This is a fight between heroes and villains - will you save the world or conquer it? The search for the Chaos Emeralds continues, and a front line has been drawn between Hero and Dark. Experience two unique adventures featuring famous heroes and new and returning villains. It's time to start the battle that will determine the fate of the world! Save the world as the heroes of Sonic, Tails and Knuckles, or wreak havoc as Shadow, Dr. Eggman and Rouge. Use their unique skills and abilities! Leave the main story behind for a moment and challenge a friend in two-player mode - take part in card races or other competitive modes! Train your pet, Chao, develop his stats, and use his skills in unique mini-games! Take on 150 unique missions across 30 action-packed stages!