Bonus level
Successfully complete the game with the best ending. Allow the credits to complete and an intermission sequence will begin.
Evac level
Use the following tactic in the Evac level where you have to drive a truck. Go to this grid code to join the Guerillas Fia EA64. On the map there will be a code 113. Drive your truck there. An intermission sequence will appear, then the level will end. You will be a hostage for the Soviets. Stay in the tent on the next level until the Russian that is guarding you dies. Then, go outside and one of the guerrillas will talk to you.
Christmas trees
Set the system date to December 25 and start the game. All of the pine trees will be covered with decorations and have presents under them.
Invincibility (demo version)
Before the end of the level, just when the helicopter picks you up, wait about five seconds. Then, go to your action menu by pressing ] or [ and select "Eject". Press [Enter] and your character will parachute out of the helicopter. When he lands, you can continue the game and not get killed.