into the horizon shooting it full of holes.
 * Gecko Sub Boss from Einhander.
 * The Neotank from the Advance Wars series is a spider-shaped tank and the second most powerful land unit in the series, after the Megatank. With wheels on its feet, it is also the fastest tank in the game, offering it a significant advantage over the Megatank.
 * Para World has a Bamboo Technology version of the scorpion tank variant. It's a close-combat machine that can also harvest resources. There is also, later, a Steampunk spider tank.
 * Quake IV has the cyborg-zombie enemy, the Strogg, strongly favor the spider tank design. Stream Protectors, Harvesters, and the Makron itself all go around on spidery legs despite the existence of floaty technology, which you'd think would be better.
 * Actually, once the Makron's legs are damaged at the end of the game, it's upper body starts hovering. Also the Quake II Makron used a spider tank (Jorg) in the opening of that game's final fight, only to start using his own two legs once you take the tank down.
 * Having only 2 legs and being og humaoid shape, the Jorg is not a Spider Tank at all, but rather an exoskeleton.
 * The harvesters are actually techno-organic, as indicated by their shrieking sound.
 * Wasteland: Honorable mention goes to the dreaded Scorpitron. Of course at least in the original game it's basically depicted as an Ogre with a scorpion tail attached so it doesn't quite fit into the trope smoothly.
 * Warlords Battlecry 2 has the Dark Dwarf's Firebombs, small (and, again, fast) eight-legged machines that suicide when attacked or when they attack.
 * Unreal Tournament III has the Scavenger, a four-legged tank that can transform into a high-speed ball. Also, the Darkwalker.
 * Armored Core: Quad-legged mechs have been an staple since the beginning. They are surprisingly fast bastards, despite often having a high weight. I site Red Rum, of 4A as proof of how fast these fuckers can be (not to mention how difficult the series can get) the only thing that keeps them from being perfect is the high energy requirements.
 * Fallout: Tactics has a Scurry Robot. They weren't made for battle, but ended up used as makeshift Goddamned Bats, and they can bury themselves for an ambush. Their Walking Tank brothers are much bigger and meaner.
 * Thunder Force V has Armed Armament Arm (A3), a spider mech that transforms into a land vehicle,then an aerial robot when damaged enough the first two times. After the third time, its gone for good. The sequel had Barbaric Berserk Beast, an obvious Expy of the above mentioned.
 * The steampunky Arcanum has mechanical spiders of a highly realistic 8-legged sort, which you can find in a hostile rips-you-apart disposition or build yourself in a rips-other-people-apart disposition. A variant of the chassis comes with a healing kit instead of rending mandibles.
 * Lost Planet: Extreme Condition has the GAB-25 Vital Suit which can transform between this and Drill Tank modes.
 * An even larger version of the GAB-25 serves as a boss enemy in one of the later levels, and Lost Planet 2 takes it one step farther by making it gattai with the GAN-34 for a boss fight. The feat can be reproduced in both the campaign and multiplayer modes by two players, and doing so nets you an achievement and a title called "And I'll Form the Head!" However, when used by the players, the resulting machine is more of a traditional tank, unlike the boss.
 * The final boss of TimeShift is one of these. Disappointly, you fight it from a rooftop across the street instead of in a cool freeform on-foot battle.
 * Turok : A Spider Tank is a boss in the 2008 Continuity Reboot game.
 * In Metal Gear Solid Portable Ops, a variation of the Metal Gear (known as the RAXA, and its mass-production model, the ICBMG) uses four legs instead of the usual two, possibly invoking this trope.
 * The Iron Grip series features several of these, including the Fahrong Confederation's Recluse, Warweaver and Widow "arachs". The Widow is quite literally a gigantic self-propelled artillery piece.
 * The Playstation port of Time Crisis featured an infantry fighting vehicle modified with legs instead of wheels on its 'Kantaris Deal' side story, as the boss of the slowest possible route.
 * The Playstation 2 game Steambot Chronicles features spider legs as a potential upgrade to the player's bot.
 * In Crimson Skies: High Road To Revenge, one of Die Spinne's superweapons is a giant, six-legged machine armed with a massive flamethrower.
 * House Atreides' Minotaur from Emperor: Battle for Dune.
 * Razing Storm pits you against one of these in the third stage. It's really persistent, and it uses a Macross Missile Massacre when defeated in a last ditch attempt to destroy your characters.
 * Metal Fatigue has the murderously powerful scorpion tanks as part of the precursor arsenal. Most tanks and other ground vehicles are little more than fodder in the face of Combots, even poorly-equipped ones. A squad or platoon of Hedoth scorpion tanks can handily put a serious dent in an equivalent number of Combots.
 * Both Spyder Scout and Viper the Sniper in Robocalypse are these but they're the humanoid size type, not the massive type.At least Viper makes up for it by dropping anvils on the enemy.
 * Morrowind: Dwemer Centurion Spider is a small version of this.
 * Raiden II : The first boss battle is against a duo of four-legged spider tanks while the first boss of Raiden IV is a single, six-legged tank instead. However, the twin spider tanks return in that game's fourth stage.
 * Metagross of Pokémon seems to've been based off of this.
 * Though that can bloody fly as well.
 * Battle Clash: Antonov's Standing Tank Ivan, minus the mobility part.
 *  Front Mission features several enemy Commander mechs of the sort, which can be obtained by completing special missions and completing the game.
 * Spider Mechanoids from ''Serious Sam II'.
 * Cobar's spider tank from Killzone: Liberation also spawned smaller spiderbots.
 * Ray Storm's first boss transforms between a large tank and a spider walker. Another spider tank in the series is Pro-Tor from Ray Crisis.
 * Mass Effect 3 shows that Reapers can take this shape for moving on land, compared to the more cuttlefish / squid-like shape they use when flying.
 * Three Variant Armor from Cyberbots use 4-insectoid legs - Jackal, Cyclone and Talantula.
 * In Jeff Wayne's War of the Worlds, the Martians expand on their machines' number of legs, resulting in this.
 * One of the bosses in Seek and Destroy
 * The Gradius series has the Shadow Dancer and variations in most of its final or penultimate stages, and in the third stage of V. In many of its appearances, it is invincible and can only be dodged as it passes.
 * Stalkers from Resistance.
 * The second form of P.N.03's final boss somewhat resembles a scorpion. The first boss and some of the mooks are also spider-like.
 * The SNES game Metal Warriors had one of these hidden in the first level; it could throw energy webs, use its head...thing...as a melee weapon, and climb on ceilings and walls.
 * Battle Engine Aquila has these for both armies. The Aquilla itself is also a Transforming Mecha
 * Machines Wired for War has military and nonmilitary variants; the four-legged Reaper, six-legged Commandant, and the helpless crab-walking six-legged Locator.

Webcomics

 * Used in Girl Genius - "war stompers" of the Knights of Jove.
 * In Homestuck, as part of its extensive array of patterns and themes, each central character has some sort of futuristic vehicle connected to one of their personal motifs-- for instance, Rose's struggles with her alcoholic mother are reflected by a rocket made to look like a champagne cork. The vehicle corresponding to Cancer-themed troll Karkat is naturally one of these.

Western Animation

 * Shadow Raiders: Planet Ice's Spider Tanks (They're called exactly that).
 * Transformers: A small number of Transformers turn into giant spiders, either mechanical or organic. Tarantulas is the first and most unnerving, and his personality goes far beyond vague malevolence right on into psychosis. Scorponok in both his G1, Energon and Movie incarnations. He's closer to Tank/Scorpion hybrid than most.
 * Shockwave from Transformers Animated normally turns into a tank, but as, he actually turns into a spider crane
 * Jonny Quest: A memorable one appears in the episode "The Robot Spy".
 * The Venture Brothers: Parodies Jonny Quest's Spider Tank with Dr. Venture's obsession over his father's Walking Eye.
 * The MOGURA in Skyland is a large spider-shaped robot that was created to drill for water on an ice-covered block. Once the water ran out, though, it needed to find more sources. As it happens, humans are largely water...
 * The Spider-Slayers from the '90s Spider-Man (a black widow, a tarantula and a scorpion) doubled up as Combining Mecha.
 * While the Tarantula and Scorpion models, as well as the combination, were probably unique to the animated series, the Black Widow model Spider-Slayer had its origin in the comics.
 * None of them was original to the series. There have been a lot of Spider-Slayer designs in the comics.
 * Wolverine and the X-Men: The first Sentinel prototype was of a spider/scorpion form. It had some kinks to work out, like not knowing how to avoid collateral damage, and not having an off-switch.
 * In the 3rd episode of Chip 'n Dale Rescue Rangers, while Chip, Dale, Monterey Jack and Zipper look for Geegaw Hackwrench in an abandoned airplane, they manage to trigger traps that were set, and run into a spider-like mecha, which turns out to have Gadget inside, who comes out to greet Monterey.
 * The Decapodians "Mobile Opression Palace" from Futurama. For just pennies a day!
 * Vertex and Vett of Rollbots are sentient versions.
 * Near the middle of Beauty and the Beast, the Beast puts Maurice inside one of these which takes him back the village he and Belle live in so that his daughter can take his place as the Beast's "prisoner."
 * One of the mutant toys in Toy Story is a toy car with legs instead of wheels.
 * Phineas and Ferb has Professor Poofenplotz's "Me-Mobile" from "Isabella and the Temple of Sap", a giant version of her head mounted on spider legs.
 * Star Wars: The Clone Wars has the Umbaran juggernaut.
 * In Young Justice, the have "mechs" that are Spider Tanks in all but name.

Real Life

 * Actual vehicles have been built that use the motor configuration of arachnids. However, they move much slower than just using wheels.
 * Big Dog (from Boston Dynamics) may not be a vehicle, but just you wait. LS3 The in progress bigger brother.

However cool legged machines may be, there are several disadvantages. Maintenance is a major concern, and walking tanks are pretty much guaranteed to have at least 16 high-stress (hip lateral, hip vertical, knee, ankle, multiplied by at least 4 legs) compared to 4 for tanks (just the drive wheels, an M1 could almost certainly get by without a few of its road wheels given normal ground pressure of ~15 psi). That's only for cargo walkers as well, actual combat walkers (as actually fit the trope) have to factor in armour, recoil, speed, etc. most of which count against walkers.

All of this plus the touched on, but not explicitly mentioned ground pressure issue. A tank spreads its massive weight over a pair of equally massive treads resulting in ground pressure per unit of area no higher then a walking man. An armored walker of the same weight balancing on four much smaller pads would have massively higher ground pressure and could easily bog down in any sort of soft ground (ironically much like a wheeled vehicle). You could of course try to sort of counter this by making the feet huge like snowshoes, but this would be a weak work around and could make walking unwieldy to say the least. Or you could have extra "stability" legs that are used specifically at rest or when stability is needed, and leave them retracted on the move - like on  some  cranes and artillery pieces. It's a solution for self-propelled artillery rather than tanks, though.
 * Speaking of walking on soft ground...the Timberjack hexapod deforester which can walk on uneven ground effectively (albeit has very slow turning) is proudly claiming that its feet cause less damage to ground when compare to a normal caterpillar. What kind of magic it use? Rubber dampers.
 * And that's why the cheap robots they're designing to wander Mars are called 'spider-bots'. They only have six legs, though. And they're kinda small. And there will be a lot of them. They're cheap, after all.
 * The Kabutom RX-03, which took 11 years to build, is 11 meters long, 9.5 meters wide, weighs 15 tonnes and carries up to 6 people.
 * La Princesse is a giant mechanical spider, but it's supported by a crane. The legs are just for show.
 * A bunch of people at the University of Louisiana created the Cajun Crawler, which is basically a Segway only with little legs (based off of Theo Jansen's Strandbeests) instead of wheels. The result is one part Nightmare Fuel, and two parts awesome.
 * This is not Photoshopped, but it is just a statue.
 * NASA's Athlete project probably applies. They're six-limbed robots with wheels on the end of each limb, giving them the ability to walk or roll depending on the situation. The end goal of the project is to create a robot to carry cargo on the Moon.
 * Mondo Spider. See also on YouTube. So far, it didn't surpass human walking speed, but yes, it turns on the spot. "1,700 lbs of Mechanical Mayhem" is moved by hydraulics powered with 12hp average (30hp peak) worth of electrical motors.