He is an anthropomorphic hedgehog/Black Arms hybrid and the arch-rival of Sonic The Hedgehog. Shadow was created as the "Ultimate Life Form" by Gerald Robotnik, using the DNA of Black Doom, and is the end result of Project Shadow. His purpose was to provide ways to develop a cure for incurable fatal illnesses, more specifically for Gerald's granddaughter Maria Robotnik, but he was captured and put into stasis by the military when he was deemed as a threat to humanity. Jason And Kirk Is Fine, but your own take is welcome as well!