Enter the store, and press Square to detect a saved game file from Uncharted: Drake's Fortune. You will get $20,000 for having a saved game file, and an additional $80,000 for having a completed saved game file. The money can be used in the single player and multiplayer stores.
Successfully complete the indicated task to unlock the corresponding skin for purchase:
Reach the indicated level to unlock the corresponding booster for purchase in Multiplayer mode:
Reach the indicated level to unlock the corresponding taunt for purchase in Multiplayer mode:
Successfully complete the game on the Hard difficulty to unlock the Crushing difficulty.
Successfully complete a task that rewards you with a lot of money. Save the game if it is not at an auto-save area. Exit out to the main menu. Then, load the game to get the reward again. Repeat this as many times as desired.
In Chapter 6, find the pool on a hotel roof. Jump in the pool and swim around to have Chloe and Nate play a game of Marco Polo and get $10,000.
Start a game on a difficulty you have not completed, and play until you get a real gun. Go to the in-game options, set the difficulty to the one you have the Tweaks unlocked on, and enable your Tweaks. Then, save the game, and quit. At to main menu, select "Options", and change the difficulty back to the one you originally chose. Continue the game to play on that difficulty with all your Tweaks enabled.
In Chapter 24 when Flynn forces you to find a way to turn the bridge, press Square to turn and swing at him. He will dodge your attack, knock you down, and give you a message. If you do it again, he will shoot and kill you.
When you are prompted to view your journal by pressing Select, keep flipping back to find an entry with four pictures of Sully, which Nate has apparently drawn over and labeled according to his expression.
When Nate is injured, he can still run at normal speed while carrying a propane tank.
To easily kill the Guardians you fight later in the game, once you kill one, take the gold crossbow it drops, and use it on the others to kill them much quicker than your normal guns.
To defeat Lazarevic, you must lure him near the volatile blue sap throughout the level. When he is within range, shoot the sap to cause it to explode.
When you are prompted to view your journal by pressing Select, look for the picture labeled "Angry Eddy". Eddy was one of Drake's enemies from Uncharted: Drakes Fortune. Additionally, one of the unlockable guns in Single Player mode is a gun used by Angry Eddy.
Successfully complete one of the following tasks to get a trophy: