Deep in South Africa lay a small country named Outer Heaven, where an armed fortress was erected by a heroic, but insane, mercenary. Inside the fortress was none other than the first Metal Gear. Special Forces squad FOXHOUND were tasked with infiltrating the fortress and discovering more about this new weapon. Operative Gray Fox was assigned mission "Intrude N313", but communication was lost with him days later. Sent to investigate was operative Solid Snake, who found Gray Fox and also discovered that Metal Gear was a nuclear capable walking tank. Solid discovered how to destroy Metal Gear, but afterwards finds that Big Boss, leader of FOXHOUND, had been using him for evil purposes. A battle between them ensues and Solid defeats Big Boss
Using a huge arsenal of weapons and gadgets such as Remote Control Missles, thermal goggles, or even an antenna to use the radio in areas with electronic jamming, the player must go through the game anyway they want. They can either sneak through it, trying not to be known to the enemy, or they can even run in, guns blazing and shooting everything in sight if they really want. It's up to the player, and the player gets a bunch of weapons and items to use.
- Many different items can be found to help you achieve your mission, some of which you need to advance through certain areas in the game.
- Weapons include handguns, machine guns, plastic explosives, mines, and even a grenade launcher!
- Advance your rank by rescuing many hostages in jail cells and other places.
- Need help? Use the codec to have other operatives tell you where to go or where to find an item.