Sonic the Hedgehog protagonist Sonic the Hedgehog, a blue hedgehog able to run at supersonic speeds, and recurring villain Dr. Eggman, an evil scientist whose ambition is to conquer the world. Among Sonic's many allies, the most well-known include: Miles "Tails" Prower, a twin-tailed, highly intelligent yellow fox who is Sonic's sidekick and best friend; Amy Rose, a pink hedgehog who is Sonic's self-proclaimed girlfriend and a hero in her own right; Knuckles the Echidna, a coolheaded red echidna who is the guardian of the Master Emerald; Shadow the Hedgehog, an anti-heroic doppelgänger of Sonic with a dark past; and Metal Sonic, a
Sonic the Hedgehog (2006 video game) appearances since. Silver is a playable character in "Sonic Rivals" (2006) and its sequel, in "" (2007), and in "Mario & Sonic at the Olympic Winter Games" and its sequels, and is a minor character in the Nintendo DS version of "Sonic Colors" (2010) and "Sonic Forces" (2017). He also appeared in the "Sonic the Hedgehog" comic book series published by Archie Comics. The main theme of "Sonic the Hedgehog", "His World", was sampled in Drake's 2017 song "KMT". To celebrate the "Sonic" franchise's 20th anniversary in 2011, Sega released "Sonic Generations", which remade aspects of past "Sonic" games. The