While RAY has a pair of Gatling guns and missile launchers on its back and knees to defend itself from more conventional battlefield threats, its primary weapon is a powerful water jet cutter, which can cut through heavily armored foes, such as Metal Gear derivatives. RAY is more organic in appearance and in function than previous models. Its streamlined shape helps to deflect enemy fire and allows for greater maneuverability both on land and in water. Its interior workings are also somewhat organic, as it has artificial fibers that contract when electricity is applied, much like natural muscle, instead of typical hydraulics; this pseudo-muscle tissue makes it very maneuverable. It also has a nervous-system-like network of conductive nanotubes, which connect the widely dispersed sensor systems and relay commands from the cockpit to the various parts of RAY's body, automatically bypassing damaged systems and rerouting to auxiliary systems when needed. Another feature is its blood-like armor-repair nanopaste, which is secreted from valves and coagulates wherever the exterior surface is damaged. Particularly unusual is its "face", with two "eyes" and a gaping "mouth", only seen when the head armor is removed. The original version is an operational prototype labeled "MARINES", which has a cockpit for a single pilot, and a long tail intended for balance while making leaps or operating underwater. The entire forward interior of the cockpit is a heads-up display, allowing the pilot to look around as if there were no obstruction between him and the battlefield. The mass-production model labeled "U.S. NAVY" lacks the tail of the prototype, but it has rounded knees and only one sensory input or "eye" instead of the prototype's two. They are also painted in an olive-drab camouflage pattern. During the Tanker chapter (the prologue of Metal Gear Solid 2), Revolver Ocelot steals Metal Gear RAY off the disguised oil tanker and delivers the stolen prototype to The Patriots, an organization secretly running the United States. During the Plant chapter (the second part of Metal Gear Solid 2), Arsenal Gear has a force of unmanned mass-produced Metal Gear RAYs ready for immediate deployment against any possible threats under the command of the ship's AI GW. When Solidus Snake takes over Arsenal along with the slave RAYs, Solidus has them confront Raiden but some of them end up destroyed. In Metal Gear Solid 4: Guns of the Patriots, Liquid Ocelot pilots a modified version of