The Hedgehogs steal historical artifacts of Mobuis from Robotnik before he can pawn them off at an auction. Sonic and Sonia take one of the pieces to a university professor who informs them that the artifact is actually a bomb from the Mobian war. While his brother and sister are discovering the artifacts origin, Manic, sells his piece to a black-market salesman for cash, who then sells it to Bartleby, and suddenly a bomb has fallen into innocent hands. The Hedgehogs must act fast to retrieve the bomb and protect the treasure that is the key to Mobius past.
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