Shadow the Hedgehog (シャドウ・ザ・ヘッジホッグ, Shadō za Hejjihoggu) is the former adversary turned deuteragonist(next to Miles 'Tails' Prower) from the Sonic the Hedgehog series who, like Knuckles, has a rivalry with Sonic which has evolved to a more intense rivalry. He is known as the "Ultimate Lifeform." He has his own game that mainly features him, the self-titled Shadow the Hedgehog, which was released in 2005 for all three sixth-generation consoles (except the SEGA Dreamcast, which was discontinued before Shadow the Hedgehog was planned). Since his debut, he consistently holds second place as the most popular character in the franchise, trailing the obvious Sonic. Unlike his heroic counterpart, Shadow is a much darker and developed character, willing to do whatever it takes to reach his goals. However, in the recent games, he has become a somewhat lighter, anti-hero character.
Shadow the Hedgehog first appeared in Sonic Adventure 2 as one of the main antagonists. He matched Sonic in speed using his infamous skating technique to run. In his debut game, Shadow attempts to frame Sonic for crimes he did not commit and spends the rest of the adventure chasing him down as Sonic tries to stop Eggman from using the Space Colony ARK's main cannon to destroy Earth, and assists in Gerald Robotnik's revenge scheme against humanity partly for the death of Maria Robotnik, a close friend of Shadow's. Towards the end, he is presumed dead after an incident at the Space Colony ARK. At the beginning of Sonic Heroes, he is discovered in a stasis module in an abandoned factory and awoken by Rouge the Bat. Shadow then forms Team Dark with Rouge and E-123 Omega, who all strive to get revenge on Doctor Eggman for their own reasons. From then on, although he remains a strong rival to Sonic, he is sometimes forced to ally with him to take on a much greater threat.
Shadow appears as an unlockable Assist Trophy character in Super Smash Bros. Brawl. He uses his "Chaos Control" ability to slow down everyone except the summoner, similar to the effects of the Timer item, though with a shorter duration. Shadow the Hedgehog is unlocked when Sonic is unlocked as a playable character. He also appears as a regular Trophy.
In Brawl, Shadow the Hedgehog is voiced by Jason Griffith in the English version of the game (who also voices Sonic), and Kouji Yusa in the Japanese version.
- Shadow The Hedgehog is a black hedgehog who resembles Sonic. He was created by Dr. Eggman's grandfather, Gerald Robotnik, to be the ultimate life-form. Not only does he look like Sonic, but he has equal abilities. He has great skill with the space-time warping technique called Chaos Control. To reach his goals, he'll use any means necessary.
- Sonic Adventure 2 Battle
- Sonic Heroes
- Shadow the Hedgehog
Shadow returns as an assist trophy in Super Smash Bros. for Nintendo 3DS and Wii U, reusing the same ability.
Engineered to be the ultimate life-form by the brilliant Professor Gerald Robotnik, this black hedgehog appears very much like Sonic. He has a dark side, however. In Smash Bros., he uses Chaos Control to warp space-time, slowing every fighter down except the player who summoned him.
Shadow returns as an assist trophy once again in Super Smash Bros. Ultimate. He is functionally identical to the previous games; the only difference is that he uses a Chaos Emerald during Chaos Control he can not only slow other fighters down he can also freeze them in place for a couple of seconds.
- In Super Smash Bros. Brawl, Shadow was voiced by Jason Griffith (who was also the voice of Sonic), However, in Super Smash Bros. for Nintendo 3DS and Wii U he is now voiced by Kirk Thornton, who has voiced him in the Sonic series since 2010 with Sonic Free Riders.
- Shadow was one of the highly expected characters for Super Smash Bros. Ultimate. Fans believed that Shadow was to make a playable inclusion in the game as an Echo Fighter for Sonic the Hedgehog considering the fact that Knuckles is an Assist Trophy. He has been shown in many "leaks" which says Shadow the Hedgehog will be playable, however at the November 1, 2018 Direct of Super Smash Bros. Ultimate, Shadow was announced to make his return as an Assist Trophy, which caused a minor disappointment from the fans.