Cheats for Metal Gear Solid (GBC)

In-game entertainment
Successfully complete the game, and then start a new game. Dial up 140.07 on the Codec to hear some in-game entertainment.

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.

Birds
When you see birds on the ground, you can be sure that there are guards or guard dogs nearby. If you make the birds fly away, the alarm goes off. If the birds stay, the guards or guard dogs will not know you are there.

Find Chris
Chris says she is wearing a red hat. Remember that her hair is tied behind her. Since some guards also wear red hats, you have to look for the one with long hair. She is the only one with long hair and a red hat. Any others with red hats are obviously guards.

R5
Use the R5 Only when spotted, or in Boss battles. Since it does not have a Suppressor, using it while sneaking around is not a good idea. If you are spotted, use it as much as you want. Just keep an eye on the amount of ammunition you have.

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

Cardboard box (yellow)
Climb the very last ladder in the drainage sewer. The cardboard box (yellow) is in there.

Defeating Metal Gear
At the end of the game you have to defeat Metal Gear. The first time you face him when he is walking, you will see small circles on the ground. These are the shadows of his feet. Watch them until they stop. When one of them stops, put a mine on it then run as fast as possible until he steps on it. Keep repeating this until he is dead.

Reset enemy positions
In most places of the game, you can reset the enemy positions by leaving the screen you are in and returning. This will "reset" the enemy positions to where they were when you first entered the area.

Silent floor
You will learn of the "water" floor sections while in VR training. Like the PlayStation version, if you walk on these sections of flooring, you will make noise. However, if you press Start and crawl over these floor sections, it will be 100% silent. Just make sure that a guard or camera does not see you.

5-7 Suppressor
To get the Suppressor (silencer) for the 5-7, follow the guard instead of entering the fortress. He will enter a small guard post follow him in. Once the short interaction between the two guards ends, get the box next to the guard. It contains the Suppressor. Since the guard is asleep, do not worry about him. Just get the Suppressor and leave.

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

Stun grenades
While they will stun a guard, you will also be calling the other guards' attention. They make a lot of noise, so do not use them unless absolutely necessary.

Cameras
The camera are more difficult than guards. You can press up against the wall to avoid detection in the PlayStation version of the game. However, in this version you will get seen if you do this. To get past a camera, watch its movements. The camera is easily located by radar. A moving orange dot is a camera mounted on the wall. Use a cardboard box and remain still until your a camera has passed you. Use crates for cover and remain undetected. Move to each crate when the camera has passed the next crate.

5-7 ammunition
When you first get the 5-7 and the Suppressor, do not become trigger happy. While the 5-7 is silenced with the Suppressor. It is only useful while you have bullets. Use your fists instead of the 5-7 when sneaking around. Once spotted, use the 5-7 as much as you want.

Candid camera
If you move anywhere in front of a camera, you will be seen. This includes crawling past and even "sliding" past with your back to the wall.