Challenge of the GoBots (also known as Mighty Machine Men) is an American animated series produced by Hanna-Barbera Productions, based on the Gobots toy-line released from Tonka. Most of the toys were imported from the Japanese toy line Machine Robo. The show was first broadcast in syndication on September 8, 1984. It was later rerun on the USA Cartoon Express. However, it was never seen on the Cartoon Network (like many of Hanna Barbera's material), and has yet to be shown on Boomerang. The show is similar in theme to Hasbro's more popular Transformers series. GoBots dealt with two opposing forces of transforming robots from the planet Gobotron (which should not be confused with Cybertron): the heroic Guardians and the evil Renegades. The Guardians were led by Leader-1 with others including Turbo and Scooter. The Renegades were led by Cy-Kill, with Crasher and Cop-Tur among their ranks. The characters rarely had guns, instead shooting energy blasts out of their fists. Unlike Transformers, GoBots had regular female characters. (Transformers didn't introduce female robot characters until its second season, and then only as recurring, not regular characters.) However, the females were built like the males (only Crasher receiving any distinguishable female features). The GoBots' origin as organic beings accounted for the presence of genders among the robots. The series generally focused on the "lead" three robots from each faction (Leader-1, Turbo and Scooter vs. Cy-Kill, Cop-Tur and Crasher), who were virtually ever-present, with other characters seeming to rotate in "guest-star" roles. Unlike in The Transformers, GoBots had no clear divide between the two factions. The characters (as well as the toys) had no identifying insignias or markings to indicate their allegiance, although it was clearly indicated on the packaging. Likewise, there was no commonality of design within each faction. The only “theme” to a side was that anything that turned into a “monstrous” looking robot or vehicle was a Renegade. Perhaps the most distinguishing trait dividing Guardians from Renegades was the way their voices sounded. The Guardians' voices had an echo, while the Renegades' voices were more computer-like. The show spun off a big screen movie "Gobots: battle of the rock lords", and three japan series called machine robo. The france dub of machine robo is called "revenge of the gobots" and is dubbed as a sequal to the american series.