Footsteps that shake the earth. Bodies so massive they splinter ancient redwoods as they pass. Venom more deadly than a cobra's, scaly armor that can shrug off grenades and laughs at bullets,teeth and spines sharp enough to tear through a tank's armor or disembowel a mammoth in a single swipe.
Dinosaurs are every child's favorite monster for a reason: they are impressive in a way that few other monsters can ever hope to match. The dinosaurs in this book might share a name with the creatures in the Monster Manual, D20 Modern Core Rulebook or Menace Manual, but they are very different beasts. These dinosaurs are smarter, tougher and more vicious. In accordance with current paleontological theory, these dinosaurs are fast moving, agile saurians which marry the strength and endurance of reptiles with the craftiness and voraciousness of mammals. These dinosaurs are pack hunters and watchful parents, not slow witted, lumbering behemoths.
Dinosaurs are grouped by phenotype, organizing them into groups with similar physical traits, without regard to evolutionary relationships or place in the geological time line. This book's dinos have unique abilities with little basis in reality: chameleonic skin, acidic blood, henomenal regenerative abilities among others, all included to add variety to what would otherwise be a very consistent set of monster stat blocks. However, most of the abilities found among this books dinosaurs are similar to abilities displayed by living animals who fill similar ecological niches in the modern world; more fantastic abilities are simply 'scaled up' versions of real world animal abilities.
These monstrous behemoths are all members of the Animal type- a creature type I have new respect for after completing the project. As such, they can be inserted into almost any D20 campaign. There's no weird magic or especially unusual powers here to mess with your game's sense of reality, just teeth longer than your forearm. (Oh, by the way, since everything in this book is an Animal, if you're playing a Druid and you don't don't start wild shaping into every dino in this book, you're playing the wrong way!)