From the Back of the Book:
Animal and Machine...
New Predators of a Shattered World
For more than a century, people played with genes like toys and made computers think and dream. Now, new species of plants and animals fill the places humanity once ruled. Things that were once machines and tools now prey on the descendants of their makers.
This creature compendium for the re-envisioned Gamma World contains full descriptions of many new monsters suitable for any d20 game. Machines & Mutants has a dozens of new species, including rules for playing non-human characters, and guidelines for building new mutations, revived extinct species and unique challenges. It also includes descriptions of electronic "species" as both monsters and characters, and expands the rules for solving technological mysteries.
Requires the use of the d20 Modern Roleplaying Game or Dungeons & Dragons Player’s Handbook. V.3.5, published by WOC.