Probably the most known genesis game of all time, as well as possibly being the most known Sonic game of all time, Sonic 2 is well deserving. This was actually the only game I owned for years when I was little, and it kept me busy! I still play it quite alot. My Genesis is still working, but I also have it on Sonic Mega Collection (which is how you'd play this game if your Genesis doesn't work). Sonic 2 is probably the best classic Sonic game (I just wish Tails could fly here), and is pretty much what defined that series in the first place: High speed action and frantic gameplay requireing good reflexes. You can either play as Sonic or Tails, or, you can play as Sonic and have Tails follow you around and mimic your moves, which can come in handy in bosses. Its much more effective, however, if you have a friend control Tails with a second controller. The fustrating thing about that is that the screen still scrolls with Sonic, the player controlling Tails will often get left behind and not reapear for a few moments. It also has a decent 2 player mode. This game is just about right challenge wise and is great for any age. And, in my opinion tottaly beats any classic Mario game hands down! Terrific classic game, an absolute must have if you're a Sonic fan!