Enter "TheWorldIsMine" as a case-sensitive code to unlock all maps.
Enter "CarvErVitrUvian" as a case-sensitive code. Note: This code does not work in the retail version of the game.
Enter "BulletsofHell" as a case-sensitive code.
Enter "VitruviAnRush" as a case-sensitive code.
Enter "GiveMeHealth" as a case-sensitive code.
Enter "AmAFastMachine" as a case-sensitive code. Note: This code does not work in the retail version of the game.
Enter "PunchMeHard" as a case-sensitive code.
Enter "NotForSissies" as a case-sensitive code.
While in the map maker, hold L + R + Y + B + X + click and hold Left Analog-stick + Right Analog-stick and press A. The message "MtP! Maki! Naru! Mayu! Aki!" in Japanese will appear.
When "Press Start" appears at the title screen, press A instead, and you will be taken directly to the main menu without playing the game play movie.
When the final battle begins with General Crowe, make sure you have a lot of grenades and the assault rifle with the grenade launcher equipped. General Crowe will not fight person to person at first, so focus on the monsters jumping around. Note: Do not fire the helicopter's rocket launcher; you will need it for when you fight Crowe. Use the helicopter to shield yourself from Crowe's machine gun fire. Use the grenades with good accuracy to kill the monsters. Try to get two of them at the same time if possible to save grenade rounds. At some point they will stop dropping down. Once this happens, focus on Crowe. After some time of shooting at him, he will jump down and fight you person to person. Avoid his machine gun, as it takes a lot of your health away. It is recommended that you use the speed ability to dodge bullets and hide behind objects to regenerate health. When Crowe gets in front of the door, use the helicopter's rockets.