Max power mode
Swiftly press L1, R2, L2, R2, L2, Triangle, Circle, Triangle, Circle, then hold L1 and press Start at the "Press Start" menu to access max power mode. The sound of a gunshot will verify proper entry. Max power mode allows you to start with all weapons and unlimited ammunition. Note: The code must be entered before demonstration mode starts.

Sudden death mode
Swiftly press L2, R2, L2, R2, Circle, Triangle, Circle, Triangle, then hold L1 and press Start at the "Press Start" menu to access sudden death mode. The sound of a gunshot will verify proper entry. Note: The code must be entered before demonstration mode starts. Sudden death mode allows opponents and your character to be killed with one hit. Or swiftly press L2, R2, L2, R2, Triangle, Circle, Triangle, Circle, then hold L1 and press Start at the "Press Start" menu.

All multi-player characters
Swiftly press Up, Down(2x's), Right(3x's), Left(4x's), then hold Circle and press Start at the "Press Start" menu. The sound of a gunshot will verify proper entry. All the Bosses as well as the engineer and a few army characters will be unlocked in multi-player mode. Most of the Bosses have odd guns and may not be able to back up against walls or roll. Or finish the game under the easy and normal difficulty settings. Note: The code must be entered before demonstration mode starts.

After all characters are active, all of the middle row characters have special weapons (unlimited ammunition, but cannot place back toward wall), and Dan has a special pistol.

Trial mode
Swiftly press Up, Down(2x's), Right(3x's), Left(4x's), then hold Triangle and press Start at the "Press Start" menu to access trial mode. The sound of a gunshot will verify proper entry. This mode allows any level in the game to be played. Note: The code must be entered before demonstration mode starts.

Max power, sudden death, trial modes
Finish the game under the hard difficulty setting to access max power, sudden death and trial modes.

Killing machine gunner
When someone is behind a machine gun, take out your missile launcher and aim over the machine gun.

Stage 10: Lasers
On stage 10 you have to negotiate four moving lasers by rolling under them. When you reach the last laser, an FMV sequence starts, showing a guard switching the wall laser back on so you cannot go through the door on the other side. You would normally have to go back again, switch it off and then re-negotiate the lasers to get back to the door. To skip this, pick up the C4 explosive in the room where you locate Tom. When you switch off the wall laser before the obstacle course, press Down to lay the C4 by it, then do the run. As you reach the last laser and the FMV sequence starts, press Down to detonate the C4. If done properly, you will hear a howl. This kills the guard before he can switch the wall laser back on. Then you only have the last one to get under. Also in any similar laser situation, have the handgun in hand. You will be less likely to clip the laser.