Sonic Rivals 2 has improved nice.
I will tell you the good and the bad thing of Sonic Rivals 2.
Good:
+ 8 players to play, not 4 for story mode in Sonic Rivals (5 in quick play).
+ 13 course brand new.
+ Can find out how to unlock cards and suits.
+ New battle mode is nice
+ And the power ups, the boss etc, are so much fun.
Bad:
- Some cards are unlock by doing mutiplayer (which is trouble for those who play single play usual).
- And story mode finish very quickly.
But take away the bad points away and this game will be the best Sonic game on the PSP.
I highly recommend you to buy this.