It was only in late-1990s that Toei Company incorporated the Space Sheriff and Rescue Police trilogies as subseries of the Metal Hero.
Some of the Metal Hero Series even spawned such sequels which followed the continuity of the previous shows, resulting in the genre developing sub-categories based mainly on space, military and police-related characters.
Zaido: Pulis Pangkalawakan was greenlighted by Toei as a sequel to Shaider, with characters who are descendants of those in the original series.
[1] Toei later halted production, instead authorizing a spin-off series set 20 years after the end of Shaider.
Machine Man and Bicrosser were created by Shotaro Ishinomori, while Changéríon's armor is not metallic and aired on TV Tokyo.
The game featured Gavan, Sharivan and Shaider all teaming up to battle past enemies from their series.