Arknights: Mobile City

No matter how many times he saw it, Obsidian still thought the Thumb was brutally efficient.

If you were far, it'd shoot you down.

If you were close, it'd smash your skull in with the butt of the gun.

Didn't matter where you ran. You weren't getting away.

While Texas was out sweeping monsters from the perimeter, Obsidian stayed behind, managing Doubts as they worked on construction and began setting up a basic border patrol.

Originally, the City's human-activity zone had a radius of about 200 meters. Now, Obsidian and Texas were working to clear out all monsters within a full kilometer—and establish a functional defensive perimeter.

A one-kilometer radius was Obsidian's current goal. That would give him enough space to build the facilities he needed. And it also happened to be the maximum patrol coverage his Doubts could maintain.

After steady development, he now had 25 Doubts under his command. Five were reserved as a production base and emergency reserve—also doing construction work. The rest were split in two: half assigned to resource gathering, the other half stationed on patrol.

It was just enough to establish a minimal defense across the entire one-kilometer safety ring.

"City walls? Yeah… no materials. And building them would be a nightmare right now. We'll leave that for later."

Obsidian tossed the comment over his shoulder as he walked behind Texas. She, still synced with her Thumb identity, was coolly and mechanically mowing down Sweepers nearby.

And as she killed them… there was a strange kind of pleasure that bubbled up.

Not hatred. Not vengeance. More like a sick, compulsive satisfaction.

Texas thought about this even as she kept slicing through her enemies without hesitation.

Obsidian had mentioned before—identities were alternate versions of oneself, drawn from possible realities. This Thumb identity… it must've had a story of its own.

What kind of life did she live? Was it during the City's prime—when it was still bustling with people and power?

The thought flickered briefly across Texas's mind.

Meanwhile, Obsidian stopped monitoring her performance and went back to his own tasks.

He was reminded again of how important Lunacy was.

Resources out here were limited.

That fact was starting to weigh on him. The problem was a vicious loop.

There was only so much usable steel and salvageable material in the immediate vicinity. But once he reached beyond the six-kilometer mark—that thing might appear again.

Meaning… everything he could safely access was within six kilometers. That also meant: the number of Doubts he could build was capped.

If even one got destroyed—and the body was unrecoverable—that was one fewer unit he'd be able to field.

Obsidian exhaled heavily, stress settling deeper in his chest.

And even the Sweepers weren't dropping much Lunacy anymore. After spending the whole afternoon sweeping the outskirts, he and Texas had only managed to scrape together 100 Lunacy.

Just enough for three gacha pulls.

It wasn't enough. Nowhere near enough.

By dusk, their sweep was complete. Texas disengaged her identity and walked back to the central area with Obsidian.

"Hey, look over there."

Leaning against the windowsill, Obsidian pointed to a newly built hut not far away.

"That's yours for now. It's probably not fancy, but… bear with it, alright?"

His tone was casual. Texas looked at the small wooden house, constructed with Doubts working around the clock. Then she turned back to him.

"Nothing else you need me for?"

She asked the question abruptly, eyes scanning Obsidian's weary face.

But he only shook his head silently.

Texas couldn't help much more. Of that, Obsidian was certain.

They stood like that for several minutes, gazes locked. In the end, she only let out a quiet sigh.

He clearly doesn't want me getting involved too deeply. If that's the case… I'll trust him, for now.

"Then I'll head over. Take care of yourself, alright?"

She said it offhandedly, like a friend making a passing remark. Obsidian, however, nodded seriously in return.

This is my problem. No need to drag others into it.

Once she was gone, Obsidian leaned back against the window, exhaling a long breath.

Something inside him—some sense of responsibility—pushed him to solve the City's problems on his own.

If I can fix it myself, there's no need to ask for help. If even help won't fix it…

Then I'll find a way forward alone.

That had always been his way. Otherwise, wouldn't it have been easier to just export all the City's monsters to Terra?

But he hadn't. Call it old-world values, call it naivety—but Obsidian wasn't ready to put that burden on someone else.

"Alright… the Doubt should be there by now. Time to see what's out there. Hopefully, there's still some hope to be had…"

He exhaled again and shifted his awareness into the Doubt he'd dispatched earlier that morning.

The moment he saw what lay ahead, his pupils constricted.

"Wait—what is… that?"

What stood before him was not a Bloodfiend. Not a Sweeper. Not a Whale. And definitely not an Aberration.

It was… bugs.

Just insects.

But they weren't just a few bugs. They were countless.

An endless swarm of insects blanketing the entire mountainside.

Through the eyes of the Doubt, Obsidian stared dumbly at the horizon. One small robot standing alone—and ahead of it, a ravenous tide of devouring bugs, tearing through everything in sight like locusts from a nightmare.

Then, one massive insect spotted the Doubt.

It slithered toward it, writhing forward with grotesque grace.

Obsidian panicked and tried to escape—but there was nowhere to go. The swarm surrounded them on all sides.

And then, the giant bug descended.

CHOMP.

The Doubt was gone.

Back in his real body, Obsidian's face had gone pale.

What the hell kind of dungeon is this supposed to be?!

He was stunned—on the edge of despair.

Because he knew exactly what he'd just seen.

That thing wasn't from Dawn. It wasn't a regular enemy. It was from Amber Dusk—and its name was:

"Food Chain."

A challenge entirely different from "Doubt," but already categorized at the Dusk level. And Doubt? That was still Dawn.

According to old-world analysis, Midnight was the apocalypse tier. And Dusk… was just one step below that.

As for Food Chain? It symbolized devouring. A swarm-based horror with devastating power, capable of consuming nearly anything in its path.

Worse yet, it had the ability to summon "Fresh Food"—a swarm of lesser amber-colored bugs that devoured everything like a plague.

"No… that's not even the worst part…"

Obsidian sat down heavily on the bed, voice low. But then his head snapped up, eyes widening.

He'd just remembered one critical detail:

That [Food Chain] had been moving toward his safe zone.

Compared to the day before, it had advanced more than 300 meters.

Which meant—at this rate—it would reach the central hut in less than twenty days.

And as things stood now… Obsidian had no way to stop it.

If it arrived—he was dead.

No question about it.

"The pressure's unreal… I need a solution. Fast. If I can't beat it… at least I need to stall it."

After a long silence, Obsidian finally pulled out the Lunacy he'd earned and turned toward the well.

He had no choice. It was time to gamble.

"Alright, Well… Give me a pull!"

Without hesitation, he dumped all 390 Lunacy into the well.

Leaving himself with just 10 Lunacy to his name.

But when he saw the three items the well offered in return—

A wild grin split across his face.

"YA☆DA☆ZE! Jackpot!"