In the Sonic movie world, we’ve come to learn that our speedy, anthropomorphic heroes are actually aliens from other planets. This background becomes more interesting with Shadow the Hedgehog, who, as revealed in the game, has some alien DNA. However, when Shadow first appeared in Sonic Adventure 2, he was portrayed as an artificially created being by humans. Sonic 3 embraces the alien angle entirely, unveiling that Shadow was discovered half a century before the film’s events when a strange meteorite crash-landed on Earth. Upon investigation, the GUN forces uncovered Shadow and began conducting experiments on him in a secretive Earth-based facility, rather than the Space Colony Ark orbit as depicted in the games.
In the games, Shadow’s origins are layered with complexity. Frankly, it’s no shock they streamlined his backstory for the film’s shorter format. In Sonic Adventure 2, we discover Shadow’s roots as a creation of Gerald Robotnik, Eggman’s grandfather, intended to be the Ultimate Lifeform with the key to immortality. Come Shadow the Hedgehog, things take a turn when it surfaces that Gerald, in sheer desperation, allied with Black Doom, an alien overlord, incorporating some of Doom’s DNA into Shadow’s making. In exchange for this aid, the plan was for Shadow to aid Black Doom and his alien army in their conquest of Earth. In Sonic 3, Shadow remains clueless about his true origins, leaving room for the Black Arms to possibly make an appearance in future films as his backstory unfolds. Interestingly, Gerald Robotnik isn’t credited with creating Shadow in this version; rather, he led the team investigating him following his celestial arrival.