The small adventuring party of one engineer, one brave Roomba scout, and a train of crawling support vehicles made their way through darkened tunnels filled with gasses unsuitable for supporting life. No one in the party seemed concerned about this, even the weakest link with biological lungs that needed oxygen. This was the start of a job, and he was happy to get started.

The first task started back at the entrance. He needed to clear the larger delivery tunnel so that he could bring in larger loads. This wasn't a difficult task; he just hadn't brought the right tools before. Today, he had an electric winch that ran off his crawler generator and plenty of synthetic fiber rope. The bright purple rope from Cortland International was expensive, but when you needed something strong and light, it was the material you wanted. Once he'd attached the rope to the capsule blocking the tunnel, it only took a minute to pull it and load it onto a wheeled carriage. One of his crawlers moved it to the side and parked it.

Annoyingly, there was another capsule beyond that one. A few minutes later, it, too, was parked to the side of the room, and Milo was running down to hook the cable to a third capsule. He cursed the idiot who loaded all of these capsules into the delivery tube. Capsule after capsule had to be cleared, five in all. He got the last one pulled out and placed in the rows of capsules. Then he wondered if using the capsules to block the entrance was the whole point. That was horribly inefficient. If Milo wanted to make sure no one used this tube system to gain access to the facility, he'd have just tossed an explosive charge inside and blown the whole thing up. He didn't have cataclysmite in the real world, which was a shame. It was a much more destructive substance than C-4 or TNT.

Milo stopped what he was doing and suddenly wondered what was in the capsules. He started examining them, looking for differences between them and the other capsule stored in the room. Capsule number three had a suspicious radio transmitter added to the front of the capsule. Milo took a deep breath, grabbed his scanners, and carefully got to work. He was aided by the device having an access port for programming. As he suspected, the device was connected to a detonator inside the capsule. His heart skipped several beats as he saw that the program was still running. The only reason things hadn't gone boom was a constant resetting of the 60-second timer when it got to 5 seconds left. A signal from inside the facility was interfering with the detonator doing its job. It was up to Milo to make that interference a permanent failure. He was able to first reprogram the device to cease its countdown and, after that, uncouple it from the capsule. Examining the capsule took some time, making sure he didn't set off a booby trap.

Inside each capsule was five tons of C-4 in convenient sixty-pound packages. Two hours later, he had checked out all five capsules and determined there were no more detonators to worry about. He was, however, concerned about twenty-five tons of C-4 sitting on the doorstep of the only way out of the facility. It took another hour to tow each of the capsules down to the end of the blocked maglev tunnel. It was still a hazard, but less of one. His large tunnelers got another job to do. Tons of loose rock from drilling his tunnels was moved to the end of the maglev tunnel until there was a fifty-foot wall of loose rock between the explosives and the front door. That would have to do for now.

With the blockage cleared, and the explosives moved, he could finally get to his real work and led his larger crawlers down the delivery tunnel and into the building. Max beeped impatiently at times and tried to send signals to the crawlers, who stupidly ignored him. Milo noticed and spent a few minutes adding access codes to Max and programming the crawlers to accept his second-in-command's orders. Max was much smarter than the simple crawlers, with the map of the facility in his memory. Now, Milo could tell Max what he needed, and Max could shepherd the crawlers around. That would let Milo focus on the real work. Which is this case, he was getting through a set of doors blocking him from a large section labeled 'Engineering and Power.'

These doors had controls that Milo could access after dismantling a panel. They lacked the power to open, but that's what his mobile generators were for. Ten minutes later, the doors opened, and he disconnected the power, ensuring they couldn't shut behind him. Finding the explosives was making him even more paranoid than normal. Max had led him down a spiral ramp that dropped the equivalent of five floors in the Habitat, ending in a room with only two large double doors. According to Max's map, the next room was immense, the size of an entire floor of Section E, with no intervening walls.

As Milo walked into the dark, man-made cavern, he was in heaven. It reminded him of the Deep Rock Engineering Compound. (Before he blew it up.) He walked along one wall where ten magnificent diesel engines were arrayed. Each took up the space of a city block and was four stories tall. Coupled with each diesel engine was an electrical generator that could generate enough power to run several Habitat sections. Those generators fed energy to transformers that regulated the electrical power before sending it to a massive bank of storage batteries.

Inspecting the batteries, Milo was impressed, both with their sheer size and their ability to generate some of their own power. The system's core was a series of several thousand modular Nano Diamond Batteries using nuclear fuel encapsulated in synthetic diamond. On their own, this system could generate a large amount of power for the next hundred years. As a storage device, they could be charged by the ten massive electrical generators to provide backup power for the facility. Currently, they had no stored energy, and the generated electricity was all that was powering the facility, according to his limited knowledge.

Exploring further, he found a small building. It was roughly 50 feet in diameter and three stories tall. A clear dome covered the top story, while the bottom two stories had no windows and only one door. A small bit of light reflected off the dome, showing that some machinery inside must have power. The doorway was curious; it was at the end of a short, 10' passage that jutted out from the building, constructed of welded metal and obviously added on. The arc welds of the seams were not done by a professional welder. Some areas had been caulked and coated with a coat of latex sealer. Milo's best theory was that it was an airlock added to the small building. That implied a breathable atmosphere, and someone who was working here after the neutral gas atmosphere replaced normal air in the large room.

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The panel was simple, and with the push of a button, the door came unlatched, and he could pull it open. Stepping inside, he pulled it shut after a light in the ceiling came on. As soon as he sealed the door, air started circulating, and then a green light appeared above the other door. He opened it and stepped inside, closing it behind him. Dim lighting came on, activated by motion detectors. The bottom layer was a confusing mess. Along one wall, filing cabinets and data storage shelves had been ransacked and everything removed. In other places, he saw boxes of hastily packed paperwork, books, cans of food and coffee, toilet paper, and bottled water. Two restrooms with a shower stall between them were along one wall. Milo tested the water supply. It ran brown and red for a minute, evidence of rust and bacteria in the stale water, before running clean. Stairs curved around the wall to the second floor. Max had followed him inside and used the ramp that paralleled the stairs to ascend as well.

If the first room had been basement storage, this was a living room. A large couch with blankets and pillows sat in the front of the room, with two gaming consoles and a 96" screen. Game cartridges were scattered on the floor, and some on a shelving unit next to the couch. Milo tested the air, found it good to breathe, and retracted his helmet. There was a musty smell in the room. Max ran around the room, scooping up dust, crumbs, and anything else it could find. Milo put away all the game cartridges and moved things off the floor. This floor had been converted to living quarters hastily. The small refrigerator, microwave oven, and kitchen appliances were all portable. There was no sink on this level, and dirty dishes were piled on a countertop. He left Max to complete his cleanup and went to the top floor.

The lights started to dim, and from below, he heard the sound of an engine starting up. The lights brightened. Emergency power of some sort had kicked in. Two large tables were set up in the center, with piles of technical manuals and notepads stacked around the edges. In the center were hundreds of post-it notes with reminders about jobs that needed to be done. Water testing, cables that needed replacing, ideas for scavenging materials from one part of the facility to fix what wasn't working. It reminded Milo of his own work in Section E. The difference was that often, these notes were addressed to people, as if the writer expected them on the job soon.

Dan: I don't have the know-how to splice high voltage cables that are cut between the generators and the Nuclear Batterie Storage Unit. Storage 47 has extra cable; can we just run new lines? Welding something carrying that much power seems risky. Out of my depth here, buddy. This is ASAP when you get in.

Sheila: I've done what I could for Rusty, but I'm so busy with everything else that I will have to leave the rest of his education to you. Could you find me when you get here, and I'll give you an idea of where he's at?

Plummer's hose? Draino? Why the hell does the toilet keep plugging up? There's only one toilet being used; the drains can't be clogged already!

Dorian: Look at the kernel, please! He needs to know what a joke is. Getting a burn on my ass from a security drone is NOT FUNNY! He needs to know this.

Dan: Here's how I want to restart the diesel power. I managed to tow a generator truck up near #1. I have a large tank of compressed air for input, and we just vent the exhaust into the room. Once the #1 diesel engine turns over, we'll have all the power we need to run everything in the room. (After welding those cables.)

There were dozens of notes written by the same person to different people. Milo focused on the ones that had to do with power generation, found the written plans and diagrams, and one binder full of spec sheets for the massive diesel engines. He became absorbed in the projects, reviewing the original layout and how the unknown engineer wanted to restart the system. One thing bothered him: Air. How did they draw air for the engines to run on and vent the exhaust? Especially when the room was filled with argonite gas? He tore through the system and finally went back outside to climb around in the dark with a spotlight, looking at the diesel engines themselves. Huge exhaust systems ran to one large export pipe. Similarly, air was brought in through one pipe and distributed to all ten machines. Export went to one corner, and import came from another. Walking to a corner, Milo saw that both walls were made of collapsium. These were exterior walls. In each corner was a massive collapsium column going from floor to ceiling. The export and import pipes were connected to these obviously hollow columns.

Something that hadn't been obvious because of the darkness occurred to him. He grabbed Max and connected his tail to the maps inside his little sidekick. The security/cleaning drone could go to many parts of the complex. Milo compressed the maps further to gain perspective on the whole complex. The full columns were visible on the maps on each level. They were hollow collapsium support columns for the entire structure. Very similar to those used at the corners shared by the Habitat sectors. He didn't need his computer to verify his assumption, but he did it anyway, just to be sure.

All the data came to one conclusion: The collapsium supports of this complex were directly under the supports at the corners of Section E. Air and exhaust fumes from this complex moved up and down from the Habitat. It made sense to Milo. How do you hide a huge complex like this? Stick a Habitat on top. The Habitat had a large number of air intakes and exhaust stacks. Thinking hard, he wandered back to the little command center to start going through everything and plan his next moves.

Above him, his friends and Belinda lived. He checked his email and saw a message from Belinda. "Daddy is still being an ass and won't let me have my pod. The gang was by today. Eric is bypassing Daddy to get them in. Daddy is busy arguing with Uncle Victor, who keeps showing up to talk to him about one thing or another. We're having another party tomorrow. Come by when you can." He sent a non-committal message back. He just didn't know.

He needed to know what this place was and if it was a treasure or a threat to the people above him.