Shadow the Hedgehog is a recurring character in Sonic Speed, being one of the main antagonists of season six however became an anti-hero. He is a black and red hedgehog and the arch-rival of Sonic the Hedgehog, with his purpose of being created was to provide ways to develop cures for incurable deadly illnesses but was deemed a threat to humanity. Initially, Shadow sought to destroy the earth to avenge Maria Robotnik, but was convinced to help save it instead.