This is the first Sonic game to be based on a cartoon, as all the opponents are from Adventures of Sonic the Hedgehog.
The game has a sound test menu that is only accessible if played on a Japanese Mega Drive. However, the game was a Western release only, so the only way to access this is with a hacked system that bypasses the region lockout.
The game is actually simply a modified version of the Japanese only release "Puyo Puyo". The first training levels of Puyo Puyo were removed from the game, but they can be put back in through hacking. If this is done, the Puyo Puyo characters Skeleton T., Nasu Grave, and Mummy are replaced by a character that has the intro of Coconuts with the mugshot of Scratch.