Gameboy Codes

Men In Black 2
Gameshark Codes
Infinite Lives 010991C8
Infinite Health 015F90C8
All Glasses Collected 010488C2
Stop All Objects From Moving 01C889C4

Metal Gear Solid
Sound menu
Successfully complete the VR training missions with a 100% ranking. The sound menu will be unlocked at the options screen and allows all game sounds and music to be played.

Special stage select
Successfully complete the game on the easy or greater difficulty setting. The special stage select allows any level to be played with new mission objectives.

Plot Revelation
Successfully complete stages in the special stage select to get No. 4 to reveal pieces of the plot.

Automatic ration use
By equipping rations as opposed to simply using them, they will automatically be used by Snake when needed. This is especially useful in Boss battles, or when there is a chance of being hit by a powerful attack.

Mission Impossible
Game Shark Codes
Infinite Lives 010923DB
Bullet Proof Vest 010318DB
Stealth Modifier 01??2ADB 01??2BDB