Sonic Underground (1999)

S1E13 Artifact

The Hedgehogs manage to snatch away some historical treasures from Robotnik just before he intends to sell them at an auction. Sonic and Sonia bring one of the artifacts to a university professor, who reveals that it’s actually a bomb dating back to the Mobian war. With urgency, the Hedgehogs realize they need to recover the bomb and safeguard the precious piece that holds the secrets of Mobius's history.