Solidus Snake was Raiden's main antagonist in the Big Shell chapter of Metal Gear Solid 2: Sons of Liberty. In the game, he was revealed to be the third and final clone created from Big Boss as part of the Les Enfant Terribles project which was engineered by the Patriots. Solidus was described as a pure clone of his father - as his DNA pattern exactly matches Big Boss (unlike his genetic brothers) and he was the sole purpose of the project, created by the Patriots to be their perfect weapon.
Solidus became a skilled soldier and during his participation in the Liberian civil war of the 1980's he would routinely kidnap orphaned children and train them to become deadly child warriors as part of his "Small boys unit". One of the children who became involved with Solidus was Jack, who would later be codenamed Raiden. Solidus - secretly responsible for the murder of Jack's parents - took the young boy under his wing and trained him to become the leader of his unit. As with many of the children, Jack would look up to Solidus as a sort of father figure and would follow his orders without question.
Metal Gear Solid
He went on to become the 43rd president of the United States, going by the name George Sears. Working on his own, he decided to create an "incident" on Shadow Moses as a way to gain entry to the Patriots organization as member of the wise man's committee. He wanted to blackmail them with Metal Gear Rex. To do this, he used one of their agents, Revolver Ocelot, to incite Liquid Snake into revolting and capturing Shadow Moses with the next generation special forces and then have Ocelot manipulate Liquid's actions. The Patriots countered his plan by using Solid Snake as a vector for the FOXDIE virus and leave Metal Gear Rex undamaged for retrieval. When Snake was successful in his mission, the Secretary of Defense Jim Houseman took the fall for Solidus. He and Ocelot then went into hiding and make contact with Sergi Gurlukovich and his private army of Russian mercenaries, as well as the rogue anti-terrorist agency Dead Cell which Solidus had set up as George Sears. They also made preparations for another uprising against the Patriots four years later at the Big Shell with purpose of capturing Arsenal Gear.
Metal Gear Solid 2
After he resigned as President of the United States, Solidus Snake formed a terrorist group and recruited the Presidential anti-terrorist unit Dead Cell - he called the group "the Sons of Liberty". Their goal was to take over an off-shore purification facility known as the Big Shell, which was actually being used as the secret development site of a giant Metal Gear called Arsenal Gear . This new Metal Gear was being designed by the Patriots to be capable of controlling the flow of information on a global scale. Solidus's ultimate aim was to gain from Arsenal Gear the true identity of the Patriots and bring their evil reign to an end.
When he kidnapped the new US President and demanded a ransom of 30 billion dollars, the US government sent his protege Raiden to try and stop him. In his encounters with Raiden, Solidus lost one of his eyes and he began wearing an eye patch, making him look like his father Big Boss. He also wore a suit equipped with artificial muscle which used reflex action to dissipate any and all damage while increasing his reaction times. Solidus's plans were halted when Raiden uploaded a worm cluster into the mainframe of the Arsenal Gear system wiping out all the information it once carried.
By detonating the pure hydrogen bomb carried aboard Arsenal Gear in the atmosphere above Manhattan, he planned to destroy all electronic devices, bringing Wall Street to a halt and spurring the world into a panic. He would then free Manhattan from its digital yoke and establish a liberated zone in its place called Outer Heaven (once the dream of Big Boss). When he failed and discovered that Revolver Ocelot was an agent for the Patriots, and that Raiden was also being manipulated by them this forced Solidus's back against the wall. In a final move of desperation he crashed Arsenal Gear into New York City's Federal Hall in an attempt the strike back at the Patriots. In a final battle with Raiden, he revealed that he wanted to use the nanomachines as a plan B to discover the Patriot's identities. This final sword duel on the roof of Federal Hall resulted in Solidus's defeat when he was thrown from the top of the the building.
Metal Gear Solid 4
Solidus's remains were retrieved by the Patriots but were then stolen by EVA and her underground group. His body was used as spare parts for transplant surgery on Big Boss and his head and chest were used to create a dummy version of Big Boss's corpse. In 2014, at the beginning of the Guns of the Patriots conflict, those remains were lost in the boat fuel fire sparked by a gunshot from Liquid Ocelot.