A sourcebook and campaign setting covering everything you need to adventure on the world of Cretasus. Features: History and background of the Main Valley and its settled regions, including New Savannah, Fort Tecumseh, Plesiosaur Bay, and other major areas. More information on the mysterious dinosaurs of Cretasus: their habits, behaviors, and interaction with each other and humans. Prestige classes for Dino Warriors and Federal Marshals. GM source material, adventure ideas, town generation guidelines, treasure and encounter tables, and more. d20 stats for 22 more dinosaurs and other prehistoric creatures, including seven marine monsters, plus the alien Scray. d20 rules for vehicles and the Union's ironclads. The Cretasus Adventure Guide is the second book in the Broncosaurus Rex series. It requires the use of the Broncosaurus Rex Core Rulebook.