Terrorist weapons
Successfully complete the game with a rank of ''Ensign'' to unlock terrorist weapons in the armory in single player mode.

Unlock Level Select
Beat the game on Lieutenant JG difficulty to unlock level select.

Unlimited ammunition:
When playing the game, press R3 and you will reload your gun. You will not lose a magazine as when you auto reload.

Difficulty - Unlock:
Ensign - Terrorist weapons in SP
Ensign - Lieutenant JG difficulty
Lieutenant - JG Level Select
Lieutenant - JG Lieutenant difficulty
Lieutenant - Multiple Grenade Launcher
Lieutenant - Lieutenant Commander difficulty
Lieutenant - Commander Commander difficulty
Commander - Captain difficulty
Captain Rear - Admiral difficulty
Rear Admiral - Admiral difficulty

Head-Set Commands:
"Bravo open/close door"
Say while pointing at a door with your crosshair.

"Breech, Bang, Clear"
Say while pointing at an open door with your crosshair.

"Hands up, get down"
Sneak up behind a guard and say this.

"Team low profile"
Puts the team sneak mode.

"Bravo diffuse bomb"
Say while pointing at a bomb with your crosshair.

"Bravo, Snipe"
Bravo team will snipe all Tangos in view.

Mission 2:
At the beginning, tell your men to hold their position and go to the right, up the hill. Stay to the left side of the hill while ascending it. You will see an enemy fairly soon in the mission. Quietly and carefully snipe him. There will be another one very shortly after the one you just killed. Continue on the cliff and you will reach a drop off to another cliff. Jump down. Walk slowly to the edge or close to it until you can see the small cabin. Snipe the man standing outside quickly with one or two shots. Then, tell your men to regroup after you jump down from the cliff and go to the cabin. There will be one or two men inside -- kill them quickly. Keep moving north -- that is where all the action is located. Objective 1: You will find the Intel in the big place with the bridge-type object on the third floor. It is in the laptop. Objective 2: The weapon caches are the boxes stacked on top of each other. Put C4 on those and that will do the job. Objective 3: As one of the secondary objectives, blow up the generator with C4 as well.