You are trained to serve freedom loving citizens by taking the fight to the enemy. You do so in secret, for discovery is death. You have trained to see, to hear, and to transmit one message to your enemies -- that they are unwelcome, and their actions unsupported by the rest of the free world. You have gotten the best in training, in equipment, and in intelligence, but on the field, things can happen (such as the killing of you ... by us ... online) but stick with IGN and we will guide you through the difficult parts of your assignments.

Get the guide here.

On the main menu, press START to access the Campaing, Custom Mission, Split Screen, etc. choices. Enter L1, R2, L2, R1, D-PAD LEFT, D-PAD RIGHT, SQUARE, CIRCLE.

You should be able to select any map in custom mission mode (and play the practice missions on any difficulty).