Press Left(5), Up(5), Right(5), Down(5), Select(5) at the title screen. All
levels and bonuses will be unlocked. To access the sound test, hold A and
press Left or Right to make a selection, then press Select to hear it.
Select the "Scrapbook" option to view background information about the game.
View ending sequence:
Enter staff as a case-sensitive name. Enter the snack shop to view the
ending sequence. Note: This also unlocks the hidden credits level. Quickly
jump twice to get on top of the low building that appears immediately
before the programmer's credit. Then, jump up and keep jumping to the right
on the clouds until you find a hidden message.
Enter xyzzy as a case-sensitive name. Then, hold A and press Select to
increase the medal count to 400. Hold A and press Select again to reset the
count to 0.