Invisibility:
Press Y, A, B, X(2), Left during game play. A message will appear at the top of the screen to confirm correct code entry. Repeat the code to disable its effect.

Slow motion:
Press Y, A, B, X(2), Right during game play. A message will appear at the top of the screen to confirm correct code entry. Repeat the code to disable its effect.

Fast motion:
Press Y, A, B, X(2), Down during game play. A message will appear at the top of the screen to confirm correct code entry. Repeat the code to disable its effect.

Flymo ragdolls:
Press Y, A, B, X, B, L during game play. A message will appear at the top of the screen to confirm correct code entry. Repeat the code to disable its effect.

Invincibility (PAL version):
Press Y, A, B, X, B, Right during game play. A message will appear at the top of the screen to confirm correct code entry. Repeat the code to disable its effect.

Bonus level:
Successfully complete the game under the Rebel or higher difficulty setting to unlock the Liberty Island level.

Submachine gun, miscellaneous items:
Press Y, A, B, X, Y, L during game play. A message will appear at the top of the screen to confirm correct code entry. Repeat the code to disable its effect.

Sniper, miscellaneous items:
Press Y, A, B, X, Y, Right during game play. A message will appear at the top of the screen to confirm correct code entry. Repeat the code to disable its effect.

Rocket launcher, miscellaneous items:
Press Y, A, B, X, Y, Left during game play. A message will appear at the top of the screen to confirm correct code entry. Repeat the code to disable its effect.

Heavy machine gun, miscellaneous items:
Press Y, A, B, X, Y, Down during game play. A message will appear at the top of the screen to confirm correct code entry. Repeat the code to disable its effect.

Shotgun, miscellaneous items:
Press Y, A, B, X(2), L during game play. A message will appear at the top of the screen to confirm correct code entry. Repeat the code to disable its effect.

Nail gun:
Press Y, A, B, X, A, Left during game play. A message will appear at the top of the screen to confirm correct code entry. Repeat the code to disable its effect.

Unlimited ammunition:
Press Y, A, B, X, A, Right during game play. A message will appear at the top of the screen to confirm correct code entry. Repeat the code to disable its effect.

Cycle through spawn points:
Press Y, A, B, X, A, L during game play. A message will appear at the top of the screen to confirm correct code entry. Repeat the code to disable its effect.

Maximum charisma:
Press Y, A, B, X, A, Down during game play. A message will appear at the top of the screen to confirm correct code entry. Repeat the code to disable its effect.

Liberty Island mission: Programmer message
At the end of the level, enter the head of the Statue of Liberty to see a programmer message in lights.

Thin Ice mission: Kill your own soldiers
Your first objective is to destroy the ventilation shaft so that your troops can roll up inside. After you complete the objective, send one of your troops to the middle of the destroyed fans. Then, throw a grenade at them. Some will just duck and when the grenade explodes; they will fall down and die.

To kill your own soldiers on this level, simply order one of them to go to the edge of the ice. Then either throw a grenade by him, or go over to him and punch him. Eventually he will fall in the water and freeze to death. The best way may be to get a rocket launcher (enable the code if needed) as well as the "Flymo Ragdoll" code. Shoot the rocket near the man. He will fly in the air then fall into the water. It will take him a long time to get up, but when he does he automatically dies.

Go to the edge of the level and tell your people to defend. Step back and enable the "Rocket launcher" code. Shoot them and they will fall into the water and die.

Defeating General Tatarin
To easily kill General Tatarin on your first trip to Governors Island, sneak down to where you have to go right over all the barriers. Take out those troops and look for a wall that is shorter than the buildings beside it. Try to look over the barrier to see a basement entrance. Then, look for a window that has a light behind it. Enable the "Rocket launcher, miscellaneous items" code. Fire at the window and the "Killed Tatarin" message should appear. Then, run away quickly. Alternately, walk down the same way, but get on top of the crates. There will be a guardrail where the first fence segment ends. If you are lucky, you can jump to it, climb the rail, and find the door. You will fight various opponents and finally the General. If you enable the "Blind Enemies" code, it will be a lot easier, and you can kill General Tatarin with any weapon.

Hair length
While playing the game, notice that Chris' hair gets longer with every mission.

3600 round machine gun
At any level before the stage where you have to kill General Tatarin, go to the rebel base. Go in circles around it to find a machine gun that has 3600 rounds.