Gear REX

Gear REX, also known as the "Nuclear Dragon," is a monster that Big Boss and the Militaires Sans Frontieres often encountered during Operation Peace Walker.

History
Gear REX was created due to mutations from nuclear test sites. Because of the mutations, Gear REX developed a protuberance resembling a gun turret, as well as a highly acidic and corrosive mucous that is capable of melting absolutely anything it comes into contact with. However, the mucous can be reverse-engineered to form a highly flexible and sticky substance. When creating the substance, its bodily fluids are turned into a purified form via filtering them, which results in it becoming incredibly concentrated. Further distillation of the filtered bodily fluids from Gear REX will increase the concentrated state to devastating levels. It is also capable of ejecting the spines on the side of its head and its roar can vibrate the spines and cause them to shatter, which is effective in stunning its prey.

Gear REX was first spotted on Isla del Monstruo, although it was presumably not native to the island, since there was no record of any nuclear tests having been carried out in the region. Sometime afterwards, a Gear REX originating from the Pacific entered Costa Rica from the South Pacific coast and traveled to Mt. Irazu, until it reached the crater's vicinity around noon the next day and stopped, destroying several houses and buildings in the process. Because Costa Rica had abolished its army after the Costa Rican Civil War, it was unable to deal with Gear REX, and thus the MSF was dispatched to stop it.file:///Users/omontiel/Desktop/gear-rex.jpg

Sometime afterwards, a Gear REX somehow managed to board the Mother Base and was causing some havoc. Because of this, the MSF had to go on the defensive and defeat Gear REX.

Trivia

 * Chico told Big Boss of a legend that Gear REX was a dinosaur that was revived as a zombie and attacked people, with Big Boss expressing disbelief in the existence of zombies. Chico counters his argument by stating that Haiti plantations had used zombies as slaves for years, and had even handed down a secret zombie powder over many generations.
 * During Operation Snake Eater, Para-Medic discussed with Big Boss the movie Godzilla and its status as an anti-nuke movie; the titular monster being symbolic of the dangers of nuclear power. Big Boss jokingly remarked that the Marshall Islands must be, "crawling with creatures like Godzillia," due to nuclear testing, similar to the origins of Gear REX itself.

Behind the scenes
Gear REX is featured in the non-canonical Monster Hunter Extra Ops in Metal Gear Solid: Peace Walker. It bears a strong physical resemblance to its namesake, Metal Gear REX, including bone ridges that make its face look like the Metal Gear, and a limb over its right shoulder representing the railgun.

Gear REX's creation, as a result of nuclear testing, resembles that of the famous Japanese movie monster Godzilla.

Despite the fact that Gear REX was created as part of a crossover between the Metal Gear Solid and Monster Hunter franchises, Gear REX's bio does not contain the latter's trademark.

Gear REX is a refrence to Metal Gear REX but the reason why there is no Metal in it is because it is not made out of metal,Common sence.

Gameplay
Defeating Gear REX with an S-rank under any of its missions will unlock the Gear REX uniform, which will allow anyone who wears it to steal PSYCHE energy from the enemy. Also, defeating Gear REX in certain missions will unlock various items pertaining to Gear REX and are vital for the development of the Human Singshot if lucky. If Gear REX is defeated in a Hunting Quest, the Gear REX Mucous might be unlocked, which will begin development on the Sling Band Rank 1. Defeating Gear REX in Gear REX: Showdown at Crater Base will sometimes unlock the Gear REX Concentrate, which will allow for the development of the Sling Band Rank 2. Finally, finishing Gear REX off at Gear REX strikes back will sometimes unlock the Gear REX Super Extract, which will unlock the Human Slingshot Band Rank 3 for development.

Gear REX Mucous
Highly acidic liquid fired out by Gear REX. Can be modified to form a poweful sticky solution.

Gear REX Concentrate
Gear REX's bodily fluids filtered to increase purity. Incredibly concentrated.

Gear REX Super Extract
A distilled version of Gear REX's filtered bodily fluids, increasing the concentration. Devastatingly concentrated.

Gear REX (Uniform)
Variation of Jungle Fatigues camouflage. Grants the wearer the ability to steal PSYCHE from enemies after grabbing them.