There were more laboratories on the floor, each mirrored copies of the botany lab, but with different focuses.

When they tapped the glass screens in one lab, an image of a horned beetle appeared and there were rows of clear boxes with desiccated insect shells along the far wall. Most had whithered away to dust, but some of the carapaces were intact enough to piece together the creatures they used to be.

"Mountain lemmings." Kait said as they explored another lab, her hand toying with the hologram JD couldn't see from his angle.

"And this is some sort of hare." Fahz added from another table, where the display was flickering and blank but evidently the holographic tech was still functional.

If JD stood at just the right spot, he could see the small shard of light as it reflected off Kait's cornea. It reinforced Fahz's idea that the images were being beamed directly into their eyes, rather than projecting into the air like Baird's more primitive holograms.

In the fifth lab they checked—fish seemed to be the focus in that one—Marcus stood examining the shattered remains of one of the glass displays. After a few seconds he stooped and gingerly plucked a piece of glass off the floor and shone his flashlight into its reflective surface. In the light, JD could see the shimmering lines of circuits and something that looked like a camera lens.

"Baird'll probably want to take a look." His father said as he tucked the glass shard into a pouch on his belt. JD nodded, knowing that even if they brought back nothing else, a sample of that holographic imaging tech would probably make Baird's week.

The labs were numerous, but like the bedrooms on the previous floor, they eventually stopped and only the blank hall laid ahead. They doubled back and descended the stairs to find three more levels of various laboratories. While the first two levels had been concerned with plants and animals, the third and forth seemed focused on a larger variety of topics.

One room was row upon row of desks and chairs, with smaller display panels on each one. JD tried to move one of the chairs and take a better look at a display, but the plastic-like material was brittle and cracked the moment he slid it back over the floor. One of the legs crumpled under its own weight and the chair toppled backwards, splintering the chair back as it hit the floor. The noise was jarring in the relative quiet of the room, making the others whirl to look at him.

"Sorry." He said quickly, kicking the remains of the chair away and watching as the material kept crumbling as it skittered across the floor.

The display remained dark when he tapped it, and he was about to back away to try another panel when it blinked on.

"Huh." JD murmured, leaning in closer and studying the transparent mountain ranges that floated into view in front of him.

"Almost looks like tactical data. Topographical maps and location analysis." Marcus said a few rows away, looking at his own display. "Still can't read any of this though." JD glanced down at the floating mountains lazily spinning in front of him, noting the labels in that odd language.

"Does that look like Vasgari to you, Fahz?" He asked, nodding his head toward the screen. JD could recognize-but not read-quite a few different languages, whether it was the syllabic swirls of the Pesang people or the Cyrillic blocks of Gorasni. Vasgari wasn't all that dissimilar to Gorasni, if he remembered correctly. He knew some part of him recognized the language, but he couldn't be sure where he had seen it, only that it looked achingly familiar.

Fahz glanced up and stared at the display for a moment, then shook his head. "Nah. I've seen plenty of me dad's old medical textbooks to know what Vasgari's supposed to look like, and that's not it."

They had Dave scan what information they could find, then moved on down the hall. They all made guesses for each room's use as they explored: geology, meteorology, astronomy.

"Whatever they were doing down here, they must have had every type of scientist under the sun." Kait said as they left a lab they assumed had been used for some sort of advance technology development. Marcus had collected a few more scraps of tech to bring back to Baird, but JD wasn't holding out hope any of it was useful.

"You know what this reminds me of?" There was a reluctant lilt to his father's voice as he spoke. "Azura. All these laboratories? Scientists?" He gestured to the door of some sort of marine lab as they passed.

JD tilted his head and considered it for a moment. "If the COG had a secret bunker stowed away for the end of the world, it's not hard to believe someone else did too."

"We Vasgari were always very forward-thinking people." Fahz chimed, an overly smug look on his face.

Kait held up a hand, one side of her mouth tugging to the side. "There's a few problems with that theory. First of all, if they were making an emergency fate-of-the-world type bunker, why the hell would they put it underground?"

Fahz made a face. "Where the hell else are you going to put a bunker? Not everyone's got a secret island in their back pocket for the apocalypse."

"Sure, but if they built this place in response to the Locust, why would anyone put it in the centre of a Locust burrow?"

"Who says it was in response to the Locust? Azura was built during the Pendulum Wars." JD countered.

Kait shook her head. "Did anyone have tech like this during the Pendulum Wars?"

"Vasgar invented all sorts of things. Microchips and the like. Smart bunch, we were." Fahz tapped his temple.

"Hate to break it to you," JD gave him a slap on the shoulder. "But I think all that Vasgari intelligence skipped over your twig in the family tree."

"Look," Marcus cut in before Fahz could respond with a jibe on his own. "We're not here to speculate about why this place is here or what purpose it served. There are people in New Ephyra who can do that. We're here to scout it, grab intel, and then go home."

His father was right, of course. They'd been exploring the metal structure for a few hours now, not to mention the hours they had spent marching through the caverns to reach it. JD had expected the mission to be an in-and-out job, a few hours at the most. Already they were way over his initial time estimates, and before long they'd have to consider resting for the night.

Their bickering and theorizing brought to an abrupt end, they carried on with their exploration.

The humming throughout the structure grew stronger and louder with every level they descended. There were areas where things were rattling noisily from the vibrations, and it was clear the shaking was causing minor damage. Some of the glass displays swayed back and for from the ceiling, more of the plastic chairs seemed to disintegrate and crumple into jagged piles on the floor, items that had been sitting on shelves or desks shimmied their way with every vibration to eventually tumble down to the ground.

"All this space and equipment," Kait murmured as they made their way back to the stairs. "But where are the people?"

JD hadn't considered it until then, but Kait raised a good point. They had seen dozens of living quarters and there was space for hundreds of workers in the labs, but they had yet to see another soul inside the structure, or even a body.

Occasionally he would notice small things like a cup sitting on a desk or the way a chair had been left pushed back as though someone had just gotten up to go run an errand. It suddenly made everything seem very eerie, and JD wished Kait hadn't brought it up.

They walked down the stairs and quickly skimmed through a level that appeared to be for recreational purposes. A mess hall, some sort of large open room JD guessed was for assemblies and meetings, and a space that appeared to be meant for exercise and weight lifting, though it didn't look like any fitness equipment they had in the COG gym in New Ephyra. Fahz took a keen interest in one of the weight machines, but let it be when they moved on without him.

The next flight of stairs down didn't lead to another level. Instead it kept winding downwards and JD counted at least 15 flights before they finally found another door. He had wanted to give up on the descent and head back up, but that engine-like rumble was growing stronger with every step and he knew they had to figure out where it was coming from.

"Anyone else really dreading having to hike all the way back up?" Fahz asked rather dejectedly.

"If it makes you feel any better," JD said absently as he tapped at the door's control panel. "At least we don't have to do it in armour."

There was a brief pause. "That does make me feel better, actually." Fahz's tone lightened a little. "Thanks."

"Did...Fahz just thank you?" Kait asked, crossing her arms and leaning on the wall beside the panel.

JD stopped poking the glass for a moment and stared blankly ahead. "You know, I think he idid./i And it was genuine too. Like a real, honest-to-goodness thank you." He made a show of looking stunned as he turned to look at Fahz. "I'm touched."

"Oh yes, I get it. I'm an arsehole, how hysterical. Now," Fahz made a shooing motion with his fingers. "Back to work."

JD was expecting another hallway to appear when the door slid aside, but what greeting him was a wall of hot air and near-deafening sound. Reflexively JD's hand shot up to shield his face from the heat and he ducked his head as if the noise was something he could shy away from.

"I think we found the source of our seismic activity!" He hollered over his shoulder, though he had no idea if they heard him. It was the thunderous rumbling they had been hearing throughout the structure, and now it wasn't dampened by layers of stone or metal. It was raw and uninhibited and it rattled him to his bones.

The floor trembled beneath him and his metal greaves clattered as he walked through the doorway, his hand dropping away as his eyes slowly panned upwards. Dave quickly fluttered passed, floating up to scan and explore, his little optics shifting back and forth excitedly.

The initial blast of heat had been alarming, but it wasn't harmful. JD knew he would be sweating in minutes, but it was no worse that the desert sun up on the surface. At least without their armour they would be more comfortable.

Based on his quick visual assessment of their surroundings, JD surmised that the gargantuan room was circular like all the previous levels. Unlike the previous levels, the ceiling was so far above his head he had to squint to make out the flickering lights, and the walls were not the same monotonous metal-grey that had lined the corridors and laboratories.

Instead of the smooth unspectacular walls, it was a maze of metal pipework and heavy thick tubing, with tanks and pylons lining walkways that weaved their way outwards. Wires and cabling were routed in precise lines along the pipes, connecting electrical panels to machinery.

Ahead of them were massive stacks of what JD could only guess were pistons and some sort of valve system. He didn't know much about engines-that had always been Del's specialty-but it looked like the biggest, loudest, most impressive engine room he had ever seen. It was like someone had taken the bowels of the COGs largest naval warships, grouped them together, and supersized them.

Rubbing his stubbled head and feeling the sweat already staring to bead, JD craned his head back and saw multiple levels extending upwards. The ceiling appeared to slope downwards from the centre of the room where they had entered, ending somewhere far beyond their current location and obscured behind all the machinery.

"Baird should be here." He uttered, his head shaking side to side slowly at the sheer scale of the place. Once they returned topside with Dave's footage and scans, they'd have to physically restrain Baird to stop him from hopping into the first Grindlift and blindly burrowing his way down to this massive contraption. A place like this would be the old man's personal heaven.

"What?!" Kait yelled, leaning towards him so he could hear her. She had a hand cupped around one ear and cringed as she tried to concentrate through the noise.

"I said," JD raised his voice to the volume he regularly used on the battlefield. "Baird should be here!"

Kait blinked a few times at him, her face twisting a little. "iWhat?!/i"

JD shook his head and waved his hand tell her not to worry about it. She shrugged, and JD looked back at Fahz and Marcus.

Fahz was saying something—JD could see him mouthing some sort of obscenity and exclamation—but it was lost in all the rumbling of the machine. Marcus was as stoic and quiet as ever, his eyes narrow and scrutinizing.

With a swing of his arm, JD gestured for them to follow and began marching along the inner wall where the walkway led them in the familiar curving stroll. The open space really helped put into perspective just how large the and truly impressive the structure was. Whatever this place had been, whether it was an emergency end-of-the-world bunker or something else, it was a boggling feat of engineering and technology and Baird was going to ilose his mind/i.

The white noise of the massive engine-whatever its purpose-was easy to get lost in. JD couldn't hear anything or anyone else, and he found himself looking back over his should every twenty steps just to make sure the others were still behind him. It would be a great place for an ambush, with so much sound to cover footsteps and so many nooks and crannies to hide in. His eyes darted from one shadow to another warily, his hand resting on the solid grip of his Boltok.

It was maybe fifteen minutes of walking past the continuous tanks and pipes and wires when they came to some sort of central point where everything parted aside to reveal an empty space on the floor. Across from the seemingly blank area, tucked in the inner wall, was another doorway. This one was wider and taller, like the door to a garage.

Marcus approached the frame and tapped the dim panel beside. With a iwhoosh/i that was covered by the rumbling of the engine, the door split down the middle and slid aside. Fahz held his arms up in victory and relief.

"Thank ifucking/i god!" He yelled, though JD could just barely make him out. "An elevator!"

And that was definitely what it looked like: a large wide elevator with big control displays on the opposing walls.

JD jumped when his father tapped him on the shoulder, having not heard him walk up behind him. Marcus pointed to the flat section on the floor that was void of any of the pipes or cables. It took him a second, then JD realized it was a lift platform, its rails running up the metal scaffolding all the way to the ceiling.

JD nodded in agreement and motioned the group forward to the platform. Tilting his head back, he could see lights glowing at the top and he prodded the control panel until it flashed to life. Tapping the button that seemed to indicate the top level, he watched as railings rose from recessed grooves in the floor. There was a groan and a shudder beneath their feet, and they rose upwards.

The view was a marvel and JD's brain ached just thinking how the Vasgaris had managed to build something so incredible and massive. And how had they done it without anyone detecting it? It must have taken years, decades even, to excavate all the dirt and stone, then build the metal complex in the space. That kind of project would have required billions of dollars, thousands of people, and more resources than JD could even imagine.

And they still had no idea what it was ifor/i.

The top level was incredibly promising. It looked like some sort of control deck, lined with displays-solid blacks ones, not the fragile holographic panels they had seen-and riddled with desks and swaths of buttons and switches and toggles and dials.

Only one display was illuminated and it was at the far end of the level, where the sloping ceiling intersected the floor to create a slanted wall. The display flashed repeatedly, a bright pulsing yellow. At its centre was a symbol JD didn't recognize, but solid black triangle conveyed the universal sign of iwarning!/i, though the small circles floating at the center of each side were unfamiliar.

With two fingers pointing at the display he sent Dave forward to investigate. They all watched as the bot examined the display and the symbol, then zipped over the controls in front of it. There was no standard interface port, JD realized. No place where Dave could jack in and attempt to control the machine.

It wasn't a ihuge/i surprise, really. Not every nation had adopted the standardized data ports, especially when they were introduced so soon before the Locust War. The old UIR missile launch tower hadn't had them, and Jack had needed to access the raw wiring to get into the system. Remembering that, JD began looking for an access hatch, anywhere that exposed the innards to let Dave into the system.

He found a panel with a handle a few feet away and yanked it free. Dave dove in immediately, his arms moving about as he tried to make sense of the circuit boards and cables that lay within.

To JD's surprise, the bot backed away after a full minute, having accomplished nothing. The massive engine rumbled on and Dave just stared at him blankly. There was a brief moment where JD was at a total loss, not knowing what to do if their bot suddenly couldn't do its job.

Marcus stared at the stunned bot for a moment, then JD saw him give a little shrug and reach forward to press a glowing blue button on the console.

Nothing happened.

So Marcus pressed another, and still nothing happened.

Then they were all pressing buttons and throwing switches, regardless of their unknown purpose. Even Dave joined in, a manipulator slowly turning a dial while the other attacked a row of small black toggles.

One minute ticked by, then two. Nothing they did seemed to make any difference in the engine rumble around them. JD huffed and took a step back to survey the panels and displays.

Maybe there was a lock on the system? Some sort of failsafe engaged to prevent tampering? Did they had to find the override so their random button pressing and switch flicking would take effect?

He looked back a the big yellow alert symbol, still flashing steadily.

Staring at it absently while he considered their next course of action, JD almost didn't notice the subtle change to the symbol.

It was still a triangle and still solid black with the three accompanying circles at each side. Or rather, the upper two sides had circles.

A single black chevron hovered where the bottom-most circle had been, and its angular tip pointed downwards.

JD's eyes followed the direction of the pointing chevron and found a pulsing green node in the control panel beneath the display. It had been lost in the sea of buttons, looking no different than many of its fellows, but it flashed in time with the yellow warning screen.

JD pressed it, not really expecting anything to happen. But as soon as he felt it depress the green light went out and there was a sharp pop from within the panel, loud enough to be heard amidst the noise.

He jerked back, startled when the entire control desk shuddered and split apart down the middle, revealing a six-inch gap. Ten wide slots ran down in a column, all empty except for one. With a sharp clunking noise the dark grey rectangular object in the fifth slot ejected and jutted upward.

The others had stopped their rampage across the switches and keys and were staring at him. JD glanced back, apprehension tensing his muscles, then reached out and with a cautious, tentative hand, he grasped the rectangle and lifted it from its cradle. It was solid and weighty and felt warm in his fingers.

JD eased back and flipped the object over in his hands as Dave approached. He held it up while the bot ran his scanner over it, and JD was about to ask Fahz to read off the scan results but the open control panel behind him gave a grinding shriek of metal and slammed itself shut.

The flashing yellow display blinked three more times before fading to darkness. Then in a wave, starting from the centre console where JD had retrieved the rectangle, the buttons, dials and switches all gave one last weak pulse and died.

They had several seconds to share confused looks when distant thunking and squealing echoed through the din. Somewhere around the curve of the structure a valve released a huff of compressed air and the engine gave a low growl like a Minotaur shifting into low gear.

A few more seconds ticked by and the thunderous noise began to ebb, the decibels trickling away as the giant machine began winding down.

They all looked at each other, eyes wide with alarm, then in unison they turned their attention to the object in JD's hand.