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Press Start while playing, then hold R1 + R2 + L1 + L2 and press X, Right(2x's), Left, Up. A message at the bottom of the screen will verify entry.

Press Start to pause the game, then press X, Right(2x's), Left, Up. A message at the bottom of the screen will verify entry.

Faster construction
Press Start while playing, then press X, Down(2x's), Up, Left, Right. A message at the bottom of the screen will verify entry.

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Press Start while playing, then hold R1 + R2 + L1 + L2 and press X, Left, Right, Up, Left. A message at the bottom of the screen will verify entry.

Or you can press Start to pause the game, then press X, Left, Right, Up, Left. A message at the bottom of the screen will verify entry.

All view
Press Start while playing, then hold R1 + R2 + L1 + L2 and press X, Left(2x's), Right, Left. You may need to redo this code until the confirmation message is seen. This code will allow you to see all enemy units and buildings.

Mission skip and replay
Press Start while playing, then hold R1 + R2 + L1 + L2 and press X, Up(2x's), Left, Right, Left. You may need to redo this code until the confirmation message is seen. After that, leave your game. When you reach the debriefing screen, press X to advance to the next mission. You can also enter the replay menu to have every mission available to be played again. Note: This code will not work with the bonus missions.

Hints & Tips

Mission 4: Releasing Hooper from prison
Manage to get one of your commandos into the prison. The prison will then explode, and your commander will still be standing there. Take him to the northeast village and bypass the GHOST troops.

When you wish to save Hooper from prison, take two Commandos, one Tank, one Mobile Artillery, and two Bazookas. Send the other troops to the outpost by the right slope to get on top of the hill. Wait until they start blowing it up. Then, take the men you held and proceed to the base. Blow up the prison with the Commandos. There will be no men or machine gun on the bunkers. Then, send him to the flag at the northeast village. Do not worry there will be one or two men, but Hooper is strong and will make it without even fighting.

Attack quicker
First build structures that make units (Barracks, V. Factories, etc.), then have each of them make units. For example, if you made two Barracks and told one to make fifteen soldiers and the other to make fifteen soldiers, both barracks will make them. This works for both IPC and GHOST. This trick will allow you to make soldiers and attack quicker.