Transformers: Zone was the name of Takara’s 1990 segment of G1. Following the waning success of Victory, Zone was much smaller, including only two Decepticon sets. The entire series focused entirely on Micro Transformers (known as Micromasters in the US), and larger robots that interacted directly with the Micro Transformers.
Following the massive divergence of Victory (and in a way, Masterforce before that) from Hasbro product, Zone returned to scoop up many of the Hasbro selections from the previous year. This may have been in part because declining sales limited the impetus to developing a large number of new toys for the Japanese market. At the same time, Hasbro’s line was on its deathbed, and the new figures released in their markets required little engineering (the Action Masters). As such, Zone included nearly all of the 1989 Micromasters products, (albeit with some redecos), and several of the 1990 Hasbro releases. Zone also included a handful of indigenous designs, primarily the Powered Masters. These electric or spring motorized large figures could transform into various bases for the Micro Transformers, as well as combining into a large vehicle mode.
Supported only by one 30-minute OVA and a comic strip in TV Magazine, Zone did not enjoy wide distribution compared to previous series, but unlike the US market, Japan’s desire for more transformers was not yet completely tapped out, and the line would continue with Return of Convoy.