unconscious. However, it also runs on batteries which deplete while in operation. The Mk. II is automated in the game, but can be controlled by the player if needed. The Mk. II is destroyed after the Eastern Europe mission and replaced by the Metal Gear Mk. III, a similar design which accompanies Snake at Shadow Moses and Outer Haven. The Mk. III has the same body as the Mk. II, but with a red-colored exterior, and serves the same function. Peace Walker Peace Walker is the name given to an autonomous nuclear weapons platform in Metal Gear Solid: Peace Walker. Developed in secret by disavowed CIA agent Coldman and deployed to Costa Rica in 1974, Peace Walker was designed to prove that nuclear deterrence is a myth by objectively and logically assessing the threat of a nuclear exchange and retaliating in kind. Peace Walker is quadrupedal in form, with a spherical radome "head" and a cylindrical AI core functioning as its brain. It is designed to be fully self-supporting, with an array of anti-personnel weapons used to defend itself, and a protocol that calls for it to recognise and eliminate all threats to itself before launching its nuclear missile. Peace Walker is supported by four autonomous weapons that the player fights throughout the game: Pupa (GW-PUPA 5000), a larger version of the Shagohod that has had its Archimedes screws replaced by caterpillar tracks. It is designed to be fast and agile. Chrysalis (TJ-CHRYSALIS 6000), an aerial unit with VTOL capabilities. It is referred to as "El Colibri" ("the hummingbird") by the Sandinistas. Cocoon (TR-COCOON 7000), a giant land battleship lined with numerous weapons emplacements. Basilisk (AL-AURELIA 8000), a bipedal form of Peace Walker that contracts itself to make it easier to be shipped. Metal Gear ZEKE Metal Gear ZEKE is a Metal Gear built in the Militaires Sans Frontieres in Metal Gear Solid: Peace Walker. Developer Huey and MSF sub-commander Kazuhira Miller named the mech in honor of Granin's "Metal Gear" design philosophy and the Zero fighter, which was codenamed ZEKE by the Allies in World War II. The unit is also the series' second Metal Gear that the player can use in any capacity, as it can be fielded in the Outer Ops missions once all the parts have been installed. ZEKE's default armaments are a railgun mated to a radome, three machine guns, and a number of guided