The second, third, and fourth salvos came and went. Two types of projectiles fired at staggered intervals.

  When one cluster of electrics entered its cooling phase, another would pick up the slack. As one unit exchanged out its spent focusing crystal, another finished the process.

  The sonic emplacements had to retreat through hatches to replace empty ammunition belts. The same staggered firing scheme happened elsewhere on the Titan. New clusters traded out with old ones on second-based intervals. Most of the brutalized Aud had no idea what was hitting them, but more fell. More were falling still.

  Re-5's tongue kissed the spot where she'd bitten her cheek. The stinging didn't distract her except for when it flared.

  When the map updated, she realized the south had solidified its threat. The prior isolated movement clusters joined together, covering good ground in their climb. So much so fast was noteworthy, but a frenzy could explain it.

  Aud usually entered one when they heard emplacement fire. Good news was that they still had time. No matter how fast the Aud charged up the rocky walls, they were still fighting gravity. Gravity didn't take challenges to its authority sitting down.

  The Titan's crew would appreciate the delay, since they had another pressing concern. They'd gotten a visual on the northern horde.

  "Did we detect blue or purple fur?"

  Qa-3 pilfered a microchip from somewhere and handed it to her. Plugging it into her HUD brought up a diagram of the tunnel. This one was different from the map on the overhead screens. Some details about the physical structure were off, but that'd be normal.

  Scans looking for high-tier Aud did weird things. Something about how the scanners implemented them distorted data on the environment. She didn't understand the principles behind them any more specific than that.

  As for the scan results, a wide sprawl of color occupied the north side. Blank spaces peppered the eye-watering blanket. That was because the horde funneled through several inverted stalactites. Rock had formed up from the ground in thick semi-pillars like trident points.

  Most of the color was white. White, orange, and yellow. That'd be the standard disposition of every group of Aud, barring exceptions.

  She saw small pinpricks of green breaking through. They seemed brighter. Maybe it reflected a green's increased strength compared to the lower tiers? They looked obvious even among the ocean of white, lakes of orange, and strings of yellow.

  Her eyes raked through the image, searching for the inevitable, but failing. Her lungs unpetrified. The northern horde had nothing stronger than green. She clapped Qa-3's shoulder, shuddering and allowing herself a lip quirk. " Continue with the diversion of firepower as planned. But lower the distribution from a third to a fourth."

  He raised an eyebrow, then took the microchip back to check the fur scan himself. Re-5's cheeks colored. Come on. Even if he distrusted her analysis of the situation, did he need to make it so obvious?

  A small sliver of doubt had her waiting for him to say there was what she hadn't seen. That where she'd seen a void for blue or purple, he'd see the colors themselves. His brow scrunched up, and he nodded at her while pulling out the microchip.

  Good to know she wasn't so worried she was making mistakes already. She turned back to the console and adjusted the emplacements' recommended firing rate.

  "Can you start running unlikely combat scenarios?" she asked her HUD. "We're not going to mess up for a couple of minutes now that we've established our position. It'll afford us a small safety blanket."

  "An assumed one," Qa-3 said behind her. "Let's not lower our guards already, sir."

  She waved him off while her HUD processed her request. The superhorde was still their priority. So long as no surprises came from the south, they could pummel the falling Aud with impunity.

  "Notice: Confirmation: Will raise notice when likelihood of uncommon event has calculated probability above fifty percent."

  She flinched as new warning klaxons blared. The earliest markers connected with the flat ground and lay still. Then the number of impacts moved from single digits to double. A few more heartbeats, it reached triple, and there were no signs of slowing down.

  She checked Qa-3 out of the corner of her eye. He was looking down at a handheld, his fingers clenching the edge.

  Most of the bodies were exactly that--bodies. Every last one had crashed into a thick rock layer from who knew how high up. That was after the Titan had blasted them with the electric and sonic hail. Repeated shots had weakened most of the Aud, and hitting the ground at the end seemed to seal the deal.

  But if a fall was all it took, humanity would've never found itself on the brink. Dispersed pockets of survivors reared their heads among the dead. The enemy was back in control.

  They growled, obscured by the thuds around them and the roaring emplacements. When no challenge noise came, the volume rose until blood-curdling screams rang out. Echoes formed up fast, coming from the endpoints of the greater tunnel.

  Some of the survivors joined into larger clumps, others separated and broke apart. Now that they were on the ground, their target had shifted.

  Right on cue, a wall of emplacements redirected their sightlines to face the stragglers. Electrics whirred while saturating the focusing crystals. Sonics chambered fresh rounds. The beams hit first, biting into fur and charring. Sonic rounds smacked into the marked targets, pulverizing rock and Aud flesh alike.

  The atmosphere looked to be on the rise. The crew was bleeding them. Killing them, eventually. Did some of them see it as paying the Aud back for every life taken?

  She didn't. Each Aud casualty was a single digit in a statistic. They didn't have names, ambitions, families, or belonging. All they had was a mindless lust for violence and human extermination.

  She wouldn't insult all the human casualties of this war by considering a single Aud death equal to a human's. One human needed lots more for reclamation. It wouldn't matter, even if she happened to agree. Three centuries' worth of massacres was too much to recoup in a single skirmish.

  Aiming the emplacements was going smoother, thanks to the targeting programs. The autonomous intelligences had helped them along by drawing upon a massive database of Aud recordings.

  They could analyze details down to the smallest of movements. Trial-and-error tests ran in tandem. More Aud turned black, more knocked away like pebbles before a giant's thumb.

  It still wasn't enough. For every one Aud killed in the air, three more made it to the ground. For every Aud that died on impact, two more survived. For every one gunned down before crossing a kilometer, there was another to take its place.

  So many corpses in a single place pleased all the humans aboard the Titan. They'd have to be emotionless not to feel something. But the evident lack of progress gnawed on her thoughts, dulling the sense of achievement.

  The northern horde was close to entering their line of fire. The southern horde wasn't far behind. Despite pressuring the superhorde with everything they had, they were the ones on the back foot. How deadly a foe were the Aud, that their presence and numbers were enough to do that?

  That was a question for philosophers to ask, hiding behind walls far away. Others seemed more prudent to ask right now in the command compartment. Such as...

  "My threat wasn't clear enough, or everyone in the echo room has balls of scutumsteel. Either way, I will throw someone from the scanning crew out if I don't get a check-in on that intensive scan. Could you get to that?"

  The last stalactites on the edge of the formation were thinner compared to those in the center. The northern horde crashed right through them. White and orange breached the arena in a flood of jagged stone, kicked-up dust, and catapulted fur.

  One wave spilled out, and more behind that one formed a more terrible second wave to crush it. Like all things about the Aud, it forced Re-5 to maintain a rigid posture, else her legs would start shaking.

  Survivors from the superhorde called out to their brethren coming from the north. The appearance of new kin emboldened them with renewed vigor. Injuries seemed less lethal than before--or the Aud were less willing to succumb to them. The still falling members of the superhorde echoed the screeches even as the rounds and beams claimed more of them.

  If she wanted to describe their predicament, strained would work, but dire felt more appropriate. A quarter of the turrets broke sustained fire to twist in their sockets. New targets from the northern horde lit up for the targeting programs. Necessity forced the gunnery crew's hand as the pincer move enveloped the Titan.

  Re-5 didn't think for a second they could kill the accumulated superhorde. This wasn't even the entire amount! The southern stragglers hadn't finished their climb yet and would join up at some point.

  Few of her officers thought the situation wouldn't become hopeless the second an Aud got close enough to bite or scratch the exterior. That applied to anything, from the sealed breach to the most insignificant surface module.

  Because the Aud worked that way. Cut down one, and there would be another. Rinse. Repeat. This basic mantra didn't account for how many injuries each tier could withstand. But they cut down plenty, and no one in the command compartment could deny that.

  Rounds and beams lanced through hundreds of hole-ridden, charred bodies each second. Child's play to the Aud. The Nyx Breaker needed more than a thousand emplacements. They needed ten times that at least to decimate the superhorde.

  If you come across this story on Amazon, be aware that it has been stolen from Royal Road. Please report it.

  As things stood, they could hold out for–

  All her HUD's calculations went in one ear and out the other. Her mouth slowly opened as she stared up at the screens. To the northeast, a line of Aud had grabbed the corpses of their kin and held them in front of themselves. The line of bodies dragging across the ground might've been the most disturbing thing Re-5 saw.

  In that skirmish, anyway. So long as she survived this, common sense would tell her to expect worse later down the line.

  Treating the dead like meat shields was an unfairly successful choice. The sudden appearance of a vanguard threw the targeting programs into confusion. They pumped out dozens of unnecessary shots before the autonomous intelligences wrangled them into order.

  What good was that when the marked targets were already dead? Those who had adopted the new tactic became near-stationary.

  Others at the front of the charge copied those Aud without delay. Re-5's had to stop herself from laughing out loud at the perfect irony. If there was one thing the Aud had that humans didn't, it was bodies.

  The Aud continued advancing, dragging prone masses of fur into place. Some of the meat shields even looked like they were still alive, clinging to life by threads.

  She grabbed an officer running by. "What in--I can't find any record in my data. Yours?"

  His HUD was of a lesser and older make. But she'd been an officer with only a couple more privileges until recently. They should've had access to almost the same amount and kind of information. His head shake reminded her of the stifling unease gripping her chest.

  "It's something new, sir. I'll recruit some techs to record what they can."

  She released him. Questioning Qa-3 revealed he had a similar unfamiliarity with whatever was happening. He looked frustrated he couldn't provide an answer. She patted him on the back and almost told him she felt the same way. No--this was not a time to reveal self-doubt and self-recrimination. Her fingers danced across the console.

  "Gunnery crew, change your priority targeting markers back to the falling Aud. Don't fire at targets from the northern horde anymore unless you can guarantee a hit." The bastards up there couldn't use their dead and dying as shields. Some relief that was.

  Doing that left the assembling horde unchallenged. Re-5 assumed that was how the Aud would see it. The front was bold or stupid enough–she didn't care which–to abandon their shields and charge forward, overtaking the others. There existed cautious exceptions, but like the green pinpricks, they were too few.

  They would extort the utmost from their smallest advantages. As it so happened, human intelligence was by no means a small advantage. The turrets swung back, striking the Aud with burning and bone-shattering punishment.

  If there were any smart ones among them, they'd realize that they'd left behind the horde and the body shields. Both blankets of safety couldn't aid them now that they were far ahead.

  It was only the start. Aud were pack animals. Threaten one, and they all came forth. The rest abandoned their carried protections and joined the stampede. How quaint. The enemy'd discovered a new method to wage warfare. And if not for their instincts, the crew would have trouble on their hands before long. Her lips curled in disgust.

  Whites, oranges, and yellows covered ground at a swift pace and lost numbers. The total still alive was insurmountable. Or it would be, if the Nyx Breaker weren't hiding one last surprise under its armor. The gunnery crew only employed two AWS weapons to repel the Aud. After checking off a series of conditions, they were ready to bring a third into play.

  Packed targets presented themselves. Too many of them. Too many for her to try counting. Almost too many for the autonomous intelligences, too. They experienced a brief lag now when running the simulations.

  With the number of targets increasing, the distance between them and the Nyx Breaker kept shrinking. This'd be a death sentence in any other circumstance.

  At some point, the Aud really needed to learn that no matter how skewed these encounters got, humanity would never be hopeless in close ranges. Cornered animals bit the hardest.

  In a moment that lasted longer than it had any right to, she savored the order on her tongue.

  "This is Acting Sitesman Re-5. Activate the launchers."

  So far, hundreds of hatches remained closed, displaying empty mounts. They weren't holding electrics and sonics in reserve. If there ever was a place for that, it wasn't here. Every electric channeled explosive output. Sonics only quieted when their belts ran empty.

  But there was no reason to hold back any further. With an almost palpable presence, they opened, and another turret type rose from each of them. These were both sleek and bulky to accommodate the larger load. One of the new launchers was enough to inspire unease whichever way it pointed.

  Not only were hundreds coming to bear in every direction Aud came from, but they were on a Titan's scale. Each turret could dwarf an Aud, and their ammunition would crush a careless serviceman's foot if dropped.

  The barrels chambered a cylinder in unison, picked a marker, and fired. Unassuming containers sailed far above before arching. Some struck Aud like sonic munitions. Some rolled between rubble and bodies. The salvo interspersed throughout the oncoming superhorde neatly.

  No Aud slowed in reaction to the new projectiles. They rushed right past until every canister was deep within their disorganized ranks. The metal casings of those on the ground contracted as another wave of cylinders launched overhead. Untapped payloads were about to become very tapped.

  Hmm. That one sounded better in her head.

  Cylinders were handy and provided many effects. Some had greater versatility than others, but they all played their roles. Take the flash cylinder. Its priority was to blind and disorient Aud, but was this all it could do? Of course not. It distracted handily, too. The explosions it made were louder than the largest sonic emplacements.

  That said, the result was more important to the First Ray than the mechanism or cause. Though the Nyx Breaker had an impressive variety in its stores, it only launched one kind.

  The cylinder in question was one of the simplest at their disposal. The Nyx Breaker didn't need lots of things. No point in distractions, routing the superhorde, or even making space. There weren't enough cylinders in the world for that.

  What they needed was chaos. As much of it as possible. Big booms.

  The first salvo detonated. A loose ring of calcifying stone and fire flared up. The heat mirage was strong enough to make shadows dance on the tunnel's walls. Perceiving any details with the naked eye would've been impossible.

  Weaker Aud closest to the cylinders perished. Most with enough distance between them and the explosions withstood it better. Their suffering was still plain to see.

  Most servicemen could tell the difference between electric and combustion cylinder burns. Electrics blanketed targets in painful black. Combustion cylinders pushed past the fur to cook the more vulnerable meat beneath. Organs and musculature tightened, and in the weaker Aud, they melted.

  Those that survived stumbled around as if blinded--some might've actually been. They knocked into others and tripped over each other and the environment. A chain reaction of tumblers ruined the charge.

  Sonics and electrics preyed on the lull to knock more markers off the ledger. No one wore so much as a hesitant quirk of the lips. They weren't finished yet, not with thousands still to go.

  The second salvo hit and exploded. Another half-formed charge fell apart, and the Aud suffered more losses. Distance closed regardless. Nothing mattered but the behemoth of scutumsteel before them. Not their injuries, not their dead, not their dying. What did it smell like outside?

  "The frontmost Aud are close enough for orbs. Want me to inform the gunnery crew it's time to switch cylinders, sir?"

  When had Qa-3 climbed off the sitesman's platform again? Her officer was holding out his hand again and hanging from the edge. This time, she grunted while hoisting him up the rest of the way.

  "Do it. Oh, and stay up here, will you? It'll make our work easier."

  "I may get called away to personally--"

  "If it's about new physical data, a courier or runner can bring it up. It's what they're for. You know you can address everything else with your communicator from here."

  He broke protocol-perfect posture to lean against the railings while studying her. "Sir, the same applies to you. If you discover a need for my aid while I'm not up here, a quick call could sort that out."

  "The benefits of doing this should outweigh those of standard procedure."

  Qa-3's studying look became almost piercing, like he was undressing her. Re-5 hoped her cheeks stayed free of any blush. Now wasn't the time to feel guilty over a decision made while under several pressures. It genuinely should accommodate her needs better. That was the point of his role as her aide, wasn't it? Like hers had been for Ze-4?

  Make the sitesman's work easier through every means necessary and available.

  "What're you doing? Q-Quit your staring."

  "I'm only contemplating whether--"

  "Contemplate whatever you like without standing still like an idiot to stare me down, will you? There's still work that needs doing."

  "So be it, sir."

  Stretchy orbs that flexed while carpeting the air made up the third salvo. Not metal casings the size of grown humans, which felt disappointing in comparison to watch. She could live with that. Rationale told her those orbs would make themselves impressive in a few moments.

  The air resistance became too much halfway through their arc. Their membranes split to release a bouncy gel that soaked the superhorde. Again, the Aud either failed to or chose not to react to it.

  The gels dissolved and turned sticky on impact, coating targets left and right. They absorbed heat from the Aud and jolts from their movements. Explosions only came when they would've felt burning, scalding even, to the touch.

  Each concussive shock shredded through fur and flesh with equally vicious power. A hundred whites, dozens of oranges, and dozens of yellows vanished in the blaze.

  Qa-3 and Re-5's heads pressed together as they watched the same screen on the console. Three green pinpricks vanished from the latest fur scan. When that happened, an unacknowledged sense of victory permeated the command compartment.

  As the Aud closed the gap, the crew depleted their concussive ordnance. Each salvo produced fantastic results, but she had to worry whether they'd be better spent later. Their goal wasn't to leave as much damage behind as possible.

  It was to return home with as many of the original crew as they could. So firing everything off with something resembling reckless abandon now...

  Her assistant shared her concerns. "The echo room needs to finish soon. We'll abandon this position and begin anew elsewhere if they can't live up to our needs. But by the time we're ready to start again, it'll likely be too late for survivors. Return, in that case?" He sounded as bitter as she felt.

  Hearing it from someone else helped her reevaluate their aims. The Nyx Breaker scouted Fort Io. Attempted to report its fall. Sent drones ahead of their return to inform the Directory as soon as possible. What other obligations did they need to meet?

  Ze-4 hadn't received any orders on survivors, much less potential survivors. They couldn't verify yet if anyone was even left in the west apart from them. Staying would allow them to find out, while exposing them to a similar amount of danger.

  Not the smartest decision. This entire venture had been a product of Ze-4's initiative. He'd been the first of them to pay a price for it.

  Could they do the same? Would they? It'd take a single order, and the pilots would turn the Nyx Breaker right back around. The echo room would shut down its operations. Every crewmember would hear from her that their assignment was complete. After returning to the greater western tunnel entrance to collapse it, they could go home.

  Did she dare?

  No.

  It wasn't that she had a choice, or that she did dare to make this choice. She was Acting Sitesman Re-5. Serviceman of the First Ray, and the One-Light Directory. She'd pledged her life to humanity.

  The "as long as she served in the military" clause never seemed all that important. If she left the First after compulsory service, she'd continue doing so elsewhere.

  Right now, she was still in the military. She had other, unspoken obligations. The crew had lost the right to think that way when they piloted the Nyx Breaker out of its mechatronics complex. She had too. Humanity, not them, came first.

  Suppose there existed a slight chance. A minuscule one, even, that a survivor'd discovered something. Information that could save the Last Light and the last bastion outpost from destruction. Or data that could give them a genuine edge over the Aud.

  She should sacrifice herself and the crew in a heartbeat to see that come to pass. More than just her crew would come home safe.

  "We're staying. Even if we relocate, we won't finish the scans in time to save anyone."

  She couldn't gauge his reaction, and they ended up sharing gazes while she tried to. He didn't seem to mind. Looked lighter, too. Her taking the decision out of his hands had to have done something good.

  They directed the skirmish, going through the motions. A power generator had overloaded, and new parts had to get delivered to it. An engineer needed to service it. A tech had to check after the repairs to ensure the software wouldn't fritz. Other problems. Their reserves were getting low--they could supplement munitions meant for other turrets.

  Overhead screens displayed vast grooves running through the superhorde. She wanted there to--she jumped when her HUD routed a call from her communicator.

  The echo room. She keyed open the request fast enough to feel whiplash. She leaned on the sitesman's console while the same Ancient from last call came up. He sounded jubilant. Too loud. Utterly--

  "--found one! We found one!"