Metal Gear REX is a fictional mecha in the videogame Metal Gear Solid.

History

When REX began development, weapons company Arms Tech were in a dire state financially. With talk of a hostile takeover after the failure to obtain the contract for a new line of fighter, the chief of DARPA (then Donald Anderson) was bribed heavily to back the Metal Gear REX program and fund its development covertly. During railgun testing at a nuclear weapons disposal facility on Shadow Moses Island, REX's prototype was captured by the FOXHOUND special forces group which had been assigned to protect it. The threat of a nuclear attack was used in an attempt to extort $1 billion and Big Boss's remains from the US government.

REX's chief engineer, Hal "Otacon" Emmerich, was opposed to nuclear weaponry, and it was unlikely he would have assisted in the program if he had known REX's true purpose. He was informed that REX was intended for intercepting nuclear weapons, and REX's armaments were handled by a separate department to keep him in the dark. Their development and integration into the main chassis were out of his control, and as far as he knew, these armaments were intended to defend the REX unit itself, and to provide Theatre Missile Defense .

It became clear that REX was in fact to be used to make the nuclear strike; Otacon took it as his duty as REX's creator to destroy it. It was subsequently disabled by Solid Snake with the assistance of Grey Fox and Otacon's information.

Revolver Ocelot escaped Shadow Moses with the blueprints for REX, however, and soon sold them onto the black market. As a result, REX's epigonies spread worldwide. Snake and Otacon therefore formed Philanthropy, and sabotaged as many REX development operations as they could; the USMC's response to the REX threat was to develop a new Metal Gear, a hunter-killer to eliminate REX's descendants. It was named Metal Gear RAY.

Crew

REX is shown to be operable by one individual, as Liquid Snake is able to use it quite effectively in battle against Solid Snake and Gray Fox. It is not clear if it is intended to have additional crew. The pilot has no direct view of the world outside of the cockpit; instead information is gathered by a sensor package in a radome on the left shoulder of REX, and passed on. This leads to some vulnerabilities (see below).

Weaponry and defenses

REX is equipped with two Vulcan cannons, a TMD missile module, knee-mounted anti-tank missiles, a free electron laser, and an electromagnetic railgun (although Otacon's description of its functionality is far closer to a coilgun). All were supposedly intended to defend the REX unit and intercept incoming nuclear weapons.

In fact, REX's railgun is designed to deliver a nuclear warhead. With no propellant trail or engine flares to reveal its location and trajectory, a nuclear strike could be made which would be impossible to intercept or to trace back to its origin. Combined with REX's high mobility, it represents an incredible threat; in Otacon's own words, "this thing could mean the end of the world".

REX's armour is all but impregnable; however, the lone pilot is completely dependent on a radome mounted on REX's left shoulder to provide information about the outside world. If the radome is destroyed, REX immediately opens the pilot's compartment; not only is the pilot then dependent on their own eyesight to acquire and attack targets, but they are vulnerable to weapons fire (for example, stinger missiles). The legs has also been greatly fortified compared to the previous Metal Gear models (the TX-55 Metal Gear prototype and the revised Metal Gear D), which were vurnerable on their legs.

Design information

Yoji Shinkawa, the mechanical designer on the Metal Gear games since Metal Gear Solid, has commented that much of REX's design was based around technical limitations of the PlayStation system- hence the large, flat panels which make up its structure. Compare with Metal Gear RAY in MGS2.