They came in the dead of night, a silent invasion. Humanity had been looking into the depths of space for an eternity, but never had they imagined such a curse. And yet, here they were. Apokolypsians, as they become known. A biotech species. One that had evolved to feast on the electrochemical energy that terrestrial species used for life and movement.

The red energy beams emitted by the creatures acted as magnets which sucked the life force out of any being unfortunate enough to be exposed to it.

They entered the ecosystem the size of a small kitten, almost cute people would argue. Then they began to evolve, the perfect apex predators. Each encounter made them stronger, their physical form adapting with every kill. The once kitten-like creatures grew, hunting larger and stronger animals.

They absorbed the qualities that the earth creatures had evolved. The legs of a spider, strength of an ant, jagged teeth of sharks yet the mouth structure of a leech. They learnt to swim like dolphins, climb like bears and, horrifically, began to fly, like vultures, scanning for their unfortunate prey.

Humanity had watched, aghast, as animal and plant life, as they knew it, withered away in the face of these vile monsters. But they were never one to accept defeat, especially in the face of adversity. And so, humans evolved.

New weapons, new armour. Designed to counter the affects of the beasts and, the latest technology, to harvest the power and turn it onto the enemy, burning flesh and bone of monsters and humans alike till corpses littered the once lush, green lands.

It was never going to be enough. Apokolypsians were adapted to evolve within seconds, to adopt whichever trait they found beneficial. Humanity never stood a chance. And yet, they fought, retaliating against the creatures of the night.

Escape, they had soon realised, wasn’t an option. Humanity was not yet capable of inter stellar travel, and inspections of the enemy ships proved fatal to any who date enter. The vessels used by the creatures were also sentient beings, attacking any foreign creature without hesitation.

And so, here they were. The final platoon. Bravely facing an enemy from whom there was no escape, no mercy. They lifted their weapons for the last time, accepting their defeat, their demise, their extinction.

The creatures entered a planet full of life, but would leave a barren desert.