While you are 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.