Metal Gear Solid: The Twin Snakes Cheats

Alternate ending:
Finish the game three times to hear alternate music during the ending sequence.

Bandanna:
Finish the game after not submitting to the torture. At the end, Meryl will be alive find a Bandanna on the snowmobile. She will give you the bandanna. When equipped, the bandanna will allow unlimited ammunition on any weapon when selected.

Camera:
After finishing the game you will unlock the camera. Use the camera to take pictures to see various extras, such as the faces of the development team.

Extreme difficulty setting:
After finishing the game you will unlock extreme difficulty.

Meryl demo mode:
Finish the game after not submitting to the torture.

Otacon demo mode:
Finish the game after submitting to the torture.

Meryl costume:
Finish the game two times after not submitting to the torture.

Otacon costume:
Finish the game two times after submitting to the torture.

Stealth Camo:
Finish the game after submitting to the torture. At the end, Otacon will be with you instead of Meryl. When at the snowmobile, Otacon will give you the Stealth Camo that he was using. 

Tux:
To get the Tux, you will need to get the Stealth Camo and the Bandanna. When you get both those items, you will wear a Tux instead of a stealth suit; also Meryl will wear it and Cyber Ninja will have a red exoskeleton.

Finish the game twice and play a third time. You will play as Snake in his tuxedo. Also Meryl will wear a sneaking suit like Snake's, but a female version of it. Finally, the ninja will be colored red.

Control intermission view:
Wait for the message "Camera Change" or "Camera Free" to appear during an intermission sequence. Hold L + R to zoom or C-stick to change the view.

During the intermission sequences where the screen is black on the top and bottom, press the R to zoom in. The harder the button is pressed, the further the screen will zoom. You can use the C-stick when in this mode to move the camera around to see more of the current scene.

Meryl's view:
When you go to the first level five door and Meryl freaks out before you go into the other door, hold Z to switch to first person mode from her perspective..

Bad stealth change:
Unlike the original Metal Gear Solid, in TS while in stealth mode you cannot just walk through the infrared sensors. If you do, they will go off and alert the soldiers; or in the cargo area (exit from tank hanger to fight M1 tank) the gas will go off when you walk through.