With a storm raging against Angel Island, Sonic and his friends are in a fight for their lives! Trapped underground and separated from his friends, Sonic finds himself face-to-face with�wait�that�s not Amy?As something terrifying happens beneath the ground, on the surface, Knuckles and Tails brave the violent storm ripping through Angel Island�although they have their own foe to deal with.Can our heroes persevere through the chaos and keep everyone safe? Or will these mysterious figures claim another emerald�or even a life?