The walls were up. They seemed solid enough.

Steven Chen finally had an opportunity to learn what the Hub was and what it could do. He looked over to where Mendez had laid herself down, getting a well-earned rest after just saving both their asses with her shooting. He'd felt like a coward handing over the gun, but he'd been right to do so. She was the better shot. It made sense; she'd grown up in Alabama, and his parents had moved the family to Birmingham only five years ago.

He had a lot of questions.

The Hub. Just what was it? Was it just a collection of hardware and software, or maybe an interface to a larger system? Did it have a mind of its own? Did it have a connection to the alien equivalent of the Internet?

He took a deep breath and decided to start his investigation. "Hub," he called out, "display admin options."

"Please confirm your identity," the Hub replied.

He'd been through this before; best to get it over with. "Cadet Steven Chen," he said.

"Confirmed. Initiate Cadet Steven Chen is the highest-ranking member of Defense Force United States Army. Access granted."

"Finally," Steven said to himself. He scrolled through the various options. The screen required precise selection. "Okay, first off. Can we do some sort of minority report gesture interface?"

"State the name or category of the desired report," the Hub said.

He shook his head at the misinterpretation of his rambling words. Although, what reports were there to see?

"Cancel request," he said.

He tried to organize his thoughts, going over the recent events in his mind. Something had bothered him.

"Mendez," he called over his shoulder to the prone cadet.

"Yeah?" she murmured, "you see the enemy coming?"

"The coast is clear," he assured her, "but that's what I wanted to ask you about. Remember when we were out on the street?"

"It was like ten minutes ago, Chen," she said.

"Am I right in saying you warned me about the raptors coming before the Hub?"

"Yeah, I could see them coming around the corner about three blocks away," she said.

Steven thought about the implications of that. The Hub had told them what the range of the scanners was. Thirteen hundred feet or about four hundred meters, but that's the width of the circle, right?

"Hub," he said, "display map of sensor range."

"Acknowledged."

"What is the approximate area in acres?"

"Using the local Defense Force unit of measurement designated as an acre, this scanning range encompasses thirty-two point seven acres."

"This confirms it, Mendez," he said. "The scanner only covers about halfway up the second block from where we salvaged that Raptor."

"Well, you're at the controls," she said, still resting on the ground, "ask it if we can extend the range."

"The range of the sensor function may be upgraded on the Defense Force Territory control interface. Would you like to create that panel?"

Interesting, he thought. The Hub had responded to an indirect question. That was new behavior. He nodded, then added, "Yes," unsure if the Hub could see or understand what a nod was.

"Select the location of the Defense Force Territory control interface," the Hub said.

The Hub projected the familiar blue-green outline on the spuncrete wall directly across from his position.

Steven walked over, examining the projection. "Here should be good," he said.

"Acknowledged. Creating Defense Force Territory control interface," the Hub responded.

The wall shimmered as the interface materialized, forming a sleek, touch-sensitive panel. Steven reached out, activating the interface. He was happy to have a tactile interface again, even if it was just a flat sheet. He read through the available options.

"A lot of sensor upgrades available, and more that are greyed out," he said as Mendez approached to stand next to him.

"A one-way panel," she read. "Like a one-way mirror, I suppose?"

"Wall on one side, window on the other," he said, expanding the details.

"What's that symbol there on the requirements?" Mendez asked, pointing to the screen.

He tapped the area, which caused the upgrade information screen to fill the display.

"Defense Force Credits?" Mendez said, frowning at the screen.

"Defense Force Credits, or DFC, are required for most territory management functions," the Hub responded. "They are also used to initiate the Quantum Probability calculation function."

"Quantum Probability calculation?" Mendez repeated, eyebrows raised. "That sounds complicated."

He tried to think of an explanation but figured they should probably just keep asking the Hub as a first step. "Hub, explain the Quantum Probability calculation function."

"The Quantum Probability Generator is capable of creating equipment which is not currently available due to lack of schematic or material. This serves two primary functions: it utilizes unwanted or excess materials and components, and it creates unpredictable and potentially unique variations of standard equipment."

His eyes widened.

"This is an awful lot like a video game," Mendez said.

"Exactly," he said. In fact, it was the first thing he'd said when they saw the things that the emblem was keeping track of. He'd been right from the start, but there was no need to gloat.

"But why?" she said.

"Let's find out," he said. "Hub, feel free to interrupt me to dispute or affirm anything I'm about to say," Steven started.

"Acknowledged," the Hub replied.

"Am I right in thinking that if we use a system labeled as Defense Force credits, the enemy uses a similar system?" Steven asked.

"That is correct. The opposing force system could be labeled Incursion Force Credits," the Hub confirmed.

"Could be?" Steven raised an eyebrow.

"The incursion force does not use the local language model," the Hub clarified.

"I think it's saying that it just made up the phrase for our benefit," Mendez added.

"That is correct," the Hub responded.

"Okay, so we're both operating under the same system. But the enemy got a massive head start on us," Steven said, trying to piece it all together.

"That would be an accurate assessment," the Hub affirmed.

"When we created this Hub, we were prompted to give our group a name, we chose 'United States Army'. Does that mean that anyone else who makes their own Hub would have their own Defense Force?" Steven asked.

"Correct," the Hub replied.

"Is that true of the enemy?" Steven pressed.

"Correct. Each incursion site is a separate incursion force group. However, all groups belong to the same allegiance," the Hub explained.

"Right," Steven said, contemplating the implications. "That does put us at a bit of a disadvantage, in terms of geopolitics."

"It seems so," Mendez said, nodding. "We’re just one group among many, and the enemy is coordinated across multiple fronts."

"And as far as we know, this is the only Defense Force Hub," Steven added.

"There is no information available to determine the validity of that statement," the Hub interjected.

"You can't talk to other hubs?" Mendez asked.

"Each Defense Force is a separate entity with a separate Hub station," the Hub replied.

"Can a Defense Force create a station that acts like a hub but is still within the same network?" he inquired.

"Affirmative. There are multiple modules which would fit that criteria. That requires a higher tier access," the Hub stated.

"So it's further down on the tech tree," he mused. "Is there a tech tree? Does spending credits on Defense Force technology unlock additional available technology?"

"On the assumption that 'tree' refers to the branching nature of such a life form, that is an accurate assessment. Do you wish for the Defense Force Territory control interface to generate a representation of this tech tree?" the Hub asked.

"Yes," he said, eager to see what new possibilities might open up.

The new wall-mounted screen's interface changed, displaying a complex, branching diagram with various nodes representing different technologies and upgrades. Some nodes were clearly defined, while others were greyed out, indicating they were yet to be unlocked. But the organization left a lot to be desired.

"This is a mess," Mendez said, shaking her head. "Chen, can you understand this spaghetti?"

He gave his own shake of the head in response. The 'tree' was incomprehensible, the Hub could learn a thing or two from some video games, he thought.

"Hub, can you put the available options at the top?" he asked. "Even if we don't have enough credits to unlock them yet. Then add the corresponding technology icons connected below." He tried to picture tech trees from games he had played in his head. "Try to keep orthogonal edges," he added, hoping the Hub knew what orthogonal meant.

Did you know this text is from a different site? Read the official version to support the creator.

"Adjusting display," the Hub responded.

The diagram reconfigured itself, with the available options now neatly arranged at the top. Lines connected the available options to their respective subsequent technologies, forming a more organized and visually appealing tree structure. The edges were straight, creating a clear and coherent flow from top to bottom.

"Better," he said, nodding in approval. "Much easier to understand."

"That's great," Mendez said. "But before you dig into that, Chen, what other enhancements like this screen do we have access to? Maybe there's some other screen I can check out while you figure the technology path out for us."

"That information is available on the Defense Force Territory control interface," the Hub said.

"Put it on the screen then," she said.

The interface displayed another set of options, showcasing different enhancements and additional screens they could access. Mendez scanned through the list and quickly found something of interest.

"This one looks promising," she said, pointing to a specific option.

"Hub Management," he read aloud, eyebrows shooting up at the prospect of controlling the Hub directly.

"Can you put that screen right here?" Mendez asked the Hub.

Once again, the Hub projected a blue-green outline, a slightly different shape than the Defense Force screen.

"Align it with the other screen," Mendez directed. "Perfect. Make it, please."

He had a close-up view of how the screen was created this time. The spuncrete wall shimmered, seemingly melting and reforming, extruding the shape of the new interface in the location Mendez had picked. The surface began to take on a new luminance and became the now familiar display. A display showing a new set of options focused on resource storage, construction optimization strategies, and a list of upgrades for the Hub itself. It had its own tech tree, mirroring the layout he had just organized.

"Looks like we can optimize how we store and use resources," Mendez said. "And there are upgrades for the Hub too."

He thought back to the list of available screens that Mendez had chosen from. "We might as well add the equipment management screen while we're at it," he suggested.

Mendez nodded. "Good idea. Hub, can you create the equipment management screen next to the other two?"

"Acknowledged. Select the location for the Equipment Management Interface," the Hub responded.

Mendez pointed to a spot adjacent to the existing screens. The blue-green outline appeared, and the spuncrete wall began to shimmer and reshape once more. Within moments, a new screen materialized, displaying options for equipment upgrades, inventory management, and weapon customization.

"This is the most complicated system of them all," he said, noting the dazzling array of types of equipment and the seemingly endless variety each contained.

"Chen," Mendez said, her eyes still on the new Hub management screen, "here's the Quantum Probability Generator upgrade. We don't have the materials to make it yet."

"Every gun has its own tech tree," he said, scrolling through the endless options.

"Let's look at that later," Mendez said, "help me figure out which modules to we should focus on."

"The random generator does sound interesting. There are still two raptors that I need to salvage," he pointed out.

"I want to make all of these, honestly," she said. "Speaking of salvage, we can make a salvage module and it can salvage anything you can fit into the port. Look at the options, all of them are available if we have the materials."

"They don't cost DFC either," he noted.

Mendez returned to the list of available modules. "Component factory—this lets us make any component that we have the schematic for," she said. "Equipment reconfiguration—that's what you use to add and remove components on equipment. There are separate modules that create weapons, armor, and tools, like your salvage tool, I'll assume. All of the other options on the tech tree are grayed out, though."

"We'll have to make them to see what that unlocks," he said. "Do we have enough for that salvage module?"

"It only takes basic materials," she said, scanning the requirements. "No components. We have plenty."

"Okay, you make the module and I'll start cutting up the raptors into pieces small enough to fit."

Mendez nodded and initiated the creation of the salvage module. The Hub projected its blue-green laser light, outlining the salvage module as it was formed. Materials emerged from the Hub itself, out of the same port where they had withdrawn their armor and the G-100 pistols. There was clearly some sort of gravitational or electromagnetic manipulation at play in this process, Chen assumed. The components assembled themselves with precision, guided by invisible forces. Piece by piece, the module took shape, integrating seamlessly into the Hub’s structure.

He watched in fascination as the construction process unfolded. "Incredible," he muttered, appreciating the advanced technology at work.

"Module's ready," Mendez called out to him once the construction was complete. The new interface was now part of the Hub, and he took note of the size of the intake port.

"I could just watch it do that all day," he said.

"That's nice, but you've got raptors to disassemble," Mendez replied.

"Yes ma'am," he replied with a hint of sarcasm.

Steven grabbed his Field Salvage Tool and headed back out to the fallen raptors. He worked quickly; the tool made it clear where to cut in order to avoid damaging extractable components. There were a few sections he needed to trim down in order to fit into the new port. The tool guided his cuts with precision, and he soon had a collection of neatly cut pieces ready for processing.

He hauled the first load back to the Hub and carefully inserted a piece into the salvage port. The module greedily consumed everything he offered. In short order, there was nothing left of the two raptors Mendez had taken out.

"We're going to need more raptors," he said.

"Seven Defense Force Credits have been added to the United States Army registry," the Hub announced.

"How many do we have?" he asked.

"Nine DFC." it said.

He let out a breath. Should they make the random generator module and roll the dice with those nine credits? They could get anything. They could also get nothing of any value.

"Chen," Mendez said, interrupting his thoughts, "we need to have a discussion about what we want from this. What our expectations are."

"Okay," he said, stalling for time as he shifted his train of thought internally.

Mendez folded her arms, her expression serious. "We need a plan, Chen. A real plan. What do you think we should do next?"

"Keep building," he replied. "Expand our territory, upgrade our defenses, and gather more resources. The Hub's giving us the tools to fight back."

"I get that," Mendez said, "but we can't do this alone. We're just two ROTC cadets in the middle of an enemy-occupied city. We need to make contact with the Army, or any military, join up with them if we can."

He frowned. "And how do you propose we do that? We're cut off from everyone. All comms are down. The city's been evacuated, and the enemy's control is spreading."

"Not all comms are down. Remember what Sergeant Lister said, they were going to train us on military radio protocol once we got to the command center. We can start by making one," Mendez suggested.

"One what?" he said.

"A radio," she said, "you're studying electrical engineering, right? You should be able to cobble something together."

He considered it. "I might be able to, but it'll take time and parts we don't have. Maybe we can find a radio somewhere in the city. There have to be abandoned police stations, fire departments, or even electronics stores."

Mendez pointed at him, a gesture indicating he had just said something right. "If we can find a working radio or even parts to build one, we can make contact with the Army, or any military. Let them know we're here and what we have."

He nodded slowly. "Alright, that makes sense. But we still need to gather more resources and defend our territory in the meantime. We can't let our guard down."

"Agreed," Mendez said. "You're right, we're going to need more enemy parts. They give us credits for killing them, and we get materials and credits for processing them."

"To do that, we need to diversify our weapons. Something for close range, mid-range, and long-range encounters," he explained, holding up his hands to indicate relative ranges. "Pistol, shotgun, rifle." It was like he was demonstrating the size of a fish.

"We already have the G-100 pistols for close-range, so we're good there," she said, looking at the new equipment screen. "There are so many options, too many to pick."

He glanced at the screen, feeling overwhelmed by the sheer number of choices. "The Hub did a good job suggesting the G-100 earlier," he said. "Hub, can you select a shotgun and a rifle that you can make two of each? Stick with guns that can be reloaded using the same energy packs we already have."

"Affirmative," the Hub responded. "Selecting optimal shotgun and rifle models for current resource availability, reload platform and combat requirements. Shotgun selection, Hammerhead H-6. Rifle selection, Eagle XE-R."

"Great," Steven said. "Hub, initiate construction of two Hammerhead H-6 shotguns and two Eagle XE-R rifles."

The Hub's blue-green glow emanated within the construction chamber, and materials began to emerge from the Hub's port. Within moments, two Hammerhead H-6 shotguns and two Eagle XE-R rifles were constructed and ready for use.

He picked up one of the shotguns, feeling its weight and balance. "Feels solid," he reported for Mendez's benefit.

"Okay, now how are we going to carry all three guns at the same time?" she said, holding up a shotgun in one hand and the rifle in the other.

"Wherever you feel comfortable, I guess," he said. "I keep my pistol down low on my thigh, and you've got yours on your hip."

Both he and Mendez took a few minutes trying out different configurations. The emblem was able to interface with the armor and the weapon, creating what felt like a magnetic link wherever they stuck them. He ended up with both guns on his back, sticking up like antennas. Mendez put the shotgun across her chest, at an angle, and the rifle on her back, lower down. She was able to take out the rifle by reaching back with one hand, whereas he felt more comfortable pulling them out over his shoulder.

"How's that feel?" he asked, watching as Mendez adjusted her setup.

"Not bad," Mendez replied, testing the draw and holster motions. "I can get to the rifle quickly, and the shotgun's right here if I need it in a pinch."

"Same here," he said, flexing his shoulders to make sure the guns were secure. "The magnetic links are strong enough to hold them in place, but they come off easily when I need them."

"Alright," Mendez said, satisfied with their configurations. "Now we need to focus on our enhanced warning system."

He had an idea. "I've been thinking about something like a wearable camera, attached to the helmet, linked to the emblem," he proposed, his engineering mind picturing the setup as he tried to describe it. "Three hundred sixty-degree coverage. Line of sight, I wonder if it could do lidar, radar, and sonar?"

"Hub, can you create a wearable camera system with these specifications?" Mendez asked.

"Affirmative. Desired functions match tool designated JVD-41D. To begin, confirm use of necessary components," the Hub responded.

He glanced at Mendez. "We have enough components, right?"

Mendez nodded. "We do, but it's asking us to confirm that we want to use them."

"Ah, okay, yeah if it does all that," he said.

"Confirm use of components," Mendez said.

"Place desired cover equipment into the input port of the main Hub," it said.

"One at a time I guess?" Mendez said, unstrapping her own helmet.

Steven followed suit, removing his helmet and placing it into the input port. The Hub's blue-green laser scanned the helmet, analyzing its structure and integrating the new components. Within moments, the helmet was returned, now equipped with the advanced sensory system.

Mendez placed her helmet into the port next.

The helmet looked mostly the same. There were new spots, sensors of one type or another, he assumed. They ringed the entire helmet, but it otherwise just looked like a matte black helmet.

He put it back on his head, intent on testing the new features. He tapped his emblem, noting the slight vibrations that indicated the system was active.

"Hub, display a basic visual," he requested.

In response, the emblem invisibly ignited individually targeted dust particles, creating a rudimentary image in front of his eyes. It wasn't a full HUD, but it was enough to show basic information—directional arrows, proximity alerts, and sensor readings.

"Looks like it's working," he said, impressed by the simplicity and effectiveness of the system. "It's not a full HUD, but it gives us the essential data."

Mendez nodded, adjusting her own helmet. "It just hangs there," she said, moving around the afterimage hanging in the air. "Not great on the run but better than nothing, that's for sure."

"Emblem," he said, "verify audio alert on detection of enemy units."

"Warning system active," the voice of the emblem said in his ears. That was still a bit of a disorienting effect he was getting used to.

"Okay so it isn't just the visual warning at least. And with the 360-degree coverage, we won't have any blind spots," he added. "Let's test the different sensor modes."

He cycled through the modes, each one providing a different type of environmental feedback. The emblem displayed the information through the dust particle images, giving them a clear understanding of their surroundings.

"This is incredible," Mendez said, apparently scrolling through the different views herself. "We can see through walls, detect movement, and even map out the terrain."

"I want to see what it's like when we really need it, but I think we’ve got a much better awareness of our environment now," he said.

They spent a few more minutes familiarizing themselves with the new system, testing various scenarios and ensuring they could rely on the sensory feedback.

"So," he said, putting his hands on his knees, preparing to stand up.

"So," Mendez echoed him.

"Should be plenty of daylight left," he said, checking his watch. "There's probably some salvage left on the unit we left out on the street. We can take it from there?"

"Eager to get out there? Try your new toys?" she said.

"A little, yeah," he admitted.

Sounds like a plan," Mendez agreed with a nod. "Let's make sure we get everything we can from that raptor. We need all the resources we can get."

They geared up, double-checking their weapons and equipment. The new systems gave them a renewed sense of confidence, but they knew they still had to be cautious.

He tapped his emblem, bringing up the display. "Not reading anything nearby. Ready?" he asked, adjusting his helmet.

"Ready," Mendez confirmed, gripping her shotgun.

He opened the door.