Alien Syndrome, a 1991 release for the Sega Master System, shares gameplay mechanics and aesthetics with other action titles on the platform. The game puts players in a science fiction setting, typically fighting aliens in side-scrolling levels. This version, released in the USA and Europe, represents a standard version with minimal regional changes (if any), common in many Master System releases of the era.  Sega developed and published this title.

Alien Syndrome (USA, Europe)

Alien 3 (Europe)