From the Publisher:
The Wasteland Bestiary is a stand-alone OGL product to be used in conjunction with the Exodus d20 Survivor's Guide or Exodus OGL Survivor's Guide. The Bestiary details common animals and other wasteland terrors that survived the Exodus through adaptation, evolution, and mutation. A fully customizable creature build system (similar to the Custom Class) is built into the Bestiary along with a alternative EXPERIENCE combat system.
The Exodus Wasteland Bestiary is fully compatible with any Modern/Post Apocalyptic or 3.5 system books.
Creature Creation (custom creation, challenge rating creation, and the CEL experience system)
Wasteland Bestiary (over 80 detailed Wasteland Critters)
Bestiary Feats and Talents (list of Exodus feats and talents commonly used by critters of the wastes)