Liquid Sun

Liquid Sun refers to the 2014 incident in the Middle East, during which Liquid Ocelot made preparations for an armed insurrection against the Patriots.

Following the Big Shell Incident, the world had slipped towards a state of total war, with restrictions on military intervention in foreign countries easing, fuelling the need for mercenaries. The world's economy gradually changed to one of war reliance, with most world conflicts resting heavily on the use of private military companies. The five largest of these were run by a single mother company, known as Outer Heaven, headed by Liquid Ocelot. In total, these five PMCs were enough to rival the entire United States military.

"Old Snake"
Solid Snake, now suffering from inexplicable advanced aging, had taken to living his life in solitude. During a visit to the grave of Big Boss, a helicopter made a landing within the cemetary, from which Otacon disembarked. Otacon informed Snake that Roy Campbell was waiting for him, and that certain test results regarding Snake's condition had turned out positive and negative for proteome and mRNA analyses, respectively. Snake estimated that he probably had a year left to live in his current condition, at best. Otacon suggested that he see another doctor, but Snake declined, saying that it wouldn't make a difference, as he was never a normal person to begin with, as well as the fact that he was infected with FOXDIE. Campbell, now working in the UN's security council, had found Liquid lurking somewhere in the Middle East.

Returning to their base on board the aircraft Nomad, Campbell explained that private military companies were nothing like the mercenary groups in the past. Meanwhile, Otacon was working on the Metal Gear Mk. II, with Sunny trying to serve him eggs, but Otacon was too busy to eat, hurting Sunny's feelings. Snake and Campbell then discussed about how the Pentagon's new battlefield systems had allowed the use of PMCs, and how ArmsTech (now known as AT Corp) had shifted from weapons development to security development to (as Snake puts it) "make a nice cleaner battlefield." Sunny, upon returning to the kitchen, noticed that there was a recently smoked cigarette butt on the counter and after stamping it out, scolded Snake about smoking. Campbell also explained the situation of the PMCs as well as Outer Heaven, and the revival of Liquid Snake as Liquid Ocelot. Snake, hesitant at first, agreed to a simple mission: to assassinate Liquid, after Campbell explained the situation of what would happen if Liquid wasn't stopped, mentioning that the event would be a severe version of Iron Mountain's Delphi Technique, and that the international community was unwilling to do a thing due to not wanting to harm the "war economy."

"Gekko"
Three days later, Snake made it to the center of the Middle Eastern war zone, in the back of a truck disguised as a member of the local militia. Suddenly, however, the battle lulled, and unmanned Gekko descended on them, slaughtering a number of the militiamen. Snake managed to escape detection and proceeded further into the city.

Further on, Snake met up with the Metal Gear Mk. II inside a ruined building, which handed him a new device: the Solid Eye. Outside, battle ensued, but Snake made it through to the militia's safehouse by assisting them with the battle. Inside the house, he met gun launderer Drebin 893, who offered his services to Snake at a price, which they decided could be provided through the Mk. II. Drebin provided him with an M4 Custom, free of charge. At first, the gun's trigger locked on him, but Drebin injected him with more up-to-date nanomachines, which he stated would allow Snake to fire the weapon.

"Haven Troopers"
Making his way through the war-torn Middle East, Snake eventually made it to the Advent Palace where his informants planned to rendezvous with him. He was surprised to find Meryl Silverburgh waiting for him, with her new CID unit, Rat Patrol Team 01. With Liquid in a camp up ahead, Meryl explained the SOP (Sons of the Patriots) system to Snake. When questioned, Snake claimed that he was there merely to assess the threat of PMC activities on the UN's refugee programs.

After being ambushed by a unit of FROGS, which resulted in a fierce gunfight from the top of the Palace all the way to the basement, Rat Patrol and Snake parted ways.

"BB Corps"
Snake headed north towards the enemy encampment where Liquid had been staying, but after getting involved in another heated battle, he witnessed an entire militia unit get wiped out thanks to the Beauty and the Beast Unit. Shortly afterwards, the whole unit quickly dispersed, leaving Snake to observe the aftermath in awe.

Moving forward into the PMC camp, he made his way closer to Liquid before spotting Meryl and her Rat Patrol nearby. She called him on his Codec, and although angry that he was indeed there to kill Liquid and not threat assessment, she had to begrudgingly let him continue as she felt she was in no position to stop him.

"War Zone"
Before Snake could act, Liquid quietly commanded into his radio, "Activate it." Suddenly, all of the soldiers in the area, the Rat Patrol team included (with the exception of Johnny Sasaki) fell to the ground, foaming at the mouth and violently convulsing with mixed feelings and emotions such as crying, anger, laughing and screaming. Snake was also affected, but not to the degree of the other soldiers. After a moment, Naomi Hunter appeared in front of Snake, injecting herself with a syringe before disappearing, although not before telling Snake that, if he doesn't wish to remain a prisoner to fate, he should go and fulfill his destiny. Snake was then carried to safety by Johnny, the only unaffected soldier in the area.

Behind the scenes
"Liquid Sun" is the name of Act 1 in Metal Gear Solid 4: Guns of the Patriots. Although the act takes place in the Middle East, the end credits suggest that the location's design is actually based on Morocco, which is located in North Africa.

For unknown reasons, Solid Snake reacts to the news about Liquid Ocelot heading the Outer Heaven mother PMC during the Act 1 briefing as if he didn't know that Liquid possessed Ocelot, despite witnessing Ocelot's Liquid persona emerging nearing the end of the Tanker Incident and nearing the end of the Big Shell Incident.