The story so far:
In a great wave of massive ships, they came to Earth to conquer and destroy. In just a great a wave with just as many ships, they left the planet and the small handful of survivors. They left their enemy’s technology, what meager amount still remained in the form of one solitary, small ship and perhaps a few devices insignificant in size and purpose. They left the humans who had for a little over three months fought amongst each other for survival and status. They left Earth, seemingly never to return.
Harbingers, those who had enough to speculate on, speculated that the Mongerers had found new prey, another world worthy of conquering or destroying. If sentience and technology existed, much would be stolen and then the world destroyed. If animalistic societies existed, they would land their great ships upon the surface and enslave all.
Their hands tied and busy in transporting the humans to the safety of a new world, Harbingers could do nothing to save the next world the Mongerers strove for. They did not begrudge the humans their safety. Whether the others who would fall to the Mongerers were greater or far more primitive, it mattered not to the Harbingers. To them, all were equal, all worthy of saving.
The Harbingers had made two mistakes in their efforts towards Earth. The first began many months before as they watched the Mongerers surround the blue marbled planet. They believed the Mongerers would see humanity as Harbingers saw humanity. They acted upon the belief that their enemy would find the Humans sentient enough to destroy. But the Mongerers had not. Their intentions had never been to annihilate Earth. The device left in their wake during their first departure was not the world ender that the Harbingers had so often sought to thwart. It was a device that monitored the humans; it had studied their anatomy and their social aspects. The Mongerers had great plans for the bipeds that ruled a world they also worked to destroy.
The second mistake the Harbingers had made, not counting their underestimation, or perhaps their overestimation of the humans they transported, would be far more devastating perhaps than their first. As the Mongerers left Earth behind, the Harbingers believed their enemies had finally finished with humanity. They were wrong.