By /u/LerrisHarrington on /r/HFY

The Humans died a long time ago. Well most of them anyway. Rumored sightings happen just often enough to keep people convinced they aren’t all gone. They didn’t destroy themselves like so many predicted, actually they went out in a manner that would be extremely satisfying to most of them. See the Humans had the most misunderstood reputation in the Galaxy. Average or below average in every way. Not strong, not smart, not quick, not very tough. Well they were pretty tough for a species without an exoskeleton.

Well liked though. Humans were friendly. Extremely tolerant. Big Human cities had just as many aliens as they did Humans, and nobody seemed to care. Generous, kind, selfless even. The poorest of them would give up what little they had to help strangers. If you were in trouble Humans would help you with little thought to their own safety. There were Humans who would kill themselves to save someone else. They found satisfaction thwarting Death. Death would happen on their terms, not His.

Oh yes, Death was a person to them. Not a thing, or an inevitability. He was a individual, to be fought, thwarted, cheated, escaped from, or even defeated if they could.

Which brings us to the one thing Humans were better at than anyone else, and how they choose to go out. Humans don’t take no for an answer. Humans look at impossible as a challenge. Tell the Humans there’s a region of space nobody’s ever returned from and they’ll ask for directions. Tell them the Laws of Physics forbid it and they’ll learn how to cheat them. Humans never stopped.

So when they were told about The Swarm, they didn’t do what everybody else did.

Just like every other species, shortly after first contact they were told about The Swarm. The Humans didn’t believe us at first. Turns out they’d already thought of a word for the problem and thought we were playing a prank on them. Grey Goo they called it. I see some confusion, it was a long time ago they barely teach it anymore. The Humans solved the problem so its ancient history now, they died solving it, you’d think that’d get them a place in the history books but everything gets forgotten eventually.

Grey Goo. A silly name for a terrifying problem. We have some AI students here right? Here’s why nothing you make can have self replication powers without user input. Some time, a very long time ago, even longer ago than the Humans, a species built some nanotech with self replicating powers. We know nothing about them, all that’s left was their nanotech, presumably it wiped them out. We don’t know what it was supposed to do but we know what it did.

Every few thousand years it’d sweep through the Galaxy, and scour every planet of any artificial structure. Our solution? We moved to orbital habitats, moved all our heavy industry into orbit. Then rebuilt, until the next cycle. The thing about AI is that it follows rules, so for whatever reason The Swarm never attacked anything in space, unless it attacked them first. It would come in, ignore billions in orbit, do its assigned task and leave.

The Humans? They didn’t move into orbit. To them running wasn’t a solution. The Swarm was a problem and they’d solve it.

They did exactly what others have done before. They armed for war.

At first everyone tried to talk them out of it, we’d seen so many others try and fail only to be wiped out. After it became clear they wouldn’t change their mind, we treated them differently. They were a dead species, nobody had ever fought off The Swarm, so why make friends with a dead man. It didn’t take too much time after that before attitudes slowly started changing.

A couple of years after that though, attitudes changed from cold and distant to curious, and then impressed. The Humans armed for war on a scale nobody thought possible. They took technology and ideas and built them out to scales no one had dreamed of. We shield ships and bases, they shielded planets and then when satisfied they’d figured that out, their entire solar system. Not once, not a few times, not tens or even hundreds. They layered thousands of shields over their entire solar system. They build a fleet so massive they ran out of soldiers to put on it, so then they built drones. Countless drones. They didn’t just arm themselves, they armed their entire solar system. Anything large enough had weapons and shields mounted to it, anything too small was broken down for material. Any spare space that didn’t have a weapon emplacement had a station built to cover it. Every inch of their system was armed.

The Humans had a plan, they could get their shields so large because they weren’t combat shields. Nanotech is dangerous because of its scale, the Human’s shields were designed to create an environment that would force the nanotech to assemble itself into a larger structure, something capable of countering the fields, but in turn more vulnerable to attack.

People started to believe they might win after all. It had been a long time since the last appearance of The Swarm.

Then the Human scouts returned. They’d found The Swarm, it was closer than anyone had expected though. Everyone forgot about the Humans as they started their own evacuation efforts. We didn’t think of them again till much later. We had expected the Swarm in a month. A month came and went, then another, then another. No one wanted to risk moving back down to their planets, not when no one knew where The Swarm was. So we sent scouts to the Human system.

They were still fighting. They were fighting well enough that The Swarm had changed behaviors. It’d never done that before. We always thought it had to have some FTL communications ability, but could never be sure, till now. All the parts of The Swarm that should have been sweeping our systems were there, with the Humans. The Humans had fought for four months and held their fortress, forcing The Swarm to call in more and more reinforcements.

Disbelief gave way and reality seeped in. The Humans had not entirely had their own way. Their system was missing half its planets. And as we watched they detonated a fifth rather than let The Swarm consume it.

We sent for our fleets, for all the good they would do. We had not armed as the Humans had, what few ships that would arrive in time would be as a breeze before the hurricane.

So we watched, as the Humans fought a nightmare. They made that nightmare pay, more for each precious kilometer than any would have thought possible. The humans were good at impossible. Even a victory for The Swarm was a loss. They detonated planet after planet as The Swarm overwhelmed each, but even such titanic acts of destruction could not save them. They were soon fighting in the orbit of their home planet, and then that too was lost.

Rather than lose heart, this only enraged them, the humans fought back harder, new more powerful weapons came online, engines of destruction powered by their star, the humans had been holding back their most terrible weapons for fear of damage to their home. They no longer held such a concern.

But through it all The Swarm kept coming.

The Humans were pushed back again, detonated another planet again, buying themselves a brief advantage again, were pushed back again. But before detonating their final planet they noticed something. The Swarm had stopped coming. The unending flow of reinforcements had ceased.

They still couldn’t possibly win, their system was overrun. It was beyond overrun. Far too much remained for what little the humans had left. But this news seemed to please the Humans. They ordered all those watching to flee. Said they had one last weapon to use, and staying would be dangerous. So we left. We dropped probes to watch and we left, not knowing what they planned or what they could possibly have had in reserve.

As soon as we exited the system we learned, the Humans did indeed have one last weapon at their disposal and it dwarfed anything they’d used before then. The Humans detonated their Star. They went out on their terms. Even as they lost everything, they got what they wanted. They saved everybody else, by destroying the last of The Swarm.

Humans are good at Impossible.

So, do I think they might still be out there? Well, I wouldn’t say it was impossible.