火吹山の魔法使い “The Warlock of Firetop Mountain” (1984) set off a gamebook boom in Japan which would last through the end of the 1980s. Shakaishisosha, originally a publisher of middlebrow science books, translated the first 33 titles in the Fighting Fantasy series. Fighting Fantasy gamebooks use character sheets and dice, so they can serve as a gateway drug if you will to role playing games. Shakaishisosha themselves would go on to publish several RPGs, mostly translations of stuff originally published in the UK.
Gamebooks in Japan were invariably published as bunkobons, which are the mass market paperbacks of Japan. A lot of RPG material would get published in bunkobon format too. Bunkonbons are A6 sized, which is about an inch shorter than an American mass market paperback. They have dust covers and are often sold with an obi. All the bunkobons I’ve seen are East Asian style books with the front cover on the right and vertical text.
To play “The Warlock of Firetop Mountain”, one must first generate a character by rolling d6+6 for SKILL, 2d6+12 for STAMINA, and d6+6 for LUCK. Monsters also have SKILL and STAMINA. When fighting, both the player and the monster roll 2d6 and add their SKILL. Whoever has the lower sum subtracts 2 from their STAMINA.
The Japanese version of “The Warlock of Firetop Mountain” uses the art from the original UK edition: the cover is by Peter Andrew Jones and the interior art by Russ Nicholson. The translator is Sayako Asaba.