Sega Master System / Mark III / Game Gear
This is a talk page for discussion of The Black Onyx (ザ・ブラック オニキス). It may contain clarification on some of the details of the game, and is a good place to write if you think something is odd (and you have permission to edit the page...).
Note that this is not Wikipedia! Please make the discussion useful and readable.
In the Sega Masterpiece Album Phantasy Star article, Rieko Kodama mentioned working on art for this game, suggesting it was at least partially developed in-house.