Liquid Snake or simply Liquid is first introduced in Metal Gear Solid by Colonel Campbell during a special Mission briefing prologue. He is explained as being the squad commander of the Special forces unit Code named "Fox Hound". As well as sharing the same code name as the series protagonist Solid Snake. Liquid was born in 1972 as a result of a top secret black ops project initiated by the patriots known as "Les Enfant Teribles". They're several goals for the project.One was to help identify something referred to by Liquid as soldier genes, which are coined as traits that are accountable for instinctual survival tactics that some soldiers are born with. Second, the project aimed at circumventing training by injecting mercenaries with "solider genes" Genome soldiers are an example of this process. Lastly the project was intended to genitically engineer the genes of big boss and create the greatest solider in history. Three clones survived the process Liquid, Solid, & Solidus Snake. Liquid Snake was engineered to have Big Boss's dominant traits. Solid Snake was given the recessive traits while Solidus was meant to be a perfect clone.
Shortly after birth, Liquid is sent off to the United Kingdom where he eventually joins the S.A.S.where is skyrockets up the ranks. Even at a extremely young age Liquid Snake was skilled enough to become a par of the Secret Intelligence Service during the Persian gulf war and carried out many undercover missions. Liquid's real name is so heavily classified it is said that even the highest levels of military dont have clearance.Like his clone brothers, Liquid Snake posses a genius level 180 I.Q and is fluent in several different languages.
During the events between Metal Gear 2 and Metal Gear Solid. It is presumed that Liquid finds out about his origin & somewhere within that time was given the impression that he was the one who was given the inferior genes of Big Boss. Its not clear how he obtained this misinformation, but it sets Liquid down the path of revenge. He sets out on a plan to retrieve the remains of Big Boss & to defeat his "brother" Solid Snake.
Despite Liquid Snake being one of the "sons of Big Boss" he hardly shares any aesthetic traits with his kinship. He has long blond hair and a medium skin tone. He is about 6' 2" with an athletic build. He is usually seen with a Brown jacket and pants. He has also been known to wear sunglasses and gloves.
Liquid's powers come from his lineage he is a clone of Big Boss which means that most of his combat skills were acquired at birth. He is an expert marksman, posses an IQ of 180, speaks several languages,and his CQC skills are among the best in the world. He is also a charismatic leader, and is known for being extremely manipulative. He can pose as other people easily. Lastly, he can pilot both Rex and Ray Models of Metal Gear.
Like Solid Snake, Liquid Snake is a master at the many and varied arts of war. This is hardly surprising, as Liquid and Solid are two sides of the same coin: they are clones.
There the resemblance ends. Unlike Solid Snake, Liquid was raised in Great Britain, undergoing rigorous training as he grew. Liquid's hunger for battle was voracious, and he became a combatant as a prepubescent. His mastery of several languages, chief among them Arabic, allowed him to effectively function as an assassin for many years.
Liquid was eventually captured by Iraqi forces, who brainwashed him into performing missions for them. This lasted until Solid Snake left Foxhound, a unit that was much admired by Liquid. Liquid joined and quickly became team leader. His true nature soon surfaced, and he cut ties with the U.S. government shortly before seizing Shadow Moses Island. He gets killed by his brother because of the virus that was injected in him gave certain people heart attacks.
After he dies Revolver Ocelot finds Liquid and for some reason attaches Liquid's arm and his own to make up for the loss of his during his fight with Gray Fox. He somehow takes possession of the arm from time to time and controls Ocelot against his will.
Sons of LibertySometime later Ocelot uses his russian forces to invade a United States Marines boat as they are demonstrating their newest weapon Metal Gear Ray. His forces quickly take over the boat and he personally kills its commander. After this he sees Solid Snake trying to destroy the Metal Gear and Ocelot then gets possessed and tries to kill Snake and almost drowns him destroying the ship.
Solid SnakeHis brother and sworn enemy. Liquid originally thought that Solid Snake had recieved the dominant genes when in fact he had but it didn't matter as Snake proved time and time again to be the better sibling.