Sonic Adventure [Online Game Code] An ancient evil lurking within the Master Emerald has been unleashed from its slumber by the devious Dr. Eggman and is on the verge of becoming the ultimate monster using the 7 Chaos Emeralds. Only Sonic and his friends are heroic enough to put a stop to Dr. Eggman and his evil minions. Hit the ground running in this classic epic adventure in a race against time to save the world!