"A Guide to Creatures of the Endless Frontier"
Paraphrased from the back of the book:
Over 300 creature for a GURPS Space or any science fiction roleplaying campaign. Creatures big and small, wild and domestic. From mundane or exotic environments.
Works for fantasy, horror or post-apocalypse games as well. Some of the more powerful creatures would work in a GURPS Supers campaign.
Advice for GMs as to how to create their own creatures.