This article will look at the various other Metal Gear mechas throughout the video game series.
The RAXA and the ICBG Metal Gears appear in the “Portable Ops” video game featuring the original Snake/Big Boss=built by Sokolov, who somehow survived “Snake Eater”. The games sort of occupy an ambiguous point in the Metal Gear timeline, with Kojima stating some events happened, some didn’t. Since Snake/Big Boss seems surprised in Peace Walker that a Metal Gear-like design is being developed (The Basilisk, or “Peace Walker”), I’m guessing these two aren’t really considered a major part of the timeline.
The Walker Gear appears in Metal Gear Solid V:The Phantom Pain. This is a smaller, manned model (Although it can also function independently.). Although a main, mass-produced version is used by XOF/Cipher and their associated allies, Huey Emmerich soon designs another model for Venom Snake/Big Boss and Diamond Dogs-that can also be customized and loaded with a variety of different weapons and modes.
D-Walker also has a big brother Huey develops exclusively for D-Dogs, called “Battle Gear”. However, this particular derivative-which is more a hover-tank than a walking one, hence not a true “Metal Gear”-is not really utilized in the game, except in deployment missions in which you assign D-Dog mercs to help with various causes.
The same principles for Walker Gear and Battle Gear would later be utilized with Metal Gear Gustav, a slimmed-down version of Metal Gear G used by the more villainous Big Boss in Zanzibar Land. Although they don’t appear in the release version of Metal Gear II.
The Metal Gear II (in game) was in the ‘alternate’ Metal Gear sequel, Snake’s Revenge, for the NES. It’s developed alongside mass-produced versions of the TX-55.
The Gekko, or IRVING, is a small design using an AI, and developed using inspiration from REX (The head) and RAY (For the legs). It also makes bizarre, cow-like noises, and possesses some organic components as well. In addition to being a pain for Solid Snake, they also often confront his ally Raiden (pictured), in both MGS4 and Metal Gear Rising: Revengeance.
There’s also the creepy-looking smaller model, the Dwarf Gekko.
Also in IV, we’ve got the cute Metal Gear Mk. II. This tiny robot serves as a sort of camera allowing Snake’s friend Otacon to analyze and help Snake during the game. Superficially, it’s body resembles TX-55, except with it’s larger relative’s nuclear payload replaced with a small flip video screen.
It’s later destroyed by Ocelot’s forces, but it provides vital Intel before doing so.
It’s later replaced by a Mark III model.
Interestingly, the Mk II actually debuts in an older game, Kojima’s Blade-runner inspired adventure game SNATCHER (Developed shortly after the original MG came out). Given that it’s set in the future, and Metal Gears are mentioned as having existed in the past half-jokingly, this is sort of a future Mark from the last two. (Whether Snatcher is in any form of MG continuity though, who knows?)
Raiden also gets to confront his very own Metal Gear nemesis, the anti-cyborg EXCELISUS, in addition to the RAY and GEKKOS, in Metal Gear Rising.
Metal Gear GANDER appears in Metal Gear Solid: Ghost Babel, a game boy game which served as an alternate sequel to the original Metal Gear, and a different take on “Solid”‘s story. Like it’s ‘canon’ counterpart REX, it is stolen and used by the villains.
Finally, we have the KODOQUE and CHIDAOTH, both from Metal Gear Acid, the somewhat more goofy, non-canon, more card-based games for the PSP. They’re considerably more colorful than your average Metal Gears.