Haha very cool!
Nice work, very retro sounding! There are a few spots that don't sound quite authentic to me. The latter parts start sound like candy trance/pop that was ported to the Nintedo system. I'm not sure if that's what you were after, but you may want to simplify parts of it to give it a more genuine feel (I'd look at 0:30 onward).
All in all great work, very fun idea!
5/5
If you have the time, I'd love your input on my latest track, ST Suspense!