After a little while of exploring the upper levels of these maintenance tunnels, we eventually came across a waste tunnel that led outside into a drainage ditch and found the enormous walls of the depot just on the other side of it.

We were well past those blockades now. I thought the depot looked dreadfully huge when spotting it in the distance on the train ride here, but it was nothing compared to standing right before it. It was like gazing up at a mountain; its sleek dark metal walls refracted little sunlight, and the ambient electrical sounds coming from the depot's giant power cables that branched into the abandoned city were close and deafening enough to make my fur stand up. Of course, we had little time to gawk because Aaron said he spotted some watch towers close by, so keeping low in the ditch was our best bet in sneaking inside undetected.

"Well…we finally made it," I said, keeping to the sloped wall of the ditch with my body low to the sludgy ground. "But how do you suggest getting inside? It looks fortified on literally every angle I have seen."

"Their security is brutal, but it has its holes," Aaron assured, still keeping to the front as he led me along. "They plopped this thing right on top of the town. We'll find another pipe leading underneath the depot and make our way inside without any detection. Assuming that the pipes aren't sealed off down the line, at any rate…"

While that was a concern, I was more fixated on Aaron's choice of words when regarding the depot, and I sensed that he had no figurative meaning behind them. "What do you mean 'plopped'?"

Aaron didn't stop trudging, though he did look back at me in response to my question. "Oh, right; forgot you weren't here during the first days," he realised. "Early on in the Combine's occupation, portal storms were still pretty rampant across the planet—something that they took full advantage of. Those storms made it easier for them to transport supplies and even pre-assembled structures to Earth quickly and to dozens of locations at once. This big eyesore was one of those buildings, and it quite literally fell from the sky and landed where it is now. It was technically a controlled fall, mind you, but that made no difference to poor souls that were still in between the depot and the ground when it appeared…"

The more I learned about the Combine the viler and more apathetic I was coming to understand them. I struggled to comment on what I heard, so I just said nothing as we continued making our way through all this runoff, and neither did Aaron for that matter. I think we unwittingly shared a moment of silence for all of those humans who never got the chance to escape the depot's fall—if they even realised what was happening at all.

In no time at all, we found a drainage pipe that led underneath the walls of the depot. It was just as large as the one before, and me and Aaron both hurriedly climbed inside, successfully fleeing from the open without any issue. The pipeway possessed the same character and clutter as did most of the other tunnels we explored beneath this city, so this latest excursion wasn't too eventful. We couldn't be certain whether or not we slipped past the walls of the depot yet, but we were inclined to continue as long as we could until we couldn't any longer—which did eventually come.

At about the three three-hundred metre mark, the tunnel came to an abrupt halt when we saw that a cave-in of some kind prevented passage entirely. This would have been more discouraging had we not passed a stairway a dozen metres back, so we settled on returning to it to see where it would lead us. Remarkably, there was still power lighting the dreary stairway as we climbed a good ten flights before eventually reaching the top, only to be met with a much more deliberate obstruction.

Another dark metal wall had been built directly into the wide hallway we emerged onto, standing out egregiously amongst the original, fractured architecture in the room. A rectangular door made up of three large angular pieces was squarely in the centre of this wall, an obvious entryway, but Aaron had to keep us out of sight of it while he checked to see if any cameras were built into the ceiling. Once he was sure that there weren't, we strode up to the door and were left with the problem of figuring out a way past it because there were no handles or knobs on the door to speak of.

"Oh brilliant," I said, a little dismayed. "Do you know how to open one of these?"

"I do, but I lack the means to do so properly," Aaron said, though he didn't look discouraged.

"Do you need some kind of key?"

"Kind of," Aaron said, standing closer to the door before sticking his finger into a small hole that softly glowed orange right off to the side of the door. "Soldiers and other units got little imprints in their fingers that allow them to operate these doors freely. It helps to keep unassimilated earthlings out of their business, and I never managed to get one of those micro-planted thingies in my fingers to do that."

He then began to widen his stance in front of the door while shrugging his shoulders, which confused me a little, but his intentions became much clearer once he tilted his torso and grabbed the lower right panel with his hands. "So, we gotta use what's been given to make ends meet."

With all of his might, Aaron then heaved backwards with a mighty pull as his hands gripped the panel, which was turning white with stress. It took a suspenseful couple of seconds, but the metal began to strain and ratchet in the direction Aaron was pulling. Two of the three panels that made up the door began to close in on each other like the binder of a book, jerking with tremendous strain, but Aaron managed to physically pry open the door—at least half of it.

I was no less amazed at his strength now as I was when jumping onto the train. "Aaron, how are you able to…?"

Aaron's grip on the folded panels began to wane slightly, which made me realise that he was keeping it open and was losing his strength. Red in the face, Aaron grunted and looked at me with great urgency. "Go on, lassie, quickly now! Don't make an old man tire himself out!"

The strain in his voice forced me to run and slide underneath the opening he created for me, and the door then loudly shut behind me as Aaron let go. I was now in the resuming section of the hall, but I immediately ran back to the door and put my face near the narrow window. "Aaron?" I prompted, only for him to stumble into view while contorting his back after his arduous feat.

He smiled wearily at me as he came up to the glass. "It doesn't look like you and I are gonna go in through this way together, lassie," he said, muffled by the barrier between us. "I'm gonna have to find my own way inside."

"But you said no more splitting up…?" I recalled, sounding much more desperate than I thought I would.

Aaron looked distressed as well but shook his head in resignation. "This might not be as easy as we'd like, Krystal. You've got much better odds at keeping out of sight than me. We'll meet up at the equipment storage annexe. You know what to look for, right?"

"The room with the melting happy-face sign above it. Right by the unloading platform…" I recited, disheartened that this was the route we were taking. "Where are you going to go? How many other entrances can there be?"

"Plenty if you know where to look," Aaron reassured. "I'm more than able to look after myself; you just gotta worry about getting there and staying out of sight."

I could have argued with him about this, but I knew we didn't have the time for it should patrols be regular in this area. My ears often contradicted how confident I wanted to present myself, but I had to remain poised about this. Aaron had extensive knowledge about the Combine; if anybody would be able to fend them off, I knew it would be him.

"Do you promise you will be there when I will?" I asked, putting my hand up to the glass. Aaron smiled and mirrored my gesture.

"I'll probably end up beating you there. How's that sound?"

"Don't make this a competition, please," I begged, though it did manage a weary laugh out of me.

"If you truly insist," Aaron shrugged, though he didn't appear completely adhering to my plea with that competitive stare he maintained on me. I, with great reluctance, backed away from the door and allowed Aaron to hurry back down the steps from where we both came, leaving me alone behind enemy lines. Splitting up was something I truly wasn't ready for soon after my horrible encounters in the sewers, but I understood when plans needed to be improvised—even when I hated it.

I ran off in the other direction down this empty hall with my machine gun drawn, keeping a sharp eye and mind out for any enemies close by. Decay and clutter of all kinds littered the many corners and crevices of this neglected subterranean space, which reminded me of some kind of metro station with its rounded ceiling and tiled floor. I based this assumption entirely on what metro stations looked like in my universe, so this area could have been anything to the people of this world before the Combine repurposed it for their needs.

I explored this winding area for a short while longer before I arrived at another impasse. The hall ended with a set of two simple closed doors, but one of the imprint readers that Aaron had pointed out to me was currently secured to the handles, acting as a pseudo lock of sorts. I tried pulling at the doors with no success, leaving me to scratch my head as to what to do next right until my ear led me to look up at the ceiling after picking up the faint sound of a breeze and saw an air duct of some kind just nine feet off the ground with a grate covering it.

I wasn't left with much choice but to see if I could climb up in there and see where it would lead me. This was not a very sanitary option, but you tend to become indifferent when you've spent a good part of the morning crawling through sewage. I managed to jump up to the meshed cover and pop it out of its fixture with a good tug of my body weight before I pulled myself right up into the confining metal shaft, which was thankfully big enough for me to fit.

I was cramped and hardly had space to lift my head, but I was able to crawl decently enough as I made my way through this claustrophobic corridor in the direction of the whistling breeze. I managed to crank the torch out from my belt which helped with visibility, but hardly improved my ease of movement. Before long, though, a new source of light revealed itself further up the vent, which also happened to be where the breeze was coming from.

I made sure to turn my torch off as I crawled closer to the end of this shaft, which felt like it took ages to reach as my anticipation climbed higher with every inch I made. Before long, I finally crept to the edge of the vent. What awaited me outside made the air fly out of my lungs.

An enormous, dark indoor complex revealed itself with a tall ceiling that rivalled a skyscraper's height. There appeared to be no ground or floor, just a harrowing dark chasm that looked bottomless given the haze of the abyss illuminated by lights that stretched down for what also seemed like forever, tripling its dizzying effect on my befuddled mind. However, a large network of tracks was suspended above the chasm, interlinking and branching out into different tunnels around the complex, and one of those razor trains happened to be rolling along these tracks slowly and diligently as it crisscrossed across the junction in my view.

I backed up from the ledge as an initial response to seeing just how high up I was. I didn't quite know what to expect when finally entering this place, but this went way beyond anything I could have anticipated. The Combine truly understood how to make you feel small and pitiful when in their presence, and this was just a regional supply depot. I dreaded seeing what their citadels looked like now after beholding all of this.

I soon worked up the nerve to return to the edge of this vent and braved a lengthier gaze downward to see if I had any leverage at all to work with, and much to my surprise I found another ledge down below with some guardrails on it. It wasn't too bad of a drop-down, so I decided I would try to reach it. I had little wiggle room to orient myself where I could grip the end of the vent and shimmy my body out, but I managed to perform one of the most vertigo-inducing pullovers I had ever done.

I dangled with my hands gripping the ledge of the vent, keeping my eyes focused on the platform below. I took a deep breath and swung my legs backwards and then forwards, letting go of the vent as I soared down before landing on the metal surface on my hands and feet. My tail swished and jittered from the adrenaline as I stood up straight, affording myself a moment to relax a little after pulling off that meticulous feat that could have easily gone awry if I didn't time my release precisely. That moment passed quickly when the horn from the moving train nearby reminded me that this wasn't a safe place to idle and pushed me to keep moving.

The grated surface I was on was wide and long, covering the entire length of the wall it was fixed to—which was about half a sports stadium in length. I had to find that loading platform Aaron had described to me, which was likely where that train was heading. I was naturally inclined to follow it, and the suspended pathway I was on led in that very direction.

There was virtually no cover to hide behind on this platform aside from the occasional row of tall metal crates covered in tarps. I was completely exposed and would take nothing less than a sentry looking in my direction to see me and trip an alarm, which only motivated me to keep moving fast. As I did this, I took a wayward glance back at where I came from, and saw that the vent that I emerged from had actually been part of an original human structure that had been severed through and with the Combine wall haphazardly built on top of it. Aaron was right in that there were holes in their security; perhaps they thought that door by the staircase truly was enough to keep out intruders.

Nearing the end of this empty pathway, which was running parallel to the tracks that rounded the same corner into another tunnel, I was beginning to wonder where all the personnel were. Aaron had warned that there would be Combine soldiers and affiliates here, but I couldn't sense any close by. All the better for me, I guess, but it was strange. Perhaps this metal alloy abundant in Combine structures continued to block my telepathy, which forced me to watch my step and remain vigilant should that be the case.

Seeing nobody ahead again, I dashed for the smaller passageway that ran perpendicularly to the tunnel the train was slowly cruising through. Ceiling lights illuminated the pathway while a series of windows to the left of me provided a view of the train travelling down the dimly lit tunnel. I slowed my pace some to both catch my breath a little and to remain steady so I would not run into any personnel should there be any hidden from view up ahead.

Windows on the right side looked over a sublevel that seemed to run underneath the tunnel. It was a wide-open space that I paid little attention to as I tried to keep my head down should anybody see me through the windows that flanked me on either side. I thought this fear had been realised by the time I made it about halfway through this passageway when a deafening siren suddenly wailed somewhere in the complex, nearly making me jump out of my pelt because it was so frightening.

I reactively dropped to the floor, believing I had been spotted through these windows somehow. I desperately began thinking of some kind of strategy for escape until I heard an eerily familiar voice boom throughout the depot. "WARNING. OVERWATCH ACKNOWLEDGES EXOGEN BREACH. MALIGNANT FORCE CONFIRMED. CONTACT ON ROUTE TO PLATELET TRACK IN SUBSECTOR A4. INTERNAL STABILISATION TEAMS DEPLOYED. EXECUTE CONTAINMENT PROCEDURE AND REPORT. NEUTRALISE. CAUTERISE. STABILISE."

That was the same voice belonging to the little floating robot that probed me before I was captured and hauled away on a train. Nothing inside her announcement conveyed anything encouraging, especially if it was specifically addressing me, and I had no reason not to assume that. I rose back up to my feet, preparing to run and find any cover when I heard some commotion happening down below. I glimpsed out the windows to my right to see a whole squad of what I presumed to be soldiers storming the open area down below. They wielded large grey rifles and wore heavy-padded dark-bluish grey uniforms and helmeted filtered masks over their heads and faces, and their eyes glowed a cold blue.

All their backs were turned to me, but I presumed that they were en route to apprehend me at the end of the tunnel. To my surprise, they all stopped when about nine of them could be seen from my position, kneeling and aiming their weapons at something I could not see due to an obstruction in the architecture. I was able to sense their thoughts, and they all were off-puttingly identical to each other. I could hear them audibly exchanging directives with one another as they got into their defensive formations, and although they were difficult to discern through their filters, their words were exactly what they were thinking. I have never encountered any sentient being who did that, so it was quite unnerving to hear these soldiers do this.

I started to wonder why they had stopped and assumed the positions they were in; I thought that perhaps they were waiting for me to come into their line of fire, but my assumption began to change once a loud combustion could be heard down below where the soldiers were. They all then began to open fire seconds after, unleashing a flurry of what looked like pulse-energy bolts from their weapons to something directly ahead of them.

A blood-curdling battle cry could then be heard as a huge mass came into view, charging the soldiers using a large metal sheet to deflect the gunfire. The charger rammed into the squad with tremendous force, making them scatter, though several of them were offlined in the attack. I gasped when I realised that it was Aaron who was attacking these soldiers, and I was now beholden to a side of him that I had not seen before.

Aaron brutally beat these soldiers with little mercy, taking full advantage of his towering build as he swung his arms together like clubs, knocking his considerably smaller opposition away like they were weightless. He even hurled a few away with only one hand clutching around their heads, further demonstrating how much of a powerhouse he was. It was an incredible spectacle seeing him fighting so proficiently, which was an overtly stark contrast to the friendly and uplifting individual he usually was.

The use of his makeshift shield for deflecting gunfire soon became obsolete once he managed to disarm all of the soldiers during his rampage, even breaking one of them in two over his knee while he was wrangling a specific soldier. I felt their cerebral silence; Aaron had killed every troop dispatched to stop him, which shocked me. He looked over the mess he had made for a moment, breathing heavily with his fists clenched, but all the mangled and twisted bodies reassured him that they weren't a problem anymore.

I was tempted to knock on the glass to get his attention, but I sensed another wave of soldiers coming in the opposite direction, closing in quickly as their chatter grew louder in my mind. Aaron seemed to notice them too and quickly picked up one of the rifles a soldier had dropped and began firing in that direction before running off down below me and out of sight. The soldiers could be seen chasing after him moments later, prompting me to duck out of sight should they spot me.

I learned two things after watching everything I had just witnessed: the Combine did not seem to make any reference to me in any of their chatter—implying that I still wasn't a known target—and that Aaron was a true force to be reckoned with. I did worry though how much this would impede our promised meeting at the storage annexe by the loading bay. While I worried for Aaron greatly, I had to take advantage of the diversion he was creating—whether it was intentional on his part or otherwise.