Unlock Monkey Mask
Get the five best times in Snake Vs. Ape to unlock the monkey mask.
Snake Pukes
Spin snake in circles in the cure menu to make Snake throw up.
Title Screen Fun
On the title screen the [L3] button changes the pattern in the background. R1 speeds up action and R2 slows it down. L1 switches the black silhouette from the foreground to the background and L2 changes the color of the silhouette. L3 changes the color of the pattern in the background.
Radio Frequencies
140.01 - Salty Catfish / 66 Boys
140.52 - Rock Me Baby / 66 Boys
141.24 - Sea Breeze / Sergei Mantis
142.94 - Pillow Talk / Starry.K
144.06 - Jumpin' Johnny / Chunk Raspberry
147.08 - Surfing Guitar / 66 Boys
147.59 - Sailor / Starry.K
149.53 - Don't Be Afraid / Rika Muranaka
Unlock Camouflage
Beat Ocelot non-lethally: Animals - Steady aim
Beat The Pain non-lethally: Hornet Stripe - Wards off insects
Beat The Fear non-lethally: Spider - Trades stealth for stamina
Beat the Fury non-lethally: Fire - Less damage from fire
Get to the end of the Sorrow - Choke people for stamina
Beat Volgin non-lethally: Cold War - Russians will not attack
Unlock Nightmare Mini-Game
After Snake's torture, you can save the game. If you load this save in another game, a sword fighting mini-game will begin.
Unlock Moss Camouflage
When fighting The End, if you sneak up behind him when he is asleep and hold him up, he shakes down and will eventually give you the camouflage moss.
Ocelot Time Paradox
After the cut scene where you first meet Ocelot, knife him to death. Once you kill him the game over screen will pop-up and say "OCELOT IS DEAD." Cambell will then yell at Snake for creating a time paradox.
Raiden Poster
When you steal Raikov's outfit in Groznyg Grad you hide Raikov's body in a locker room on the 2nd floor. Once you take his body in the room, a cut scene will start showing snake putting Raikov's body in a locker. If you look closely, you can quickly see a poster of Raiden from MGS2 on the inside of the door of the locker. This is the locker that contains the sneaking suit later.
Skip The End
In the cut scene when you see The End in a wheelchair, quickly get your gun out (use the sniper rifle if you have it) and shoot his head before he gets back inside the building.
Movie
After you're through with the torture and you're in your cell, leave the transmitter in that's lodged in you rather than extract it with the knife. When you get to the cave with Eva, you'll see a funny cut scene.
Hidden R1 Scenes
Secret 1: When there's the animation with Volgin beating Tatyana, Boss sending The Fear to kill you, The End is there in a wheel chair, etc. When the Boss says: "The Sorrow, is that you?". It gives you a R1 notice, but you're zooming on The Boss. Move the camera to the right to see The Sorrow.
Secret 2: When you kill Volgin on the Shagohad and Eva is about to kiss you, hold R1. You won't get any notice, but it works. You're going to see The Sorrow standing in the background.
Secret 3: After you killing The Boss, once the horse is there, hold R1. You won't get any notice, but it works. You're going to see The Boss spirit with The Sorrow.
Secret 4: When you're shaking hands with the President, hold R1. You won't get any notice, but it works anyway. Move the camera to the left to see Ocelot doing his trademark taunt from the window.
Secret 5: When Big Boss is standing in front of The Boss's grave, hold R1. You won't get any notice, but it works anyway. You're going to see the complete Graveyard.
Secret 6: When Ocelot is leaving the Torture Room, Press R1. You won't get any notice, but it works anyway. You're going to see The Boss doing Ocelot's taunt.
Prison Cut Scene
When the guard throws the food in, throw it back. After doing this 3 times, you'll get a cut scene. He'll also give you an item that should make the escape a little easier.
The Three Snakes
In the last Boss battle between you and The Boss, there are three logs, check all of them, you should recover three snakes, each pure white. The Snakes' names will be, Snake Liquid, Snake Solidus, and Snake Solid.
Prison Cell
When the clip in the torture room ends, The Pain is in the background holding a sign that reads 144.75. Put that code into your radio when you're in the prison cell. It unlocks the door! That's pretty good for a girl who just watches her boyfriend play video games all day long!
Another way to escape the prison cell Snake is being held in is to go into the menu and do the Snake viewer and start spinning him around. When you return to the game Snake should puke on the ground, the guard sees this and comes in, giving Snake the opportunity to knock him out.