Rhythm Tengoku Gold. (Rhythm Heaven)
It is so hard to beat all the 50 Rhythm games,
Then you have reward system for how well you do in each of them,
A "Try Again" rating (Worst)
An "Ok" rating (Good Enough for moving on to the next game)
A "Just Ok" rating (Good Enough to move on but close to Superb)
A "Superb" rating (Good Enough to move on but how amazingly you did rewards you with a Medal)
After completing a game on with a Superb rating sometimes you get a chance for you to collect a Perfect Status for a Game you get 3 chances to do it before you have to wait for another one.
A "Perfect" rating (Requires you to do everything in a game completely Perfect when the chance comes around netting you a sweet prize)
Heres a video of one game:
http://www.youtube.com/watch?v=-71V-17sdyQ