Scratch and Grounder build their own robot, a naive over-grown kid called "Robot". When Robot runs off with Robotnik's new invention, the Super Planetary Implosion Module (SPIM), capable of impoding huge parts of Mobius out of existence, the race is on to catch him, over all kinds of Sega terrain; mountains, caves, lava pools, rivers, oceans, snow and ice. Robot's homing device leads him back to the Fortress, but before he can press the button on the SPIM, Sonic and Tails rewire it to make the Fortress implode into the size of a shoebox.
Sonic the Hedgehog, the most fearless hero on Planet Mobius, uses his supersonic speed and teenage irreverence to thwart the comedically despicable Dr. Robotnik. Sonic’s idolizing little buddy, Tails, tags along on every fast-action, gag-driven adventure.