Humans feared very little. They fished and netted the largest fishes in the ocean, shot the most vicious of animals and took their hide as trophies. They burned down and razed the most verdant of forests, dammed and redirected the widest raging rivers, flattened and demolished the tallest of mountains to make way for their farms, factories, roads, and their tall, tall cities adorned with glimmering and shimmering skyscrapers.
Humans ruled. They oversaw countless millions of livestock who lived out their lives for the sole purpose of supplying their skin, flesh and unborn children for their consumption. They defiled the clear, flowing waters of the Earth with toxic chemicals and putrid waste, and covered the Earth's proud land with mountains of filthy trash. They and their ilk choked the fair Sky's shimmering aquamarine complexion with dark, caustic clouds of smog and smoke. Humans, as the crowned apex predator of their planet, ruled cruelly and viciously and knew exploitation to no bounds.
Yet, even the apex predator knows its position is not eternal, knows that it is not forever untouchable. Organisms develop. Species evolve. The food chain changes, and the king is dethroned. And thus, there was one thing they feared. An even higher predator.
And so, humans peered upwards in big telescopes and turned their widened eyes to the stars. They fretted and worried their hands over tall tales of their own origin. Of asteroids and comets which would never make impact and bring impossible fiery doom, of starships that did not exist to ferry the aliens that never would touch down on the surface of their planet, to unleash the nonexistent vengeance upon their world.
They should have known better. They should have known of the ancient terrors that lay, dormant in the dim, cavernous bowels of Mother Earth herself.
They should have known better than to dig too deep. Oh, woe to the unknowing humans who dared to intrude deeper and deeper, who bored down into the crust of the earth! Thus, when the humans disturbed the millions of dormant Parasites long—forgotten and sleeping in the darkest caves under Mother Earth's surface, the true apex predators of the Earth finally swarmed to the surface.
The first wave came as merely the messengers, merely the scouts, and the heralds. Hundreds of millions of tiny wormlike Buglins that burrowed into and ate and drove their victims to vicious insanity, of fast scuttling spiderlike Rupters which injected and turned their victims into walking, inhumane death. They enslaved and killed and consumed millions upon millions. They did not discriminate between human and animal, parent and child, or men and women.
The fine black asphalt streets and walkways became jammed with hungry Parasites. The towering skyscrapers became filled with corpses, enslaved humans and their controllers feeding on their kin. In a matter of weeks, civilization ground to a halt. And thus, the once—glittering human cities became a deathtrap of their own making in what they called it the Apocalypse, the Second Coming, the End of Life as They Knew It.