Oh man, I remember that the original NES version had this security feature midway through where you had to soak this envelope that came with the game in water, and enter this code that appeared. I remember some puzzle involving a pipe organ, and piloting a submarine an archipelago looking for dive spots and such. I also remember a whale escape level, and a section where you had to disguis yourself as a girl to get a better yoyo weapon.
Incidentally, years later I bought a huge, heavy wooden yoyo because it reminded me of the game and triggered some nostalgia.
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Your boos mean nothing, I've seen what makes you cheer.
- Rick Sanchez