SynopsisIntroduced on SEGA Genesis in 1991, Sonic the Hedgehog rapidly became one of the world's most recognizable video game characters and franchises. Now, to celebrate his 15th birthday, Sonic is back exclusively on PSP in Sonic Rivals. Sonic, Knuckles, Shadow and the insidious Dr. Eggman are all back to trip, shove and vault each other as they race through their different stories to their finish lines at breakneck speed.SEGA brings back traditional 2D gameplay with new 3D tracks, traps, hazards and environments. Play as one of the characters against a rival in a race so competitive you'll think you are playing a real opponent. Or, play with a buddy for intense, multiplayer competition. Customize your character's skills by collecting trading cards, then challenge other players and wager them online. Welcome the beloved blue hedgehog back into action on your PSP system.