Complex sentence: The Shogun Warriors were the central characters of a line of toys licensed by Mattel Inc. during the late 1970s that consisted of a series of imported Japanese robots based on anime and tokusatsu shows featuring giant robots.
Split into simpler sentences: The Shogun Warriors were the central characters of a line of toys licensed by Mattel Inc. during the late 1970s. They were a series of imported Japanese robots based on several anime and tokusatsu shows featuring giant robots.