Successfully complete Campaign mode to unlock Arcade mode; level concept art; chapter concept art; vehicle and weapon concept art; "Depth Of Field" option (more colorful view); "Motion Blur" option (blurry view); and "Screen Tint" option (black, white, yellow, and blue only view).
Successfully complete the game on the Difficult difficulty to unlock the Superhuman difficulty.
Get three Silver trophies to unlock the mirror levels.
Get five Silver trophies to unlock the Super Hybrid weapons.
Reach the indicated level in Co-op mode to unlock the corresponding Berserk, gear, or weapon. Note: You must have sufficient Grey Tech to purchase the unlocked item.
Medic items
Soldier items
Special Ops items
Reach the indicated level in Competitive mode to unlock the corresponding item:
This trick requires two controllers. To play Co-op mode by yourself without dying and ending the mission, press Start on the second controller. Choose a class, and start the mission. Leave that player safe somewhere away from danger, then go and complete the mission with the other player. You will respawn instead of dying and ending your mission. You also can gain levels without going online.
This trick requires two players in Co-op mode. One player must play as Special Ops. Have the non-Special Ops player fire one shot from his or her weapon, and go to a control panel that requires a second player at another panel. While the player is at the panel, the Special Ops player can throw an unlimited amount of ammo boxes at the other player. The Special Ops player will keep getting experience for each box.
You can see an Easter Egg under the broken off bridge. Walk out on the single beam in the middle, then turn around, and look to the bottom left to find it.
In Twin Falls, enter the tunnel, and get inside a subway car. Destroy the pods inside, and some will have a Moai head from Easter Island. These heads were also hidden throughout various Metal Gear Solid games.
In Co-op mode, zoom in on a prototype ammo kit on the ground. The phrase "MGS4P4WNS" can be seen on the exterior of the kit.
Instead of playing the entire game on the Superhuman difficulty, simply complete the last chapter on that difficulty to get the "OMGWTFBBQ" trophy.
Successfully complete one of the following tasks to get a trophy:
Additionally, there are nine secret trophies: