We all knew it was going to happen; we just didn't know when.

At first they called us paranoid, conspiracy theorists, crackpots, and more. Who would believe in demons in this day and age? Just because we found some ancient tablets detailing a prophecy? Even with the bones of creatures distinctly unlike people?

It wasn't until the first portals opened that the world took us seriously. Our little research office, formerly only visited by tabloid journalists, suddenly became the attention of every TV station, government agency, and military representative. The demons had been fought back with the military's full might, but only because it was a scouting force. They had tested us, and they would be back. Money, personnel, and resources would be no object, so long as we could deliver results based on our research. We went from one tiny office to a nationwide agency in a matter of days.

Yet those ancient civilizations we dug up the remains of had something we did not: magic. Such arts passed from the world long ago, leaving us without the weapon they used against those demons millennia prior. Instead we must use what the ancient peoples did not have, and put our technology to the test. Those who deciphered the ancient tablets believe that the magic used by our predecessors created a noise beyond the hearing range of mortals like us, but we do not know what it did. We can analyze it scientifically, of course – it's an ultra-low-frequency sound wave with many layers to its composition. But what does it do? We wouldn't know until the field test, and that requires test subjects.

The opportunity came when the seismograph at the field outpost I was working at went wild, picking up distant tremors that only grew in strength until we could feel them for ourselves. There were no fault lines nearby, no volcanoes, nothing that could cause it – except a herald of the demonic invasion. And this time it was more than a mere scouting party. Quick calls to our other outposts triangulated where the waves were coming from, and pinpointed the location where the demons were arriving. The army was on its way, but the best they could do was buy time; success or failure would rest on our shoulders alone.

The untested prototype was hauled into the back of our research van, secured to the rack next to the generator, and I remained in the back to hook our machine up to the sound projector welded to the roof while my colleagues drove us with reckless abandon to the arrival site. Flanked by an escort of numerous military vehicles, we sped down the highway in the opposite direction to where all the other cars were going. The prototype was a big, boxy machine, favoring practicality over style in every facet of its design, with exposed wires and the big capacitor at the back duct-taped onto the housing. This ramshackle device was our only hope, so it was with great care that I and the other researcher in the back of the van prepared it for its inaugural run.

Along the way we were joined by several helicopters as an escort, yet we knew that such a force would be little more than a momentary annoyance to the full might of the demon army once they arrived. The sky ahead of us gradually changed from its normal blue to a deep crimson the color of blood, the clouds turning an ashen gray. The rumbling of the ground under us became all the more noticeable as we got closer to the arrival site, still a few miles away, until a great explosion in the distance sent a cloud of ash into the air.

Flaming rocks rained from the skies around us, forcing our convoy to swerve around them when they landed on the highway, setting trees and fields around us alight. One of our military escorts lost control and went off-road, their armored vehicle flipping over, but we had no time to go back for them; every moment was of the essence.

The demons were opening their portal in a wide yet not terribly steep valley cut by a river; if they succeeded they would be able to spread in all directions and we would have no hope of containing them. Already it seemed like we might be too late, for when we arrived there was an enormous jagged hole torn in the ground, flaming embers rising from it into the air as multitudes of demons crawled out. Their bodies were jet black and spiky, covered in some sort of chitinous growth, often with horns in a wide variety of shapes, some curled and others straight. All of them had tails, some had wings, and a few wielded black steel weapons instead of relying merely on their claws and fangs. Even the smallest among them stood a foot taller than the average person, while the stronger ones towered over them, at least three to four meters in height.

They clearly intended to make this a permanent opening, as most of the demons emerging from the burning gouge in the land were wresting barricades and structures from the ground with their magic, forming twisted black walls that stopped the bullets being fired their way from the soldiers nearby. Others were working on enlarging the portal, their gestures leaving burning reddish-purple runes in the air from some demonic script that hurt my eyes simply to look at. The portal had cut through the river in the valley, leaving it dry on the southernmost end as water poured into the chasm at the north, clouds of steam rising as it flowed over the burning rocky sides.

We separated from our escorts; they would do their best to distract the demons and keep their attention away from us. We slowed down to turn off-road, leaving a trail of flattened grasses behind us as we got as close as we dared to do so, staying at the top of the valley without venturing into it.

"It's not ready!" I called frantically as I continued to hook up cables; doing so in a moving and frequently-swerving vehicle was difficult, but now that we had come to a stop – even if the ground was still shaking – I could work much faster. "I need a few more moments!"

"Hurry it up!" my colleague called from the driver's seat. "I don't know how long we'll stay unnoticed!"

Just as I was about to plug in the final connector, a much greater trembling of the ground forced me to brace myself and hold the machine steady. The portal the demons had opened was widening again, much more than before – and this time it was no mere minion that emerged from the portal, as a great black hand the size of a house rose up from the portal and reached skyward before grabbing onto the ground, demons scattering to get out of the way. A second and equally large hand came forth from the portal and grabbed the ground on the opposite side, enormous claws that could have sheared an aircraft carrier in two digging into the soil.

With a thunderous crack it pushed on the sides of the portal and tore it open, sending clods of dirt flying into the air while raising mounds of rock to either side. It was all I could do to even remain on my feet as the ground shook beneath us, the van's shock absorbers sorely outmatched by the power of the tremors. Even with my greatly restricted sight line from within the van, looking out past the front seats, it was impossible to miss the sheer enormity of the creature pulling itself free of the ground.

It bore a notable resemblance to the rest of the demons: jet black and covered with some bony or chitinous substance that served as a layer of armor, and with many, many spikes over its body. Curled spikes on its shoulders, long straight spikes at its elbows and knees, spines down its back and tail... there were few places without any sort of spikes, even a large one between its legs. Its face was the only thing not ebony colored, in the shape of an animal-like skull, complete with bony curled horns, and only two glowing, burning white flames in the eye sockets rather than actual eyes. But above all else the thing was truly titanic, tall enough to rival a skyscraper, and when it pulled itself fully free from the rift and set its feet down on the ground, the impact of them alone was enough to make the ground shake again and snap me out of the stunned terror its visage had placed me in.

Jamming the final connector into the prototype, I began flicking switches, moving dials and pushing levers to turn it on and get it calibrated. I had to hope the generator would hold out for long enough. A glance out the front window told me that things were going as poorly as I expected: though the military was assaulting the gigantic demon with everything it had, all of the bullets seemed to simply bounce off, the explosive shells from tanks leaving not even a scratch, rockets from the helicopters detonating harmlessly on the monster's surface. All while the demons milling around at its feet continued to fortify themselves, raising more hellish barricades from the burned ground.

Leaving one of my colleagues in the back to handle the machine, I snatched up a pair of binoculars on my way out, jumping out from the back of the van before climbing up the ladder on the side to the roof. The sound projector looked almost like a satellite dish to the untrained eye, albeit one missing the antenna in the middle. Rather, it would amplify and focus the sound wave so that it would go in the direction we were aiming, rather than spreading out away from the demons uselessly. We were still a long distance away from them, but I dared not order my associates to drive closer – if they would even listen to such a command.

With the controls attached to the frame holding up the projector, I took aim directly at the towering demon that seemed to be amused by the military's feeble attempts to harm it. It would have to be dealt with, or it didn't matter how many of the lesser demons we felled, if that was even what this machine would do. Shouting to my associate down below to activate the prototype, I saw lights on the back of the projector turn on as the signal began to come through, and as my heart raced, I threw the switch to bring the projector array to full power, then leaned to the side to observe the results, holding up the binoculars to watch.

There was no visible or audible effect – it was, after all, a low-frequency sound, and the only indication I had that it was working was the meters and gauges on the back of the projector indicating it was receiving power and a signal. It took a half-second for the sound wave to reach the demons, yet the effects when it did were too obvious to possibly miss.

Firstly, the demons froze in place the moment the sound reached them, but for those that were flying, who abruptly dropped to land on the ground. Then they cowered, seeking cover behind the barricades they had put up, or simply crouching low on the spot. The largest demon's head turned to face us, and my heart skipped a beat when it did; now that we had caught its attention, we were surely doomed. Yet in those burning white eyes and in the way it recoiled, with its mouth slightly open, I saw only one emotion: fear.

The demons on the ground continued to cower, or so I thought: with a glance downwards through the binoculars I could see it was actually something else entirely. Some had crouched down and many had their hands between their legs, trembling in place, in a manner reminiscent of someone desperately waiting for a bathroom to open up. That analogy turned out to be rather apt, as though it was difficult to make out at a distance even with my binoculars, I could just about see the flow of liquid onto the ground from the lesser demons. That spike between the legs of most of them was clearly some sort of phallus, for the fluid gushing from them sprayed from the tip of it. And for those without the spike, presumably female demons, while several of them had bent their legs, a few remained standing, streams of golden liquid gushing forth from between their legs and onto the ground below them.

It was not the effect I had expected, but it certainly seemed to have thrown them into complete disarray nonetheless. "It's working!" I shouted triumphantly, lifting my gaze upwards to the gigantic demon, who seemed to be better resisting the effects of the sound being projected at it. It opened its mouth, yet I heard nothing; if it was making any sound, it too was beyond my hearing. The lesser minions seemed to be turning their gazes up to their leader, perhaps expecting it to rally them, yet for the moment it was standing in place, visibly struggling to resist the effects of the sound projector.

"Keep it going!" I yelled out as I saw many of the smaller demons turning and fleeing back towards the portal with another quick look down to the ground. I was excited, yet also terrified; for all I knew at any moment their leader could break free from its fear and come crush us with one swing of its fist or a stomp of its foot. Then its legs began to tremble, and cross, and recalling what I had seen of the lesser demons, I realized that for the leader as well, that spike between its legs was actually a demonic penis...

That fact became clear the moment a dark yellow fluid began to cascade from the tip, and though the demon quickly brought his hands between his legs in an attempt to stop the flow, it continued unabated, with many separate waterfalls of demon urine now spilling from its hands in different places. He was literally pissing himself in fear, as were his underlings... yet his own titanic size, previously an advantage we had no chance of surmounting, was now working against him. The wave of his piss, even split up into separate flows by its hands, had the volume of a raging waterfall, and was falling from a great enough height to carry an immense amount of force with it.

When the urine struck the ground, it both gouged holes into the dirt and grass, while also pouring outwards in a veritable tidal wave. The demons on the ground, including the winged ones that had stopped flying, were caught up in it and washed away, many of them swept right back into the jagged portal they had emerged from in the first place. The massive demon gave a growl of frustration that was audible to us, taking a step back from the projector without looking where he was going and crushing many of the demonic barricades under his feet as he did. His torrential flow of urine continued to pour forth, scattering demons about if they weren't simply washed back into the portal, and even the ones that weren't continued to retreat into it and out of sight.

He looked downwards at the sight of his own army fleeing or helplessly being washed away by the deluge of his own piss, and then he turned to us again, his gaze both fearful and hateful. My triumphant feeling began to fade; surely he would eventually run out and then come after us, and even without his minions we were no match for him. Yet instead, he bellowed loudly, forming words certainly not in my native language, yet understandable somehow even if the profane mouth they came from made my ears hurt just to listen. "MORTALS, KNOW THIS," he roared, "WE SHALL RETURN AGAIN, AND WE SHALL END YOU ONCE AND FOR ALL!"

After swearing his vengeance on us, he turned to the portal, the last of his minions either leaping into it or falling into it with the innumerable gallons of dark yellow demon urine. Despite his words, he leapt into the portal as if desperate to escape, sending a final spray of his piss splashing all over the valley on the way down. Upon disappearing back to wherever he came from, the glowing of the portal ceased and the embers stopped rising from it, the jagged hole in the land pulling itself closed. The remnants of the twisted walls the demons had put up remained, as did the veritable lake of piss he had left behind which was now flowing down the river channel, and the fires his army had started were still burning... but somehow, we had won.

The manner of our victory brought new meaning to the term 'humiliating defeat', but it was still a victory. Now it would be our turn to leave records for our descendants to find...
