From publisher blurb:
In the gonzo world of the Last Sun, the time of the Great Disaster caused an enormous amount of ecological damage to the world. Not only did many humans die or mutate, countless horrific monster-races evolved to rule and threaten. Create creatures for your gonzo and weired-fantasy OSR games, from the anthropomorphic mammals and energy beings to lizardmen and tentaclebeings. Random tables guide you along the process and add special qualities, such as immunities, intangibility, explosive, radioactive, psionic, and multiple arms.