You are in the forested floodplains of South America, 215 million years ago.

The air in the Late Triassic was thick, hot, and smelled of dry earth and sulfur. You pressed yourself deeper into the thicket of ferns, watching the riverbank. Through the dusty haze, you saw a Zupaysaurus emerging from the red sandstones.

It was roughly thirteen feet long, walking easily on its hind legs, a bipedal nightmare with a long, elegant neck. The most terrifying detail was its head—the snout was long and narrow, but riding on top were two parallel, bony crests that ran from its nose back toward its eyes. It wasn't a giant like the later T. rex, but it was fast, nimble, and clearly the master of this domain.

The predator paused, its kinked jaw turning slowly. You held your breath as a low, guttural hissing noise echoed from its throat—far more bird-like and unsettling than the monstrous roars of hollywood. The creature snapped its head toward your thicket, its dark eyes locking onto the movement…