Snake 6-6 aid the regular United States Marines in holding off a massive PLR attack in Iraqi Kurdistan. They rack up over a hundred confirmed kills and four armor kills (five if including a Technical), allowing the Marines to successfully evacuate from the region.
Snake 6-6 attempt to extract a defecting PLR informant—Hamid Al-Zakir, who is situated in an apartment complex in the outskirts of Baghdad, Iraq. Initially it goes smoothly, with Snake 6-6 able to infiltrate the enemy stronghold where Al-Zakir is being held. However, the plan quickly goes awry as, vehicle by vehicle, the convoy escorting Al-Zakir out of the city is destroyed. They manage, however, to successfully evac after getting pinned down in a courtyard waiting for a UH-1Y Venom to arrive.
Snake 6-6 head to Levin Cooperative in central Paris in order to download some intel from a computer. Unfortunately, the company's private security personnel try to stop them from doing that. Once done, the duo make their way to the underground garage to get to their escape car while taking out some guards. When they reach the car, they drive as fast as they can, while evading RPG rockets and the waves of security closing in. Fortunately, they escape successfully and later find out that an attack in Paris will happen soon.
Snake 6-6 goes to Paris as a hostage situation headed up by Abu Muhammad develops in the Embassy. Equipped with suppressed M9s and Mk 11s, they provide overwatch for a Marine strike team as they advance through PLR-controlled streets. They silently eliminate several patrols of operatives, and then pick off the operatives guarding the hostages in the two metro buses at the first stop. Snake 6-6 then abandons their initial vantage point, moving parallel to the strike team across the Seine Crossing while maintaining overwatch. Finally, they set up at a balcony across from the Embassy, and again provide overwatch as the strike team moves in. Finally, Snake 6-6 eliminates Abu Muhammad as he attempts to flee through a window.
The duo are tasked with assaulting a Parisian metro filled with PLR cell operatives who plan to use a nuclear bomb to destroy the city. After donning gas masks and pushing through over 30 hostiles, they reach a train carriage where the bomb has been armed. One of the team must disarm the device while the other has to defend against the constant stream of PLR gunmen coming down the escalator. With the bomb safely deactivated, the team then goes to the surface and fights through the Paris Stock Exchange. At the end of the level, the two must breach a door. When storming the room, Abdul Rahman takes one of the team hostage, and threatens to detonate a second nuke. The captive must break free, and the other team member must execute Rahman.