
If you have a pair of Xbox Live accounts, you can try this technique. If one account is of a lower rank than the other, you can give the lower account an instant power-up when using both accounts to play. When you unlock something at the end of the game (such as the Overkill Perk), immediately log out of your account and sign into the lesser account. Head to the Xbox Live game lobby and press Y, and the game will have unlocked for this particular account whatever you unlocked with the first account.
Below is the level distribution list for Intel Pieces, which are enemy laptops full of information strewn throughout the game. There are thirty of them total. The left column is the level in question, while the right column is how many Intel Pieces can be found on that level. Levels with no Intel Pieces are excluded completely.
To unlock the following weapons in multiplayer mode, reach the numbered rank listed.
To unlock the following "Golden" weapons, fulfill the requirement listed.
To play an all-new mission, which is an extra mission after the main quest is completed, beat the game and view the ending credits thereafter. After they've run their course, you will then be given the opportunity to play one last single player mission before all is said and done.
The following works on the mission entitled "Hunted". After fighting your way through a basement (after going underneath a bridge, across a field, et cetera), you'll reemerge outside. A nearby house next to a vending machine and a car should be your target from here. Inside the house, there's a laptop on the table. This is a piece of Intel, and collecting all thirty of them in the game will unlock all of the Cheat options available. If you collect the Laptop, and then head through the nearby checkpoint, it will be permanently acquired on your save file. Kill yourself at this point (a Grenade is an easy way to do so), and backtrack to the house. Collect the Laptop again, go to the checkpoint, kill yourself, and repeat the process. By doing this, you can collect thirty laptops without actually collecting all thirty of them. (unverified)
To unlock Prestige Mode, which is a multiplayer-only mode, you must reach experience level fifty-five. Instead of capping out at level fifty-five, which is the highest level, Prestige Mode allows you to start again from level one. This can be done a total of ten times, giving you ten different icons in in-game lobbies to show your extreme achievement.
To unlock Arcade Mode, beat the game once through on any difficulty level. Arcade Mode itself is split into two options - Full Challenge or Level Challenge - that add extra replayability to the game.
Cheats are unlocked not by inserting passwords, but by acquiring the thirty Intel Pieces strewn throughout the game. The more of them you collect, the more cheats you can access. On the left are the number of Intel Pieces collected, and on the right are the cheats that are unlocked, with an explanation of what each does.
To unlock Prestige Mode, which is a multiplayer-only mode, you must reach experience level fifty-five. Instead of capping out at level fifty-five, which is the highest level, Prestige Mode allows you to start again from level one. This can be done a total of ten times, giving you ten different icons in in-game lobbies to show your extreme achievement.
To unlock Arcade Mode, beat the game once through on any difficulty level. Arcade Mode itself is split into two options - Full Challenge or Level Challenge - that add extra replayability to the game.
Below is the level distribution list for Intel Pieces, which are enemy laptops full of information strewn throughout the game. There are thirty of them total. The left column is the level in question, while the right column is how many Intel Pieces can be found on that level. Levels with no Intel Pieces are excluded completely.
Cheats are unlocked not by inserting passwords, but by acquiring the thirty Intel Pieces strewn throughout the game. The more of them you collect, the more cheats you can access. On the left are the number of Intel Pieces collected, and on the right is the cheat that unlocks, with an explanation of what it does.