The Metal Sonic Series are a group of robots created by Dr. Ivo "Eggman" Robotnik in order to give himself a robotic version of Sonic the Hedgehog, whom these robots are primarily designed to contend with.
After having a number of his operations thwarted by Sonic, Eggman decided to try fighting fire with fire by creating the Metal Sonic series. The first known robot in this line was Silver Sonic, a prototype version of which was unleashed against Sonic after Breezie the Hedgehog betrayed him. When that robot failed, Eggman soon developed the namesake robot of the series, Metal Sonic. This robot similarly failed to defeat Sonic, leading Eggman to create a number of alternative designs. These included a second version of Silver Sonic, Mecha Sonic, and even Titan Metal Sonic when the original version failed to defeat Knuckles the Echidna and the Chaotix joined by Mighty the Armadillo. Despite this, Eggman continued employing Metal Sonic as one of his top enforcers, though he did create later versions of Silver Sonic that appeared on the Egg Carrier and as a Badnik Horde Commander. (VG: StH2(8), SCD, StH2, KC, S&K, SA/SADX; StH: #253, #269; SSD: #12)
- The Archie Comics are the first branch of the series to give this group an actual name; they are usually known more simply as "Sonic robots."