Start a game. Press Back during the game to display the main menu. Then, hold L and R, click Left Analog-stick and click Right Analog-stick, then quickly press White, Black, Black, White, White, and Black at the main menu. The cheat menu will appear, which contains "All Weapons" and "Refill" options. To access these cheats, press Back during gameplay and select the options you want at the cheat menu. Then, press Back to resume playing. Other cheat menu options must be unlocked during gameplay.