Nicktoons Racing

Various Nickelodeon characters each receive a letter invitation to compete in a Grand Prix for the top prize, the Krusty Krab Big Bun Award. The host of the competition, also the individual who sent the invitations, is an unknown, unseen driver of a sleek, black car with a tinted dome window simply dubbed as the Mystery Rider, which the participating racers are challenged to beat, as well as each other. (wiki)