Shadow the Hedgehog is a character from the Sonic the Hedgehog series. He is an anthropomorphic hedgehog/Black Arms hybrid who resembles Sonic the Hedgehog in many ways and serves as an occasional rival of his. Shadow was created as the “Ultimate Life Form” by Gerald Robotnik by 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 deadly illnesses, more specifically for Gerald’s granddaughter Maria Robotnik, who he had a great bond with. However, he was eventually captured following his birth and put into stasis by G.U.N. when he was deemed as a threat to humanity.

Fifty years later, Shadow was released by Dr. Eggman in order to enlist him in his plan to conquer the world. Initially, Shadow worked with him but secretly sought to destroy the planet in order to avenge Maria, who had been killed by the military, but was persuaded to save it from Gerald’s doomsday plans. In the process, Shadow lost his memories and as such, sought to uncover the truth of his past, during which he met Black Doom and the Black Arms; in the end, Shadow regained his memories, uncovered the truth, and thwarted Black Doom’s agenda and saved the world. From there, he continued his mission to protect humanity for the sake of Maria.