This game is so much fun!  There are so many levels and they are all different.  After 2 levels you have to fight the boss: Dr. Robatnik.  The levels have there own unique enemy animals and bugs, all of which are killed by different methods.  You can power up and zip across the levels as you roll at lightning speeds.  There are bumpers and loop-de-loops scattered all across the levels.  This is a definite buy for owners of Genesis.  It is worth the [$$$].  You must buy!