BatsIf you stand around doing nothing for too long, bats come and attack you. They can be killed and were incentive to keep moving.
Cancelled conversionsST and Amiga conversions were planned by Ocean, and advertised as 'coming soon' at one point, but never released, apparently due to 'technical difficulties' (WEC Le Mans never reached those systems for the same reason). However, in 2014 a working disk with a demo of Rastan for the Atari ST was found. The demo is running, but far from finished.
Game Gear versionRastan was released for the Game Gear in Japan. However, unlike most other Game Gear games, it was a straight port of the Master System version, running not in a letterbox format, but instead using the GG's Master System compatibility mode, resulting in a fuzzy screen with small sprites which is difficult to render in screenshots.
Master System versionThe instruction manual for the Master System version of this game is notorious for containing several nude female enemies (Harpie, Meduza, Gorgon), which have bare breasts and what appears to be pubic hair.
Information also contributed by Игги Друге, Jo ST, Martin Smith, and Psionic