Dr. Robotnik has finally destroyed the world! A giant dark creature rises from the planet's core and plunges the world into neverending darkness. Meanwhile Sonic transforms into a night beast with beefy arms, the Werehog. He meets up with a small unsuspecting creature whom he calls Chip, and the two set out to put the world back together using the Chaos Emeralds, while battling monsters spawned from the Dark Gaia.
