You are in the forested plains of North America, 75 million years ago.

The air in the Late Cretaceous was thick with the scent of pine and humid, damp earth. Hiding behind a dense fern thicket near a muddy riverbank, you watched the 30-foot "frightful lizard"—a Daspletosaurus—methodically scan the treeline.

It wasn't as massive as a T. rex, but in the close quarters of the woodland, its 3-ton bulk was terrifying. Its face was scarred, perhaps from a fight with a rival Daspletosaurus, and its eyes—narrow and intensely focused—turned slowly towards your location. It smelled something, maybe you, and paused. You could hear its breath, a deep, rattling hiss...