Metal Gear 2: Solid Snake is an overhead action-adventure stealth game, that was initially released by Konami in 1990 for the MSX2. A sequel to the MSX2 version of the original Metal Gear, Solid Snake was designed and written by series's creator Hideo Kojima after he learned of the existence of Snake's Revenge, a sequel for the NES that was being developed specifically for North American and Europe. It was released for the Wii Virtual Console in 2010 exclusively in Japan.
A major oil crisis seriously affects the global economy in the late 1990s, with petrol deposits running out faster than previous estimates. Efforts to adopt alternative energy sources or attempts to drill for more oil fails to take up the slack. To counter the problem, Czech scientist Dr. Kio Marv bio-engineers a new species of algae, OILIX, that could produce petroleum-grade hydrocarbons with little expense and effort. He unveils the algae to the World Energy Conference in Prague and was on his way to a demonstration in the United States when he was kidnapped by soldiers from Zanzibarland, a Central Asian country established in 1997 after a successful independence war against the Soviet Union. NATO discovers that Zanzibarland's leaders plan to hold the world hostage by controlling the supply of oil through OILIX and nuclear warheads pillaged from old stockpiles marked for dismantling in light of global efforts toward nuclear disarmament. FOXHOUND's new commander, Roy Campbell, brings Solid Snake out of retirement and sends him to Zanzibarland to rescue Dr. Marv on Christmas Eve 1999.
Over the course of his mission, Snake teams up with Holly White, a CIA operative posing as a journalist, and Gustava Heffner, an StB agent and Dr. Marv's bodyguard. He is also reunited with Dr. Drago Pettrovich Madnar, the Metal Gear inventor from Outer Heaven, who claims to have been once again kidnapped and forced to work on another Metal Gear project (named Metal Gear D) for Zanzibarland, as well as oversee mass-production of smaller, non-nuclear-equipped Metal Gear units. Snake learns from Dr. Madnar that Big Boss, Snake's former superior, survived the events of the first game and now leads Zanzibarland.
As Snake, Heffner, and Dr. Madnar head toward Zanzibarland's main prison, Heffner is killed by a missile fired by Metal Gear D and Dr. Madnar is recaptured by the enemy. The new Metal Gear's pilot is revealed to be Gray Fox. Determined to finish his mission, Snake fights against Zanzibarland's elite mercenary force and manages to reach Dr. Marv's cell.
Snake arrives too late, as he finds Dr. Marv's corpse and the OILIX data. Holly later tips him off that he actually died under Dr. Madnar's torture. In addition, Snake learns that Madnar volunteered his services to Zanzibarland to finish work on Metal Gear as revenge against the scientific community shunning him after the events of the first game. Snake incapacitates Madnar when the latter attempts to attack him.
Snake faces off against Gray Fox in Metal Gear D and eventually destroys the mech. Both men later fight hand-to-hand in a minefield, and Snake finishes him off. As he tries to escape, Snake meets Big Boss. Having lost his equipment and with no weapons at his disposal, Snake is forced to improvise using the only items he can find: a lighter and aerosol can. Fashioning a makeshift flamethrower, Snake defeats Big Boss for the second time. Snake and Holly escape together, and they deliver the OILIX formula to Campbell.