- This is about the objects known as the "artifacts." For the episode, see Artifact.
The artifacts are two deceptively worthless objects that are the main focus of the Sonic Underground episode "Artifact". Consisting of a missile and a bomb, they were first discovered by Doctor Robotnik, who believed that they originated from the sacred city of Mobupinchu. However, they are actually dangerous warheads from a Mobian war, only a few centuries old. Robotnik's experts lied to him that they were valuable relics from Mobupinchu, and Robotnik took advantage of this by attempting to sell them for enormous sums of money to strengthen his reign over Robotropolis.
As a means of raising money to build more Swatbots, Doctor Robotnik introduced these artifacts at an aristocratic party and attempted to sell them in an auction, with the bidding starting at 100,000 Mobiums. The guests were shocked at this gargantuan price, but Robotnik warned them that anyone who refused to bid would be suspected of being a seditionist. Bartleby managed to acquire the missile for one million Mobiums, a price Robotnik was disappointed with. Disguised as waiters serving snacks at the party, Sonic, Sonia and Manic were horrified that Robotnik was raiding Mobupinchu and selling its treasures to fund Swatbot creation. Sonic then disrupted the auction as Sonia snatched the missile from Bartleby and Manic hid the orb in his fanny pack, and the three hedgehogs made off with the artifacts.
The hedgehogs had to find the location of Mobupinchu so as to prevent Robotnik from looting it, so Sonic and Sonia took the missile to Mobius University, where Sonia's old professor had it examined with the Gamma Spectrum Analyzer. It turned out that the artifact was really an old shell case from an ammunition disposal, and not from Mobupinchu. Meanwhile, Manic had sold his orb to a dealer called Vince so he could raise money for the Resistance, and when Manic learned from Sonic and Sonia that the orb was actually a bomb, the hedgehogs confronted Vince so they could buy it back. However, Vince revealed he had already sold the orb to Bartleby.
Vince informed Sleet and Dingo that the hedgehogs were out to retrieve the orb from Bartleby. Sleet and Dingo then showed up at Bartleby's mansion and kidnapped him and his orb before the hedgehogs could stop them. The bounty hunters took Bartleby to the excavation site where Robotnik was waiting to punish him, but the hedgehogs pursued them and rescued the orb. The bomb shortly exploded, destroying most of Robotnik's machines and activating several other warheads buried in the surrounding area, devastating the area completely.