Sonic Underground

Sleet and Dingo escape the Flying Fortress with the Chaos Emerald. In a fight over who will control the Emerald's power, Sleet and Dingo drop and break the Emerald in two. Instantly, a rash of earthquakes and other natural disasters are sparked by the emerald's energy. Knuckles and the Hedgehogs turn to a relative of Knuckles for answers of how to stop Mobius from being slowly devoured by the emerald's force.