To unlock all of the Snake vs. Monkey missions on Disc 2, first play Disc 1. When starting a new game on Disc 1 and are asked which Metal Gear Solid game you like, select option 4, I like MGS!. When the game starts, save it as soon as you can. Take out Disc 1 and insert Disc 2. Go to Snake vs. Monkey and all of the missions should now be unlocked instead of having ????? in their place. Doing this also unlocks the Demo Theater on Disc 1 and the Secret Theater on Disc 2, along with the Duel option on Disc 2.
Alternate title screen
Complete the game to have Snake wear an eye patch during the CQC fights with the Russian guard at the title screen.
American Flag Face Paint
Complete Snake Eater to unlock the American Flag Face Paint.
Animals Camouflage
Defeat Ocelot through stamina depletion to unlock the Animals Camouflage.
AUSCOM Desert Camouflage
Complete Snake Eater to unlock the AUSCOM Desert Camouflage.
Banana camouflage
Set the top time record in all Snake versus Monkey mode stages.
Bandana in original MSX Metal Gear games
Complete MSX Metal Gear or Metal Gear 2: Solid Snake to unlock the bandanna for that game. When equipped, the bandanna gives you infinite ammunition for all weapons.
Boss Time Trial in original MSX Metal Gear games
Complete MSX Metal Gear or Metal Gear 2: Solid Snake and save the game when prompted to unlock the Boss Time Trial option at the main menu for the corresponding MSX game.
Brown Face Paint
Complete Snake Eater to unlock the Brown Face Paint.
Camera
Complete Snake Eater to unlock the Camera.
Camouflage Download
Save the game during Disc 1 to unlock the Camouflage download option at the main menu on Disc 1. Alternately, select the I like MGS3! option when starting a new game, then save.
Cold War Camouflage
Defeat Volgin though stamina depletion to unlock the Cold War Camouflage.
Control Snake Eater music video
During the Snake Eater music video, press L3 to change the text language. Press R1 to have the singer say Snake Eater. Move the Left Analog-stick to control the snakes.
Control title screen
At the title screen, press L3 to change the background pattern. Press R1 or R2 to control its speed. Press L1 or L2 to change the color of Snake and the soldier. Press R3 to change the screen's color. Press Triangle to turn the background black.
Defeating The End
When you first start to fight him, go into one of the other two areas and not the original one you start in. Run around and roll to dodge his bullets. When he shoots at you, press Start and select Map. One of the sniping locations will be highlighted in red to show you where he is at (if you have uncovered the entire area). To remove the tranquilizer darts from where The End shot you, press Start and select Cure. Select the Knife to remove the tranquilizer darts. Do this as soon as possible to avoid losing stamina.
If you are having trouble defeating The End and do not care about getting his rifle or camo, you do not have to fight him. Rather than trying to shoot him after the intermission sequence and fight guards, you can just skip it all together. When the battle begins, save the game. Ignore what Medic says about saving and her bad feeling. She is just hinting at the fact that The End's health recovers as well as Snake's. After saving the game, turn off the PlayStation 2. Advance the system date ahead one week. When you start the game again, you will get a message that The End has died and there is no battle.
Defeating Volgin
Use the following trick to defeat Volgin on Shagohod easily. When the battle begins, run to a safe place where you know Eva will not ride to. Stop, go to your inventory, and equip the RPG or rocket launcher and some sort of "lethal" sniper rifle. Aim at the spinning drill-shaped wheels on the Shagohod. Make sure the rocket hits one of them. You will notice that the Shagohod has stopped. Take out the sniper rifle and aim it at Volgin's head. One shot to the head should take him out.
Deflecting bullets
When you are being shot at and are using the Single Action Army revolver, press R3 to twirl the gun and deflect the bullets.
Demo Theatre
Start a new game on Disc 1: Subsistence, then save the game. The Demo Theatre option will now be available on Disc 1: Subsistence at the main menu.
Desert Tiger Camouflage
Complete Snake Eater to unlock the Desert Tiger Camouflage.
DPM camouflage
Complete the special duel mode on disc 2 (persistence).
Duel mode
Select the I like MG3! option when starting a new game, then save to unlock Duel mode on Disc 2.
English Flag Face Paint
Complete Snake Eater to unlock the English Flag Face Paint.
European Extreme
Select the I like MGS3! option when starting a new game, then save to unlock the European Extreme.
EZ gun
Play the game on the Very Easy difficulty setting to unlock the EZ gun, a silenced tranquilizer weapon with infinite ammunition. Alternately, capture all 48 types of edible plants and animals.
Finding The End
When battling The End, go to the map screen press Up(2), Down(2), Left, Right, Left, Right, Square, Triangle to see him on the map.
Fire Camouflage
Defeat The Fury through stamina depletion to unlock the Fire Camouflage.
Flectar Camouflage
Complete Snake Eater to unlock the Flectar Camouflage.
French Flag Face Paint
Complete Snake Eater to unlock the French Flag Face Paint.
German Flag Face Paint
Complete Snake Eater to unlock the German Flag Face Paint.
Green face paint
Complete the normal duel mode on disc 2 (persistence).
Head Shot online game type
Create an online room and enter HEAD SHOTS as its name. Matches played in this room will be a Head Shot game type. You must shoot your opponents with headshots or your character will explode.
High score in Duel mode
A good way to get a high score is to choose one weapon and kill the Boss as fast as possible. It also helps if you collect ammunition for your weapons before defeating the Boss. The shorter the time and more ammunition you carry, the higher the score. You will not lose points for damage or using your medical items.
Hillarious Glitch!!!
Ok, I found this funny glitch. Do you know that rope bridge that snake falls off of after Sokolov is captured? Well I found out that if you shoot the rope next to him with a gun, and write before he falls off you shoot him with an EZ gun or any tranquilizer gun. He will fall as if he fell on the ground when really he is floating in mid air! Then the gaurd will wake up (after a while), stand up, and fall with a yell! Just like a cartoon. LOL.
NOTE- you may have to be on very easy mode. . .
Hornet Stripe Camouflage
Defeat The Pain by stamina depletion to unlock the Hornet Stripe Camouflage.
Infinity Face Paint
Catch a live Tsuchinoko by using mousetraps to unlock the Infinity Face Paint. Alternately, Complete the game with the Foxhound rank.
Infinity Face Paint
Catch a live Tsuchinoko by using mousetraps to unlock the Infinity Face Paint. Alternately, successfully complete the game with the "Foxhound" rank.
In-game reset
While playing the game, hold L1 + L2 + R1 + R2 + Select + Start to return to the title screen.
Italian Flag Face Paint
Complete Snake Eater to unlock the Italian Flag Face Paint.
Japanese Flag Face Paint
Complete Snake Eater to unlock the Japanese Flag Face Paint.
Killing the guard in the cell
After you get out of the torture room you will be placed in a cell with one guard. When he gives you some food, eat it then select Cure in the pause menu. With R3 and L3, move Snake around for about seven seconds. Leave the pause menu and once you are back in the cell, Snake will vomit. The guard will come in and look at you. Then, use the fork to stab him until he dies.
Monkey Mask
Complete Snake vs. Monkey mode to unlock the Monkey Mask.
Mosin Nagant tranquilizer sniper rifle
Defeat The End with the Mk22 to get the Mosin Nagant tranquilizer sniper rifle.
Moss Camouflage
Hold up The End to unlock the Moss Camouflage.
Motion capture model names
When the name of a character appears in parenthesis during an intermission sequence, press Circle. The name will change to the person that provided the motion capture actions for that character.
Patriot (The Boss' gun)
Complete Snake Eater to unlock the Patriot (The Boss' gun).
Play as Reiko and Dixie
Accumulate 50 hours of online game play time to have Reiko and Dixie from Rumble Roses replace Ocelot and Raikov. Alternately, host an online game after reaching the Doberman (DOB) rank in Online mode.
Punching guards in crotch
Get to the part where you have to find Major Raikov and take his uniform. Dress up like Ivan Raikov and go to the other gaurds. They must salute to Ivan. During that time, go into first person view and aim at a guard's crotch and punch them. The guard will grab his crotch and fall face down, knocked out. This can also be done when you go into the research facility where you must find Granin. Dress up like a scientist and punch the guards or other scientists in the crotch.
Quick reload
To quickly reload, press R2(2).
Scorpion
The Scorpion is a SMG and it can be found on the first floor of the East Wing (with scientists running around). There is a locked room. It has doors on either the main lobby side, or the small hallway along the back heading towards the bathroom. The doors will only open for guards or scientists. Either sneak in behind one, or kill/tranq/knock out one and drag him up to the door. Inside you will find some ammunition and the Scorpion.
Secret camouflage room
Complete both 'New Game' types.
Secret Theatre
Start a new game on Disc 1: Subsistence, then save the game. The Secret Theatre option will now be available on Disc 2: Persistence at the main menu.
Secret Theatre
Save the game during Disc 1 to unlock the Secret Theater option at the main menu on Disc 2. Alternately, select the I like MG3! option when starting a new game, then save.
Single Action Army revolver
Select the Single Action Army on the right during the final duel to unlock the Single Action Army revolver.
Snake Camouflage
Defeat The Boss through stamina depletion to unlock the Snake Camouflage.
Sneaking Suit Camouflage
When you return to Grazni Grad for the second time, go upstairs in the East Wing. Find the locker you stuffed the Major into. It looks slightly different than the others (has red markings). Inside is the Russian Prototype for the sneaking suit. It will reduce damage you by half and reduce stamina loss.
Soviet Flag Face Paint
Complete Snake Eater to unlock the Soviet Flag Face Paint.
Spanish Flag Face Paint
Complete Snake Eater to unlock the Spanish Flag Face Paint.
Spider Camouflage
Defeat The Fear through stamina depletion to unlock the Spider Camouflage.
Spirit Camouflage
Walk all the way to the end during The Sorrow fight to unlock the Spirit Camouflage. In the dream sequence where you face The Sorrow (at the stream with lightning and ghosts), walk all the way forward until you see The Sorrow's ghost hovering over his skeleton. Let him kill you while standing over his skeleton then press R2 when the screen reads Game Over - Time Paradox to access the Revival Pill. If done correctly, you should now have The Sorrow's Camouflage in your uniforms. The camouflage's special abilities eliminate all footstep noises from you. You can also drain enemy stamina in CQC holds and add it to your own.
Stealth Camouflage
Shoot all the green frogs in the game to unlock the Stealth Camouflage. Alternately, Complete the game with no alerts. A good way to get the Stealth Camouflage with no alerts is, if you do get seen, immediately save the game and enable the In-game reset code to return to the title screen. Reload the game and you will begin at your last location with no alerts. Keep using this process until the end of the game in order to get the Stealth Camouflage on any difficulty setting.
Swedish Flag Face Paint
Complete Snake Eater to unlock the Swedish Flag Face Paint.
Tuxedo Camouflage
Complete Snake Eater to unlock the Tuxedo Camouflage.