**Will be updated over time. If you have stuff you want to add to the list either reply with it in this thread...or PM me and i'll add it to this initial post.**
MGS4 Guide
Unlockable: Bonus Weapons
World War I Pistol - Earn the Hound emblem on a single-player session by doing the following: instigate no more than 3 alerts (the third alert means failure); kill no enemies (not even bosses); do not continue (at all); do not use life recovery items (at all); do not use the stealth suit or bandanna special items (you may possess, but not activate them); and complete the game on Naked Normal difficulty (or higher) under 6 hours and 30 minutes.
Desert Eagle, Long Barrel - Earn the Fox emblem on a single-player session by doing the following: instigate no more than 5 alerts (the fifth alert means failure); kill no enemies (not even bosses); do not continue (at all); do not use life recovery items (at all); do not use the stealth suit or bandanna special items (you may possess, but not activate them); and complete the game on Naked Normal difficulty (or higher) under 6 hours.
Thor 45-70 - Earn the Fox Hound emblem on a single-player session by doing the following: instigate no more than 3 alerts (the third alert means failure); kill no enemies (not even bosses); do not continue (at all); do not use life recovery items (at all); do not use the stealth suit or bandanna special items (you may possess, but not activate them); and complete the game on Big Boss Hard difficulty (or higher) under 5 hours and 30 minutes.
Patriot Future Assault Weapon - Earn the Big Boss emblem on a single-player session by doing the following: instigate no alerts; kill no enemies (not even bosses); do not continue (at all); do not use life recovery items (at all); do not use the stealth suit or bandanna special items (you may possess, but not activate them); and complete the game on Big Boss Extreme difficulty under 5 hours.
Patriot sub-machine gun - Successfully complete the game with a "Big Boss" rank to unlock the Patriot sub-machine gun, which has infinite ammunition.
Race (Ricochet) Gun - Clear the single-player game once.
Solar Gun - Collect the five statues (those of the four Battle Beauties and the Frog Soldier/Haven Troopers in stage 1) using non-lethal means on their respective idols.
* Frog Statue - Stage 1 Middle East, Advent Palace garage, atop the Nomad vehicle.
* Octopus Statue - Stage 2 South America, Research Lab boss room, upper right room.
* Raven Statue - Stage 3 Europe, top floor of the human phase of the boss fight.
* Wolf Statue - Stage 4 Shadow Moses, behind Snake's starting spot in the human phase of the boss fight.
* Mantis Statue - Stage 5 Outer Heaven, near the northern most door during the human phase of the fight.
Scanning Plug S - Log more than 10 hours of Metal Gear Online play time on the same profile as your Metal Gear 4 game. You purchase this from Drebin.
Digital Camera - In the Nomad vehicle during the mission intermission; you can unlock a special photo by picking up this item in stage 4 instead of earlier.
Stealth Item - Complete a single-player session without instigating a single alert (caution is okay, but not alert). You can do this on any difficulty.
Bandanna - Complete a single-player session without killing anyone (including bosses). You can do this on any difficulty.
Unlockable: New Difficulty
Earn the final level of difficulty "Big Boss Extreme" by completing the single-player mode once (and saving the cleared data). Load the cleared data to reap your benefits.
Unlockable: Combat Vests
Clear the single-player game once to unlock new combat vests for Snake.
Unlockable: iPod Tunes
Snake's iPod can download specific tunes throughout the course of the game. Some songs have an additional "secret" effect when it is played in the game.
Beyond the Bounds - Stage 4 Shadow Moses, Tank Hangar. After power is restored, backtrack to the upper catwalk and explore all rooms. When played, this tune increases stun damage done by Snake from non-lethal weapons.
Big Boss - Earn the Big Boss emblem (see another code on this page for the criteria). This tune will increase stun damage (as above) and increases Snake's accuracy when played.
Bio-hazard - Stage 3 Europe, Midtown. Hold-up a resistance soldier and perform a body search. This tune will cause soldiers held by Snake to scream in terror.
Destiny's Call - A random gift from a militia or rebel soldier if Snake gives them a healing item. Naturally, the faction should be allied or neutral, or they will not reciprocate. This tune will cause soldiers held by Snake to go enraged.
Flowing Destiny - Stage 4 Shadow Moses, Canyon. Before leaving the canyon area, examine the rocky walls for a hole hiding this item. This tune will cause soldiers held by Snake to weep like a little girl.
Fury, The - Stage 2 South America, Cove Valley Village. Inside the fire ravaged house. This tune will cause soldiers held by Snake to go enraged.
MGS 4 Love Theme / Action - A random gift from a militia or rebel soldier if Snake gives them a healing item. Naturally, the faction should be allied or neutral, or they will not reciprocate. This tune will cause soldiers held by Snake to weep like a little girl.
Opening - Old L.A. 2040 - Stage 4 Shadow Moses, Nuclear Warhead Storage B2. Input 78925 into Otacon's lab computer. This tune will increase Snake's accuracy.
Policenaughts Ending - Stage 4 Shadow Moses, Nuclear Warhead Storage B2. Input 13462 into Otacon's lab computer. This tune will cause soldiers held by Snake to fall asleep on touch.
Rock Me - Stage 2 South America, Confinement Facility. Island in the south-eastern quadrant. This tune increases Snake's amount of life recovered from items and other means.
Sailor - Stage 2 South America, Vista Mansion. Between the east wall and a cargo container. This tune increases Snake's amount of life recovered from items and other means.
Show Time - A random gift from a militia or rebel soldier if Snake gives them a healing item. Naturally, the faction should be allied or neutral, or they will not reciprocate. This tune will cause soldiers held by Snake to scream in terror.
Snake Eater - Unlocked by earning all 40 game clear emblems. This tune will increase the life recovery rate of Snake through items and other actions.
Subsistence - Play at least one game of Metal Gear Online. You must start the match with at least two players (and not simply wander around alone or on the Training Servers). This tune will increase Snake's accuracy.
Unlockable: Facepaint / Masks
Metal Gear Solid Snake - Start the Shadow Moses level.
Young Snake - Start the Eastern Europe level.
Young Snake with bandana - Start the Eastern Europe level.
FaceCamo - Defeat the Battle Beauty Laughing Octopus (the overall battle, no specifics involved).
Laughing Octopus - Defeat the Battle Beauty (human form) Laughing Octopus by non-lethal means.
Raging Raven - Defeat the Battle Beauty (human form) Raging Raven by non-lethal means.
Crying Wolf - Defeat the Battle Beauty (human form) Crying Wolf by non-lethal means.
Screaming Mantis - Defeat the Battle Beauty (human form) Screaming Mantis by non-lethal means.
Roy Campbell - Shock Colonel Campbell using the Metal Gear II during the intermission scene.
Otacon - Shock Dr. Emmerich using the Metal Gear II during the intermission scene.
Raiden Mask A - Shock Sunny using the Metal Gear II during the intermission scene.
Raiden Mask B - Shock Dr. Naomi Hunter using the Metal Gear II during the intermission scene.
Drebin - Purchase and keep more than 60 different weapons.
Big Boss - Earn the Big Boss emblem on a single-player session by doing the following: instigate no alerts; kill no enemies (not even bosses); do not continue (at all); do not use life recovery items (at all); do not use the stealth suit or bandanna special items (you may possess, but not activate them); and complete the game on Big Boss Extreme difficulty under 5 hours.
Unlockable: Costumes / Skins
Business Suit - Clear single-player mode once.
Altair's Rags - Earn the Assassin's emblem on a single-player session by doing the following: kill or stun 50 or more enemies; CQC hold 50 or more enemies; and be discovered fewer than 25 times.
Civilian clothes: Start the Eastern Europe level.
Infinite ammo bandana: Successfully complete the game without killing any enemies. Alternately, purchase it from Drebin for 5,000,000 DP after starting another game session after completing the game.
Metal Gear Solid optical camo: Successfully complete the game without going into alert phase. Alternately, purchase it from Drebin for 5,000,000 DP after starting another game session after completing the game. This camo makes you completely invisible.
Middle East militia disguise: Go to the Middle East militia safe house.
South American militia disguise: Go to the South American cove valley village.
Suit: Successfully complete the game.
No More Camo
Shake the Sixaxis controller to return Snake's Octocamo to its neutral (black and blue) pigmentation.
Emblems
Successfully complete the indicated task to unlock the corresponding Emblem:
Ant : Must frisk 50 enemies for items.
Assassin's: Kill more than 50 enemies with the knife, have over 50 CQC holds, and get discovered less than 25 times.
Bear : Must use CQC chokes to defeat 100 enemies.
Bee : Must use scanning plug or syringe on 50 enemies.
Big Boss: Successfully complete the game on the hardest difficulty, using no continues, getting no alerts, killing no enemies, using no rations or stealth suit, and with a completion time of five hours or less.
Blue Bird : Must give rebel soldiers 50 items. (To do so, equip item and press TRIANGLE near soldier.)
Eagle : Must land 150 headshots.
Frog : Must roll or dive sideways 200 times.
Gecko : Must attach to walls for a total of 60 minutes.
Giant Panda : Must complete the game after 30 hours of play.
Gibbon : Must hold up 50 enemies.
Hawk : Must be praised by rebel soldiers 25 times.
Hog : Must get 10 combat highs—firing your weapon 100 times during an alert triggers one combat high.
Hyena : Must pick up 400 dropped weapons and/or items.
Inch Worm : Must spend 60 minutes crawling.
Little Gray : Must collect all 69 weapons in the game.
Lobster : Must spend 150 minutes crouching.
Rabbit : Must flip through 100 pages of the nudie magazines by holding L1 + R1 and tapping CIRCLE.
Scarab : Must execute 100 dive rolls.
Tortoise : Must hide inside a cardboard box or drum barrel for a total of 60 minutes.
*New Emblems* Submitted by FireStorm^ -
Centipede: Must continue 26 times.
Chicken: Must trigger 150 alerts, kill 500 enemies, continue 50 times, use 50 health items, and complete the game after 35 hours of play.
Cow: Must trigger 100 alerts.
Jaguar: Must trigger 76 alerts.
Leopard: Must kill 76 enemies and continue 26 times.
Panther: Must trigger 76 alerts and kill 251 enemies.
Puma: Must trigger 76 alerts, kill 251 enemies and continue 26 times.
Spider: Must kill 251 enemies and continue 26 times.[/size][/color]
Weapons list
The following weapons are available in the game:
Pistols
1911 Custom
Desert Eagle
Desert Eagle Long Barrel
Five Seven
Glock 18C
GSR (.45)
Mk 2 Pistol (Tanq)
Mk.23 SOCOM
Operator (Colt .45 with extended barrel)
PMM
PSS
Race Gun (fires ricochet bullets)
Solar Gun (causes enemies to drop weapons and causes extreme damage to Vamp)
Thor .45-70 (rifle pistol)
Type 17 (broom handle machine pistol)
Sub-machine guns
Bizon
M-10
MP5sd2
Mp7
P90
Patriot (has unlimited ammunition)
VZ. 83 Skorpion
Assault rifles
Ak102
An94
FAL Carbine
G3A3
M4 Custom
Mk.17
XM8
Sniper weapons
DSR-1
Heavy machine guns
HK21E
M14EBR
M60E4
M82A2
MK.46 Mod 1
Mosin-Nagant
PKM
RAIL GUN
SVD
Tanegashima (old flint lock that is very slow to reload, 33% of hits causes a whirlwind that carries off enemies making them drop items)
VSS
Shotguns
M870 Custom
Saiga-12
Twin Barrel
Grenade launchers
MGL-140
XM25
Rocket launchers
Fim-92A (Stinger)
Javelin
M72A3
RPG-7
Weapon modifiers
Dot sights
Flashlights
Fore grips
Grenade launchers
Laser sights
Masterkey (under barrel shotgun for assault rifles)
Scopes
Suppressors
Others
C4
Chaff grenade
Claymore
Grenade
Knife
Molotov cocktail
Sleeping gas mine
Sleep gas satchel charge
Smoke grenades (yellow, red, blue, green)
Stun grenade
White phosphorus grenade
Beating Final Boss (Liquid) on Hard Difficulty Submitted by xxGhost_Wolfxx
If you get to the last fight against liquid on big boss hard you can regain health as well if you don't already know how.
First when your fighting liquid and he hits you really hard and he steps back an says "Snaaaaaake" Press Triangle and you get health back
I basically CQC'd him to death. But once he gets to Ocelot you have to straight up fight him.
Once hes at about 33% health they turn old and you just have to tap R1 like crazy.
Linear Mode
