The Mystery of Sonic 3

You can stack multiple Sonic and Knuckles cartridges. Michael Jackson made all the music for it, every single chain. There are literally no other factors preventing you from piling up Sonic and Knuckle and reaching the moon. It was just a sort of bad MIDI that they had on the PC version, isn't it? I'm rather fond of the prototype music. When it was brought over to Sonic Origins they kind of screwed some of it up by re-orgustrating it when the only really needed to have cleaned it up in my opinion.