Western North America, 66 million years ago
Amidst the tall Equisetum and Araucaria, a terrifying beast prowled its domain. Its multi-ton bulk carried by two powerful legs allowed it to move silently through the Cretaceous undergrowth. The animal's deep breathing was rhythmically in tune with its steps. The heat of the day was accompanied by the droning of insects and calls of birds, belying the nature of this hot, tropical world. Suddenly, the creature stopped in its tracks it's heavy breaths quieted. Peering through the thicket of cycads and palmettos the creature saw a vast floodplain sprawled out in front of it.
Out on said floodplain there were dinosaurs, hundreds of dinosaurs. A vast herd of Edmontosaurus grazed on the plentiful ferns and water plants, unaware that they were being watched by anything. The setting sun turned the sky a fiery, hazy orange, mixed with yellows and reds, but it also cast dark shadows wherever plantlife grew to block out the lowered rays of light. The extra camouflage added by darkness made this the perfect time to hunt.
The creature on this particular hunt was none other than the mighty Tyrannosaurus rex, her powerful jaws flexed in anticipation of delivering a bone-crushing, septic bite to an unsuspecting victim. She had to wait though, as she spotted the bull, massive, muscular and imposing. A male in his prime like this could easily dispatch a predator like herself if she wasn't careful.
But before the bull could find her hiding place, a distressed honk from one of his many females sent the whole her into a panic! The herd members switched from their quadrupedal stances to a bipedal one, desperately searching for the cause of an alarm call. The sight of the panicked individual running towards the center of the herd caused more discourse, and led to the whole herd fleeing. The culprits of the mass-panic were five smaller theropods, feathered and very fast they chased and corralled the herbivores, surrounding them from the rear, snapping and screeching to startle them.
Some would argue that these creatures were called Nanotyrannus, but the Tyrannosaurus knew them as her children. It was only now that she broke her cover, to follow the herd. She was slow though, and would have to rely on the youngsters to flush out any weak individuals. They snapped and prodded at any creature they approached. Seeking, not to attack, but to provoke. They were testing each individual for weaknesses, searching for an individual to single out and isolate from its fellows, so their mother could finish what they had started.
As the Nanotyrannus moved from straggler to straggler they came upon a cow, who was limping badly. Upon realising their current target was injured, the little theropods began their attack on the hadrosaur and started to steer her away from her herdmates. Soon their mother was closing in, jaws at the ready, prepared to deliver a brutal killing blow. The crunch of bone echoed across the forest followed by the cry of a dying animal.
As the sun continued to set the nighttime chorus of screeches and primeval howls rang out and the ancient forest fell into darkness, with the exception of a few bright spots emanating from atop tall artificial spires.
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Oregon, USA, Modern Day
Sixty six million years later and that world was long gone, replaced by one ruled by mammals, and one species in particular, that being humanity.
But, on the inky black surface of the Northern Pacific Ocean, gently rising and falling like the breathing of a great behemoth, a sticky, orange and slightly luminous substance, ready to set back the clock to that forgotten time.
Meanwhile, in a dark, high tech laboratory a computer display pinged a bright flashing alert. The sound of approaching footprints rang out through the lab, until a pair of sickle-taloned feet stood in front of the device. The owner of the talons tapped away at the device until a sound of confirmation. A wicked sounding, masculine chuckle burst forth from a feathered chest "Perfect…" the creature purred to himself contentedly, "Things are finally starting to get a little interesting around here!"