You are in the forests of Australia, 120 million years ago.
The air was humid, thick with the scent of wet ferns and ancient pine. You crouched by the cycads, watching the muddy banks of a slow-moving river.
Something was moving through the low undergrowth. A small, heavily armored creature, barely three meters long, emerged from the ferns. It was a Minmi. It looked like a lion-sized, leathery tank, with rows of bony scutes running from its small, beak-like head down to its stiff tail. It didn't have the massive tail club of its later cousins, but its skin was studded with small, protective spikes, and you could see the odd, bony plates along its flanks that helped it move surprisingly fast for a "living rock."
It ignored you, busy nipping at soft plant matter with its beak.