Shadow is an anthropomorphic black hedgehog appearing in Sega's Sonic the Hedgehog series of platform games and its various spin-offs. He first appeared in the 2001 installment Sonic Adventure 2,[5] the final Sonic game released for a Sega video game console.[6] His roles in the games vary. Some, such as the main series games Sonic Adventure 2,[6] Sonic Heroes (2003),[7] and Sonic the Hedgehog (2006) feature him as a major playable character,[8] and he is the protagonist of the spin-off Shadow the Hedgehog (2005) and a downloadable content (DLC) package for Sonic Forces (2017).[9][10] Others, such as the anniversary game Sonic Generations (2011), limit him to a non-playable role.[11] In the games, Shadow is depicted as a mysterious, sharp-witted, and brooding antihero.[12][13][14] While his ultimate goal is to protect the world from danger,[12] he dislikes humanity,[15] and once he has set a goal, he does whatever it takes to accomplish it.[12] This often causes him to take risks without thinking them through and puts him at odds with series protagonist Sonic the Hedgehog.[16] Although a loner, Shadow collaborates with treasure hunter Rouge the Bat and robot E-123 Omega in games such as Sonic Heroes, Sonic the Hedgehog (2006), and Sonic Forces.[7][17] Shadow allies with Sonic in some games,[13] but also does so with Doctor Eggman in Sonic Adventure 2 and Shadow the Hedgehog.[9][18] Shadow shares many similarities with Sonic.[7] Visually, GameSpot's Ben Stahl described Shadow as "an evil version of Sonic himself—similar in appearance, but with darker skin, more angled eyes, and a fearsome snarl instead of Sonic's trademark grin."[5] GamesRadar+'s Justin Leeper said that if Sonic was Superman, then Shadow would be his Batman.[19] The characters control similarly in games, as both share skills and the ability to run at great speeds.[7][18][20] Shadow has unique attributes in some games, such as his uses of firearms and vehicles in Shadow the Hedgehog and Sonic the Hedgehog, respectively.[8][9] He can also use the Chaos Emeralds to perform "Chaos Control"—allowing him to distort time—and create weapons like spears.[7][12][15] Like Sonic, Shadow can transform into a "Super" form giving him special powers.[21][22