When 15 racers compete for 1 million bits, they go through a parody of Mario Karts and a whole bunch of levels, but only one racer will win. They shall go through dangerous worlds, even the human world, but who will come in first place?
The Mane Six get teleported to Equestria by a crazy machine to Hero Factory. Ridiculousness and seriousness ensues, with the mares having to help Alpha Team with protecting the galaxy! (Some more than others.)