Open the Radio screen and tune to the following.
||Opens locked door in East Weapons Lab
||Jumpin' Johnny and Chunk Raspberry
||Alert mode cancelled
||Don't be afraid
Alternate Groznij Grad escape:
Go into the survival viewer and use cure to remove the bullet, which you'll see is actually a fake-death pill. Take that sucker. When the guard comes to check you out, escape when he leaves the door open.
To reload faster, press R2 twice very quickly. This helps with slow loading stuff like the RPG.
Monkey mask and Banana camouflage:
Beat all Snake vs Monkey record times.
When Snake is caught in Groznyj Grad save the game, then load the save file.
Beat Volgin Easily:
Tired of waiting for the perfect time to shoot Volgin? Well, run up to him and CQC grab him (press ). Let him break free, and when he does, quickly pull out your weapon and shoot him before his shield reactivates. The M37 shotgun seems a smart choice. If you're having trouble grabbing Volgin, wait until just after he finishes an attack.
When fighting Volgin, put on the Raiden Mask and the officer suit. Volgin will think its his missing "friend", giving you time to shoot him a few times. Try it, it is funny hearing him talking sweet to you.
Reveal The End's Map Location:
When fighting The End, press Start and choose MAP. Then press Up, Up, Down, Down, Left, Right, , .
The End's position will show up. You will have to do this every time you enter the MAP.
Easiest Way to Stamina-Kill The End:
Sneak up behind him and use the Cig gas-spray.
Skip The End's boss fight:
There's an area where you must swim across some open water to some guarded docks, and you can kill The End here if you use the Dragonov to shoot him and his guard immediately after the cut-scene in which he is wheeled out to the docks.
Another way to skip The End:
When your battle against The End begins, save the game. Then, restart your PS2 and set the system clock ahead one week. When you resume the battle, you'll get a calling informing you The End has passed away.
Fun with the X-Ray:
Go to the cure screen and tap R1 twice.
Bonus Snake vs. Monkey levels:
Beat the game.
Go to the character viewer, spin Snake around for awhile, then press Start.
R1 during the ending:
There are unmarked portions of the ending sequence where you can use the R1 button.
After the cut-scene where you first encounter Ocelot, cut him up and the game will end due to a Time Paradox.
Beat the pain by draining his stamina to get the hornet uniform. Then, with the hornet camo equipped, stand under a bee hive and shoot it down. As the bees are swarming around you walk over near an enemy.
If you grab a guard and interrogate him during an alert he'll give you a frequency to call that will cancel the alert.
Collect every type of plant and animal in the game.
Invulnerable through torture:
Hold L2 throughout the entire cutscene until Volgin leaves.
Beat Volgen Easily:
Make sure you have TNT. Get him as close as possible to the TNT, then blow him up. Pull this off 4 times and he'll be on the ropes. Then finish him.
Hidden cutscene 1:
When Snake is captured in the prison cell, throw the food back out of the cell 3 times to the guard rather than eating it.
Hidden cutscene 2:
After you escape from the cell, do not use Cure to take out the transmitter in your back. Keep it in you and meet up with Eva behind the waterfall.
Special thanks to Revolution readers MANHUNTer, Z3RO, Imperious B, Hazen, Freddy, Cesar, Void, Flooboo, Alex Wellerstein, Andy Miller, D money,King and Rasmus!