Machine Robo: Revenge of Cronos (マシンロボ クロノスの大逆襲, Machine Robo: Chronos no Dai Gyakushū?) is a Japanese anime television series produced by Ashi Productions. It ran on TV Tokyo from July 3, 1986 through May 28, 1987.
A large portion of the Machine Robo toy-line was exported and sold by Tonka in America as GoBots and Rock Lords. To date, only 15 episodes of the series have officially been released with English subtitles on three DVDs by Central Park Media.
The story takes place on the mechanical world of Cronos. A band of villains called the Gyandlar have come to the planet in search of the mythical energy know as the Hyribead.
When Revenge of Cronos left off, Rom and Leina had crossed a dimensional barrier. Their physical forms changed from robot to human and they were separated with blurred memories. Leina Stol is incarnated as Reina Haruka, a Japanese schoolgirl. As the story progresses, she meets up with Rod Drill, Blue Jet, Triple Jim, and Rom; all of whom are now human.
Taking place in the middle of the Wolf Sword Legend feature, this story centers on Leina Haruka, whose plane has been hijacked by a group of thugs led by the supernatural wizard Zarik. At this point, the series has no resemblance whatsoever to the Machine Robo toyline that spawned it.