Conflict Zone

Instant 10,000
Pause the gameplay then enter X, Left, Right, Up, Left.
After you entered, you will see a message.

100 population
Pause the gameplay then enter X, Right, Right, Left, Up.
After you entered, you will see a message.

Replay Missions
Pause the gameplay then press START then enter X, Up, Up, Left, Right, Left.

Mission Skip
Pause the gameplay then press START then enter X, Up, Up, Left, Right, Left.
You jumped to the end of the stage, press X at the debrief screen.

Invincible Units
Pause the gameplay then enter RIGHT, LEFT, RIGHT, RIGHT, X.

Fast Building
Pause the gameplay then enter X, DOWN, DOWN, UP, LEFT, RIGHT.