In-game reset:
Hold L + R and press Start + Select during game play.
Sunglasses:
After completing the game twice, Snake and Raiden will be wearing sunglasses.
European Extreme difficulty:
Successfully complete the game under the normal difficulty setting.
Boss survival mode:
Successfully complete Sons Of Liberty under any difficulty setting.
Photograph mode:
Successfully complete bomb disposal mode, hold up mode (alternative missions), and eliminate mode to unlock photograph mode in the VR Missions.
Casting theater option:
Successfully complete Sons Of Liberty under any difficulty setting.
Ninja Raiden:
Successfully complete 50% of the VR missions as Raiden to unlock Ninja Raiden in the VR Missions.
Pliskin:
Successfully complete 50% of the VR missions as Snake.
Raiden X:
Successfully complete 100% of the VR missions as Raiden and Ninja Raiden.
Tuxedo Snake:
Successfully complete 100% of the VR missions as Pliskin.
Metal Gear Solid 1 Snake:
Successfully complete 100% of the VR missions as Snake, Pliskin, Tuxedo Snake, Raiden, Ninja Raiden, and Raiden X.