From the book's back:Aliens & Artifacts finally brings two important aspects of scifi gaming to the Spacemaster universe: Alien Beasts and Alien technology.A&A includes: 14 fully described alien sentient races Nearly a hundred alien beasts grouped into eleven different ecosystems Dozens of artifacts, ranging from time warping Entropy Neutralizers to deadly Singularity Seeds Detailed character creation rules for each new race Dozens of adventure suggestions and world descriptions Rolemaster's Claw Law supplement, which is used to quantify the inherent attacks of A&A's alien beasts - BoardGameGeek