Press Select during the game to bring up the Option menu. Highlight Key Config. and press u. At the Key Config. menu, hold R1 and press square, square, square, square, square, square, square, square, square, square. If you entered the code correctly, the word "Manual" in the middle of the screen will turn red. Resume gameplay, and you will have unlimited ammunition for any weapon that you pick up. This code also works for the Hunk and Extreme Battle mini-games.
Anthony Driver, Jr.
Hayward, CA