Head Animations - At the title screen select ''Options'' and press: C, A, Left, Right, B. You will hear ''NICE'' when you've entered the code correctly. Then press START to view the head animations.

Stage Select - When the title screen appears, press START once. Leaving the cursor at Start Game, enter the code: C, A, LEFT, RIGHT, B. If you hear a sound, you've got it! Press START and you'll access the Stage Select! Just choose your level and stage. Then press START to play! (Note: This trick was done on an early version of the game. It may or may not work on later versions)

Hard Mode (or 1-hit death mode) - At the title screen, press Start once, then leave the cursor on "Start Game." Just like the stage select code, press C, A, Left, Right, B. You will hear headdy say "Nice" when you've entered the code correctly. Then press and HOLD START. Continues holding start until you see the "Opening Demo" scene appear.

Now you can release the start button and continue as normal. Be warned, One hit is all it takes to kill you now.