Cheats
Plug controllers into both PlayStation ports before you boot the game. Hold down Start on controller two (the right one) while the game loads. Press L1, R1, R2, L1, Select, and Start at the main menu or while gameplay is paused to enable the cheat mode. The following cheats may now be entered during gameplay:

Cheat: Result *
Press Select on controller two: skip level
Press Triangle on controller two: God mode
Press Circle on controller two: infinite power
Press X on controller two: gain all items

Biggest Bang
For transport missions, you need to pack the biggest bang into the smallest number of units. Choose your most experienced units, even if they aren't packing your most powerful weapons.

Leave Some Units
Be sure to leave some units near your base to defend it. After you've completed a mission, your next mission begins with your units in their final locations. If all your units are a long way from your base, and the next scenario begins with your base under attack, you're in trouble.

Combine Them
It's not a good idea to have the same type of weapon on all of your units. Combine the types of weapons in each group to make sure they can handle different threats.

Cheat mode
Press and hold Start on controller two while the game loads. Then, press L1, R1, R2, L1, Select, Start at the main menu or while the game is paused to enable cheat mode. Press the following buttons on controller two for the different cheats:

God mode:
Triangle

Unlimited power:
Circle

Level skip:
Select

All items:
X

Super unit strength:
Up

Weak unit strength:
Right

Current research completed:
Down

Additional structures:
R1

Additional units:
R2