Shadow Moses Island is the setting for the events in the first Metal Gear Solid commonly referred to as the "the Shadow Moses Incident." Located in the Bering Sea as part of the Fox Archipelago, the island is home to a nuclear disposal facility and the site where the government agency DARPA and private military contractor ArmsTech developed and constructed the Metal Gear REX. For these reasons, the site was invaded and held hostage by the rogue Special Forces unit FOXHOUND and its battalion of genome soldiers. The game sees Solid Snake infiltrate the island facility and defeat FOXHOUND while also destroying REX.
A rapidly aging Solid Snake returns to Shadow Moses Island during Act 4 of Metal Gear Solid 4: Guns of the Patriots in his search for Liquid Ocelot. Ocelot's goal on the island is to obtain REX's railgun, which is capable of launching a nuclear missile. Snake retraces his steps through the nuclear disposal facility, which has sat exposed to the elements in the years since the original game. Deep within the base, Snake encounters and does battle with the seemingly immortal commando Vamp, and also encounters his allies Raiden and Naomi Hunter. The mission culminates in a playable battle between Metal Gear REX, piloted by Snake, and Metal Gear RAY, controlled by Ocelot.
By the time of Metal Gear Solid 4, much of the permafrost and glaciers that hindered Solid Snake's progress in the original Metal Gear Solid have melted as a result of global warming. The island and the surrounding Fox archipelago will soon be swallowed by the ocean.
Shadow Moses was also included as an arena in Super Smash Bros. Brawl. Spotlights sweep across the level, and when caught in them the player has a red exclamation mark appear over his or her head. If playing as Solid Snake, the player can contact allies via codec and get information on his current opponents throughout the match.
The rear wall of the level is sometimes broken down by Metal Gear REX, Metal Gear RAY, or two Gekko units.