At the main menu, highlight the "Tripod Select" option. Then, hold X + Y and press Up, Left, Down, Right(2), Up, Down, Right.All power-ups are triple missiles
Enter "MISSI" as a code.All power-ups are turbo rams
Enter "TURBO" as a code.Turbo ram auto-pilot
Enter "AUTOM" as a code.Invisible Tripods
Enter "GHOST" as a code.CPU controlled bonus Tripods
Enter "HUND" as a code.Alternate sound effects
Enter "RETRO" as a code.Debug mode
Enter "JOHNM" as a code.