Metal Gear Solid 4: Guns Of The Patriots PlayStation 3 Cheats

Codes for weapons/ipod songs
Successfully complete the game to unlock the "Password" option at the "Extras" menu. Then, enter one of the following case-sensitive passwords to unlock the corresponding bonus when a saved game is resumed or another game is started. Note: The bonuses will become available when the Mk II can first be used.
Code: - Result:
deskyhstyl - Desert Eagle Long Barrel
mekakorkkk - Mk. 23 (SOCOM from Metal Gear Solid)
mnsoymsyhnto - Mosin Nagant
THOMAS - "Desperate Chase" iPod song
GEORGE - "Gekko" iPod song
THEODORE - "Midnight Shadow" iPod song
ABRAHAM - "Mobs Alive" iPod song



Codes in shadow moses
In Act 4: Shadow Moses, Nuclear Warhead Storage B2, when at Otacon's office, he will ask you for the code. Enter one of the following codes instead of the one that Otacon mentions to get the corresponding bonus:

--NOTE--
you will still get the access denies screen, and you can only enter one per game, when/if you replay the game, you can enter a different one, bear in mind that ipod songs also carry through to the next time you play.
Code: - Result:
14893 - 100,000 DP
78925 - "Opening - Old L.A. 2040" iPod song (This song increases Snake's accuracy.)
13462 - "Policenauts Ending" iPod song (This song causes soldiers held by Snake to fall asleep when touched.)



Altairs costume
Enter the code "aottrykmyn" in the cheat code input.
This will give you the Altair (assassins creed) costume!

Type 17 pistol
Enter the password "jmsotsynrn" at the cheat code input screen
It's a pistol that fires rapid shots like a machinegun. You can fire in Full Auto or Semi Auto mode, and you can't reload it manually: you must fire the whole clip to reload.

100K Drebin Bonus
When entering the password into Otacon's terminal, input 14983. Although incorrect, Snake will (invisibly) gain 100K of Drebin points. Run through the game a few more times with this and the no kills and no alerts bonuses, and you should amass quite a sum of Drebin points.

Otacon's extra passwords
Put these in instead of the code Otacon tells you to at Shadow Moses. You will get the Access Denied scene but afterwards you will get the bonus.
Password: - Result:
12893 - 20% off on store
78925 or 13462 - iPod song

Extras Screen Passwords
These passwords are entered at the Extras screen under Password after beating the game once on any difficulty.
Password: - Result:
thomas - Unlocks "Desperate Chase" iPod Song
george - Unlocks "Gekko" iPod Song
theodore - Unlocks "Midnight Shadow" iPod Song
abraham - Unlocks "Mobs Alive" iPod Song

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.
1. Beyond the Bounds (increases stun damage done by Snake from non-lethal weapons): Stage 4 Shadow Moses, Tank Hangar. After power is restored, backtrack to the upper catwalk and explore all rooms
2. Big Boss (increase stun damage and increases Snake's accuracy when played): Earn the Big Boss emblem
3. Bio-hazard (cause soldiers held by Snake to scream in terror): Stage 3 Europe, Midtown
4. Destiny's Call (cause soldiers held by Snake to go enraged): A random gift from a militia or rebel soldier if Snake gives them a healing item
5. Flowing Destiny (cause soldiers held by Snake to weep like a little girl): Stage 4 Shadow Moses, Canyon. Before leaving the canyon area, examine the rocky walls for a hole hiding this item
6. Fury, The (cause soldiers held by Snake to go enraged): Stage 2 South America, Cove Valley Village. Inside the fire ravaged house
7. MGS 4 Love Theme / Action (cause soldiers held by Snake to weep like a little girl): A random gift from a militia or rebel soldier if Snake gives them a healing item
8. Opening - Old L.A. 2040 (increase Snake's accuracy): Stage 4 Shadow Moses, Nuclear Warhead Storage B2. Input 78925 into Otacon's lab computer
9. Policenaughts Ending (cause soldiers held by Snake to fall asleep on touch): Stage 4 Shadow Moses, Nuclear Warhead Storage B2. Input 13462 into Otacon's lab computer
10. Rock Me (increases Snake's amount of life recovered from items and other means): Stage 2 South America, Confinement Facility. Island in the south-eastern quadrant
11. Sailor (increases Snake's amount of life recovered from items and other means): Stage 2 South America, Vista Mansion. Between the east wall and a cargo container
12. Show Time (cause soldiers held by Snake to scream in terror): A random gift from a militia or rebel soldier if Snake gives them a healing item
13. Snake Eater (increase the life recovery rate of Snake through items and other actions): Unlocked by earning all 40 game clear emblems
14. Subsistence (increase Snake's accuracy): Play at least one game of Metal Gear Online. You must start the match with at least two players

Face paint
Different face paint unlocked for in game use.
1. Big Boss's: Earn the Big Boss emblem on a single-player session
2. Crying Wolf: Defeat the Battle Beauty (human form) Crying Wolf by non-lethal means.
3. Drebin: Purchase and keep more than 60 different weapons.
4. FaceCamo: Defeat the Battle Beauty Laughing Octopus (the overall battle, no specifics involved).
5. Laughing Octopus: Defeat the Battle Beauty (human form) Laughing Octopus by non-lethal means.
6. Otacon: Shock Dr. Emmerich using the Metal Gear II during the intermission scene.
7. Raging Raven: Defeat the Battle Beauty (human form) Raging Raven by non-lethal means.
8. Raiden Mask A: Shock Sunny using the Metal Gear II during the intermission scene.
9. Raiden Mask B: Shock Dr. Naomi Hunter using the Metal Gear II during the intermission scene.
10. Roy Campbell: Shock Colonel Campbell using the Metal Gear II during the intermission scene.
11. Screaming Mantis: Defeat the Battle Beauty (human form) Screaming Mantis by non-lethal means.

Costumes
Complete the indicate task to unlock the corresponding costume.
1. Altair: Obtain the Assassin emblem
2. Civilian Disguise: Start Eastern Europe level
3. Middle East Militia Disguise: Middle East in the Militia Safe House
4. South American Rebel Disguise: South America (Cove Valley Village)
5. Suit: Clear the game once

Big Boss Extreme difficulty
Complete the single-player mode once (and saving the cleared data).

New combat vests
Clear the single-player game once.

Weapons
Complete the indicated task to unlock the corresponding weapon.
1. Bandanna: Complete a single-player session without killing anyone (including bosses). You can do this on any difficulty
2. Desert Eagle, Long Barrel: Earn the Fox emblem on a single-player session
3. 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
4. Patriot Future Assault Weapon: Earn the Big Boss emblem on a single-player session
5. Race (Ricochet) Gun: Clear the single-player game once
6. 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
7. 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
8. 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
9. Thor 45-70: Earn the Fox Hound emblem on a single-player session
10. World War I Pistol: Earn the Hound emblem on a single-player session





Emblems
Successfully complete a single player game with the listed requirements to unlock the corresponding emblem.

--NOTE--
you can get more than one in one playthrough, play through a few times to get more emblems, and because its such an awesome game (well done konami/hideo kojima)

1. Ant: Shake 50 enemies for items.

2. Assassin: Kill more than 50 enemies with knife, have over 50 CQC holds, and get discovered less than 25 times.

3. Bear: Choke 100 enemies to death.

4. Bee: Use the Scanning Plug S or Syringe on 50 enemies.

5. Big Boss: Select the Boss Extreme difficulty, use no continues, get no alerts, kill no enemies (including Bosses), do not use the stealth suit or bandanna special items (can possess, but not activate), and have a completion time less than 5 hours.

6. Blue Bird: Give friendly soldiers 50 items.

7. Centipede: Get less than 75 alert phases, less than 250 kills, and over 25 continues.

8. Chicken: Get over 150 alert phases, over 500 kills, over 50 continues, use over 50 recovery items and complete the game in over 35 hours.

9. Cow: Activate over 100 alerts.

10. Crocodile: Have over 400 kills.

11. Eagle: Get 150 headshots.

12. Fox: Select the Naked Normal or higher difficulty setting, instigate no more than five alerts, kill no enemies (including Bosses), do not continue, do not use any life recovery items, do not use the stealth suit or bandanna special items (can possess, but not activate), and have a completion time less than 6 hours.

13. Fox Hound: Select the Big Boss Hard or higher difficulty setting, instigate no more than three alerts, kill no enemies (including Bosses), do not continue, do not use any life recovery items, do not use the stealth suit or bandanna special items (can possess, but not activate), and have a completion time less than 5 hours and 30 minutes.

14. Frog: Dive or roll 200 times.

15. Gecko: Press against walls for a total of 1 hour.

16. Giant Panda: Complete the game after 30 cumulative hours.

17. Gibbon: Hold up 50 enemies.

18. Hawk: Get admired by 25 friendly soldiers.

19. Hog: Get 10 combat highs.

20. Hound: Select the Naked Normal or higher difficulty setting, instigate no more than three alerts, kill no enemies (including Bosses), do not continue, do not use any life recovery items, do not use the stealth suit or bandanna special items (can possess, but not activate), and have a completion time less than 6 hours and 30 minutes.

21. Hyena: Pick up 400 dropped weapons.

22. Inch Worm: Crawl on the ground for a total of 1 hour.

23. Jaguar: Get over 76 alert phases, less than 250 kills, and less than 26 continues.

24. Leopard: Get over 76 alert phases, less than 250 kills, and at least 26 continues.

25. Little Gray: Collect all 69 weapons.

26. Lobster: Spend a total of 2.5 hours crouching.

27. Mantis: Use no continues, get no alerts, and have a completion time less than 5 hours.

28. Octopus: Get no alert phases.

29. Panther: Get over 76 alert phases, over 251 kills, and less than 26 continues.

30. Pig: Consume over 40 food items.

31. Pigeon: Have no kills.

32. Puma: Get over 76 alert phases, over 251 kills, and at least 26 continues.

33. Rabbit: Look at 100 Playboy pages.

34. Raven: Complete the game in less than five hours.

35. Scarab: Execute 100 dive rolls.

36. Scorpion: Have less than 75 alert phases, less than 251 kills, and less than 26 continues.

37. Spider: Have less than 75 alert phases, at least 251 kills, and at least 26 continues.

38. Tarantula: Have less than 75 alert phases, at least 251 kills, and less than 26 continues.

39. Tortoise: Hide inside a cardboard box or drum barrel for at least one hour.

40. Wolf: Have no continues and use no recover items.





Bonus ammo
Successfully complete the game to unlock the following ammo for purchase from Drebin:
Emotive Cry - causes soldiers 'Cry' emotion to activate
Emotive Laughter - causes soldiers 'Laughter' emotion to activate
Emotive Rage - causes soldiers 'Rage' emotion to activate
Emotive Scream - causes soldiers 'Scream' emotion to activate
Smoke Grenade Blue
Smoke Grenade Green
Smoke Grenade Red
Smoke Grenade Yellow

Multi-player mode: Remove frosty breath
When playing in stages where your breath frosts, have Snake play dead while prone. His frosty breath will no longer be seen by others.

Shoot from inside a dumpster
There are dumpsters throughout the game which you can use to hide. Move in front of them and press Triangle when the prompt appears. Once inside, if you have a handgun, for example The Operator, you can hold L1 to lift up the lid of the dumpster and aim your gun from inside.

Control intermission sequences
During an intermission sequence, press D-pad Up to zoom the camera in then use the Right Analog-stick to pan the camera around. The harder you press Up, the more zoomed in the camera view. Also, some intermission sequences have prompts to see it through Snake's eyes by holding L1 (look for the icon at the top left of the screen); or view flashback images by repeatedly tapping X when a prompt appears (look for the icon at the top right of the screen). You can also pause an intermission sequence by pressing Start.

No More Camo
Shake the Sixaxis controller to return Snake's Octocamo to its neutral (black and blue) pigmentation.

Inheritence
You carry over your Drebin points, weapons, ammunition, items, and special items from a previous game upon game clear. However, Snake will need to encounter Metal Gear II in the first stage to get his stuff back.
Be sure to save your cleared data upon game completion to track your items. Load the cleared data to reap your benefits.

Stealth Tips online
When playing as Snake in the online stealth mode, you should avoid lit areas so you won't cast shadows. Also, in stages where characters emit frosty breath, have Snake play dead while prone to make Snake's breath disappear.

Cheaper drebin prices
Set the PS3 system date to a Wednesday or Sunday, and Drebin will have cheaper prices. Additionally, all of Drebin's prices are cut by 50% during Act 5.

Easy bandanna or stealth
To unlock the Bandana and Stealth Suit easier, wait until Act 5 (Drebin's prices are 50% off) to get the items for 2.5 million Drebin Points each instead of the 5 million Drebin Points they normally each cost.

--NOTE--
this is only if you are playing the game again using the same save, it will not work during the first playthrough as they are not available, plus you will have more drebin points.

Reducing stress/gaining psyche
1. Sit in a box to reduce stress faster, this also regains Psyche.
2. Standing/crouching/lying in shade will also reduce stress quicker.
3. When in a cutscene you lose some due to information/insults/ect. tap X repeatedly to regain some.

Ignored by PMC troops
PMC soldiers will ignore you when wearing Otacon's or one of the Beauty's face paints if you are not attacking or displaying a weapon. This allows you to track the Resistance easier.

Bypassing gecko's easily
Shoot five tranquilizer rounds into the legs of a Gekko. It will collapse and thrash around on the floor. You can walk past without being spotted while that is happening.
Its similar with chaff grenades, although they dont last as long.





Complete weapons list
The following weapons are available in the game:

---Pistols
1911 Custom
Desert Eagle (originally used by Meryl)
Desert Eagle Long Barrel
Five Seven (gun used by Snake when he infiltrated Galuade)
Glock 18C
GSR (.45)
Mk 2 Pistol (Tanq)
Mk.23 SOCOM (Snake's main handgun from Metal Gear Solid)
Operator (Colt .45 with extended barrel)
PMM
PSS
Race Gun (fires ricochet bullets)
Solar Gun (causes enemies to drop weapons and does 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 (The Boss' weapon; 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 (The End's sniper rifle)
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





Another Infinite Drebin Points
When in Shadow Moses, there will be 'Dwarf Gekko'' (the small black rolling robots) Get to an area where they cannot reach you (E.g. a vent, or a room they cannot enter) Shoot at them continuosly, you will get a number of DP per kill. They only take one or two shots to kill. They are on Infinite Respawn, so you have no worry of killing them all. Once you feel you have enough, or get bored, throw a chaff grenade (if available) to confuse them, then get to the next area.
If you are out of Chaffs, roll through them.
A machine gun is best used for this, and dont be afraid to throw in a few grenades.

Regain Health and Psyche
To regain health and Psyche, hold X whilst in the prone position with no weapon equipped. Snake's health and Psyche gauges will begin to recover. This is useful when trying for a no rations/recovery items emblem.

Infinate drebin points (DP)
First, acquire the drum can (you dont need to use it, its the location that you need). You do this by finding the soldier (johnny/akiba) that is hiding in the drum, and using it as a bathroom. After that, go up ahead a few feet, where you will see three crates. When you have gone past them, you will see just two crates, **(STAY BEHIND THEM, DO NOT GO PAST THEM)**. You will also see about three rebel soldiers fighting. One is carrying an RPG and the other two have machine guns. They will die and respawn continuously. You will have a chance to pick up the RPG after the soldier has died three times. Do so because each RPG is worth 6,000 Drebin Points. The important thing is to stay anywhere behind the two crates, otherwise the trick will not work. Going further than the two crates will stop the respawning loop of the soldiers dying. The only way to get the RPG without breaking the respawning loop is to use the Mk II. Also the machine guns are worth a few thousand DP, including the PMC/goverment troops guns, not just the rebels.





Solar gun and statue locations (to get solargun)
The statues required to unlock the Solar Gun can be found at the following locations:

1. Frog: In Act 1: Middle East, Advent Palace garage, atop a vehicle.

2. Octopus: In Act 2: South America, in the Research Lab Boss room, upper right room during the human phase of the fight.

3. Raven: In Act 3: Europe, on the top floor of the human phase of the Boss fight.

4. Wolf: In Act 4: Shadow Moses, behind Snake's starting spot in the human phase of the Boss fight.

5. Mantis: In Act 5: Outer Heaven, near the northern-most door during the human phase of the fight.

--NOTE--
these will only be available if you defeated the boss NON-LETHALLY (mk II, mosin nagant, stun grenades, CQC, ect). If you killed the boss they will not be available.

--NOTE 2--
the solar gun causes enemies to drop weapons and does extreme damage to Vamp. To reload you must stand in sunshine and snake will point the gun up to the sky and shout SUNLIGHT!





Audio flashbacks
Experience the following audio flashbacks to get 1,000 Drebin Points for some of them:

Find the crop circle near the river while tracking Naomi in Act 2 after the Laughing Octopus fight (flashback of the Colonel acting strangely in Metal Gear Solid 2).

Find the Hind (flashback of the end of the Hind confrontation).

The middle of the helipad (flashback of Hind D speech).

The small shack to the West of the area (flashback of "A surveillance camera?!").

Enter through either of the vents instead of the door (flashback Master Miller's introduction).

Stand near the tank hangar's door (flashback of Meryl's "Where I can see you" speech).

Stand in the decontamination room before the hallway to Otacon's office (flashback of Cyborg Ninja fighting Genome Soldiers).

Inside Otacon's lab (flashback of Grey Fox's introduction).

Stand in the filled-in trench leading up to the Comm Towers (flashback of Meryl telling Snake to continue without her).

Climb as far as you can up the Comm Tower nearest where you enter and walk around (flashback of beginning of the Hind confrontation).

In front of the other Comm Tower, facing the exit (flashback of Otacon's "What are you fighting for?" speech).

Stand near the door leading back to the room where you fought Vulcan Raven (flashback of Raven's final speech).

In Shadow Moses, near the elevator (flashback of Infiltration speech).

Return to the crashed Hind chopper after the Crying Wolf fight (flashback of Liquid Snake being shot down).

Aim the Mk.23 SOCOM while at Shadow Moses (Snake will say "Just like old times").

Move the camera view directly overhead and move around (Snake will say "Just like old times").





Some secret 'L1' bits in cutscenes
Naomi's chest: In Act 2, after Snake loses his Psyche when Namoi tells him how long he has, press L1 to look at her chest and recharge Snake's Psyche.

Naomi upskirt: In Act 2, when Snake's talking to Naomi and drops his cigarette, use the hidden L1 option to look up her skirt.

Psycho Mantis' ghost: During the first intermission sequence with Beauty and the Beast, after using the option to look through L1, look to the left to see the ghost of Psycho Mantis.

Sorrow: During the Psycho Mantis intermission sequence, keep L1 held. When Psycho Mantis disappears, you will hear Sorrow say something. Hold L1 (even though you are not prompted), and you will see Sorrow. Press X to start a flashback.





Alternate ending
If you fight Mantis with a Sixaxis controller, the ending is different than if you were using a DualShock 3 controller.

Weird man following snake
When tailing the resistance member, if you look behind Snake, you will occasionally notice a man with a hat and trenchcoat also tailing him. This is how the Scarabs found the hideout. If you try to shoot him, he will duck away around the corner and disappear.

Location To South American Rebel Disguise
To find the South American Rebel Disguise, yeah its in South America (Cove Valley Village), but where in Cove Valley Village is it? Because the area's pretty big!!
Well, when you firstly begin your mission in South America, just simply put guards to sleep. Eventually the hostages will fight back and a few will walk out of the house to your right, if you hear a door open just sneak into the place (With your Solid Eye set to NV) and there it is.

Make wolves follow you
Tranq Crying Wolf (beauty form), and the wolves in the area will follow you. Even more weird, they will have love hearts floating from they're head.

Make wolves attack you
In Act 4, kill one of the wolves after you defeat Crying Wolf. The others will attack you. Call Otacon, and he will wince. Call Rose, and she will tell you that animal cruelty is the first sign of criminal behavior, and says that she will have you psychologically assessed if you continue to kill them. One shot will kill them, so if you do kill any, there arnt many to kill.

Octocamo veteran
When leaning against walls and lying on the ground you will come to realise that your octocamo suit can blend in with a close surface or background. Use this as an advantage to get past unaware guards by blending in with every new background you come across.

Cardboard box
When you have passed the checkpoint on the level where you have to rendevous with the Mk.II (demo level), there will be a set of stairs next to you if you have gone through the buildings on the right hand-side of the street. You will notice that there is a path under the stairs. Pick up the box from underneath the stairs. By equipping this you can hide under the box close to guards. It is extremely satisfying to watch the PMC's/Militia search the box.

Glowing eyes
Use the Solid Eye with the Raiden A mask to make both of Snake's eyes glow red.

EDancing sunny
Play the "Oishii ChuhanSeikatsu" Japanese pop song on Snake's iPod. During that song, press Start to see Sunny dancing at the bottom left corner.

Frog soldiers (haven troopers) reaction to body searches
Hold up a FROG soldier, and body search her. When you would normally ball crush a male prisoner, they will say "You men are all the same", "You're disgusting!", or "Ugh" and kick you.
When you search a FROG soldier when she has no items, she will giggle as if ticklish.
When you search a FROG soldier and touch her chest, sometime she will moan or say "You're pretty good at this".

Lost references
When the game first begins, the channels on the television are numbered 15, 16, 23, and 42, which are part of the number sequence from the television show Lost.

Lunar knights reference
The monitor for the PC used by Sunny has a Lunar Knights screensaver.

Policenauts reference
One of the backgrounds on Otacon's computer is a scene from Policenauts.

Star wars references
In Shadow Moses when Snake is about to get on the lift to fight Vamp, watch as the camera circles around the lift area to see a Darth Vader helmet on the floor.
In the Act 5 briefing, while Mei Ling is explaining the situation to everyone she says something about it being an impenetrable fortress or something similar. Snake then says, "He has his very own Death Star."





MGS1 references
During the Act 1 FROG attack sequence, attack Meryl. She will say the same things she said when you attacked her in Metal Gear Solid.

The password Johnny puts in to disable the laser trip trap is "MERYL SILVERBURGH".

You fight Crying Wolf in the same area you fought Sniper Wolf.

You can find the Hind D still in the Snowfield where you fight Crying Wolf.

During the Mantis fight, switch your controller ports when your television switches to "Hideo 2". Otacon will come on the Codec and notify you that the trick does not work twice. You will also get a suggestion about destroying the bust.

When you die in Act 4, the "Game Over" music from the first Metal Gear Solid will play.

After you die during the final Boss battle and select "Exit", it quickly changes to "Exist". Liquid Ocelot says "Not yet Snake, it's not over yet" and it moves the pointer back to "Continue". This is a reference to a quote by Liquid in the original Metal Gear Solid.





MGS2 reference
Call Rosemary with a ration equipped to see a reference to a sequence that happened in Metal Gear Solid 2, when Raiden calls Snake on the Codec with a ration equipped and comments about Rose's cooking.

MGS3 references
Metal Gear Solid 3 reference
When Drebin and Little Grey jump off of the Stryker, they will land in Naked Snake's pose from Metal Gear Solid 3, when he first arrives for the Operation Virtuous mission.
Equip the Patriot gun to hear music from Metal Gear Solid 3: Snake Eater.
Press L1 to view the description for the Mosin-Nagant. It mentions The End and his sniper duel with Big Boss.

Metal Gear Solid: The Twin Snakes references
If you stare at Meryl's breasts, she will blush similarly to how she did in Metal Gear Solid: The Twin Snakes.

Metal Gear Solid VR Missions reference
During a Codec transmission with Campbell, he will talk about the training PMC soldier's went through. Snake says similar to "...better than those VR missions".





Hideo Kojima
After defeating Screaming Mantis and immediately after Psycho Mantis vibrates your controller, keep pressing X to see Hideo Kojima.

If you prolong the Psycho Mantis fight long enough, the game will show the opening screen, except the word "Kojima" will replace "Konami". The game will then resume the Psycho Mantis fight.

Press L1 to examine the .50 Cal Anti-Material Sniper Rifle to see "Recommended by Hideo Kojima."

When Snake hides from the two Irvings next to the box of watermelons, the box reads "No Place For Hideo."

You can see a ghost image of Hideo Kojima in Otacon's lab using the camera. It is between Policenauts and the poster that from a distance reads "Final Fantasy VI".





Metal Gear Solid series references
Look at the two puppets dangling from Screaming Mantis. The two puppets appear to be Psycho Mantis and The Sorrow from previous Metal Gear Solid games.

When Snake and Naomi talk about war changing and how it used to be "just a game", all of the Metal Gear Solid titles appear in an indexed list. After MGS4, there are a few boxes titled "In Production."

When you first enter Big Mama's hideout and the guards start talking about Snake, press L1 to see posters from Metal Gear Solid, Metal Gear Solid 2, Metal Gear Solid 3, and Metal Gear Solid: Portable Ops.

In the Nomad briefing missions, take control of the Mk II, and go to the right of the helicopter. There are three separately caged chickens, each with its own label: "Solid", "Liquid", and "Solidus". This is a reference to the three Big Boss clones. A further reference to those chickens happens at the very beginning of Act 1 when Sunny is cooking eggs. She says "Only two eggs? Solidus must've taken the day off."

The rubber duck in the upper gantry of the Nomad can also be found in Capture The Flag mode in Metal Gear Online; in the GA-KO camouflage in Metal Gear Solid 3; and floating in the flooded Shell Core in Metal Gear Solid 2.

When you are in the final showdown with Liquid, when it enters the third stage of the fight, Liquid will do Ocelot's signature hand gesture.

Otacon has a model of Rex beside his computer.





Another MGS2 reference
The arms that laughing octopus have are the exact same as solidus from metal gear solid 2, they even have the small serial number on the side, on one of the arms.

Shake Rose's Breasts (funny)
When you speak with Rose on the Codec, shake the Sixaxis to make her breasts move.