Both Eggman and Sonic’s gang have located the last two chaos emeralds.  Unfotunately, they are onboard a heavily guarded Metarex space fortress. Eggman proposes a little teamwork: Members from each group will enter the fortress and disarm the security system. After that, it's a race for the prize, finders keepers! Sonic and the gang agree, and Chris joins Shadow and Rouge on a mission to disarm the alarm. They're successful and both teams set off for the emeralds. Sonic's gang easily takes the lead, but Eggman has some dirty tricks up his sleeve. When they finally reach the emeralds, they find the Metarex are using them for their evil plans. Before they know it, our heroes come face to face with Dark Oak himself, the ruler of all the Metarex!