First released in Japan as 'Ganseki Chōjin' (Rock Supermen) as an extension of the Machine Robo Series range they were quickly added to the US Gobots, EU Robo Machine and AU Machine Men lines.
Regardless of untraditional alternative modes, they sold well enough to prop up the flagging Tonka Gobots. With Western markets demanding more 600 Scale Gobots figures and Bandai no longer supplying new models to Tonka the Rock Lords were a timely addition.
Production figure colour variants are limited to the Japanese versions vs. the all other releases while some series one weapons saw locale based colour variations. Slimestone and Pulver-Eyes were released in Japan originally aligned to different factions than their later Western releases.
In Japan Machine Robo Series Ganseki Chōjin were issued in colourful, cardboard boxes with foam inserts and plastic viewing windows. The US and UK figures sold as Tonka Gobots on traditional cardbacks in blister bubbles while in Europe they came as Bandai Gobots, 'A Robo Machine Product' in impressive sized cardboard boxes with large, plastic viewing windows. A parallel release in Australia as part of the Bandai Machine Men line saw them packed in the same boxes as in Europe but with no mention of Gobots
The first release Rock Lords figures were listed as 'Heroic' or 'Evil', then when re-release along with the second series heroic was changed to 'Good'.
1986 - 1987 Bandai - Machine Robo Series - Japan
1986 - 1987 Bandai - Gobots 'A Robo Machine Product' - Europe
1986 - 1986 Bandai - Machine Men - Australia
1986 - 1987 Tonka - Gobots - United States / Canada / United Kingdom