From the far end of the corridor’s bend, the sound of something being sliced by a sword, followed by a crashing noise, echoed.

Soon after, Teresa’s voice reached us.

“All done. Please, come this way.”

Her voice was unchanged, showing no signs of injury or fatigue.

Looks like she’s fine.

Using her voice as a signal, we proceeded around the corner of the corridor, and the previously narrow path opened up into a small room about the size of six tatami mats.

Directly opposite the corridor we came from, there was another passage leading further inside—it looked just like the similar spots we passed earlier.

The room had a bit of height, so ideally, it would be a good place to take a breather… but standing there was Teresa, still gripping her sword, alert and cautious even after the battle had ended.

A few piles of undead bones lay in the corner of the room, but it seemed we still couldn’t afford to drop our guard.

“Thanks for the effort. Are you hurt?”

“I’m fine. Was everything alright on your end?”

“There were two Wraiths that showed up in the corridor. Looks like the undead forces are running thin… Shall we take a break?”

“No, let’s keep going. Is everyone alright with that?”

When Teresa asked, we all nodded, and she began walking toward the corridor ahead.

We followed after her with a slight delay.

It’s been about 30 minutes since we entered the passage after descending the well.

As we continued through the narrow corridor, we came upon another small room like before, and it seemed a few undead were lurking there.

Since Teresa, who was leading, had already taken them all out, we didn’t get to see the action, but they didn’t seem very strong.

No one said it aloud, but we all had a sense of what was going on.

Of course, I did too.

Those undead were probably corpses brought down here and turned.

But it’s not exactly easy to bring corpses down such a narrow corridor.

Just carrying a body down a well is no simple task.

But… what if those bodies were children?

They’d be much easier to transport than adult corpses.

And there were so many of them just above…

…It’s a disgusting thought.

Well, anyway.

At any rate, we continued moving through this underground space, but the layout wasn’t a straight path.

We’d walk a bit, then turn a corner, come to one of those small undead-filled rooms, then move forward again, hit another bend, then another small room… it was a repeating pattern.

Seriana explained along the way that the layout was designed so that invaders couldn’t take advantage of numbers, while defenders could properly hold their ground.

In a typical castle or fortress, there are usually hidden paths for defenders to replenish their forces, and attackers often aim for those during sieges. But in this place, that didn’t seem necessary.

After all, the defenders were undead.

We could detect both zombies and wraiths, preventing all surprise attacks—but under normal circumstances, that wouldn’t be possible.

If someone on the invading side died in one of these repeated battles, they’d be added to the defending forces as another undead.

Destroying the corridor wouldn’t be easy either—it was paved and couldn’t be demolished so simply. And if you fumbled, a wraith might come flying over the walls and attack…

That’s probably why Teresa was pushing forward quickly.

Still, for a place that isn’t even in regular use, they went to extreme lengths to construct this…

What’s waiting for us deeper inside?

◇

“That looks like the deepest point.”

We’d passed through a few more small rooms, each repeating the same scene.

But this time, it was different.

We exited a small room, turned down a corridor just ahead—and saw a passage stretching about ten meters long, with a room visible at the far end.

Something inside was giving off light, and that light was spilling out into the hallway.

Seeing it, Fiora murmured in a low voice.

“…It looks just like the royal capital’s research facility.”

“Ah… You took me there once. I thought this looked familiar—it was that place, huh?”

The royal capital’s research facility.

Fiora once guided me there—it also served as the management center for the capital’s barrier and various magical tools.

Magic essence channels were drawn into the floor, walls, and ceiling, causing the entire hall to emit a faint glow.

Though the scale was different, this corridor, these rooms, and that room up ahead looked very similar.

“That brings back memories… That place had Ragyuola’s Claws installed. We can’t see it from here, but I’d guess that room has something installed to sustain this space too.”

While listening to me, Fiora had a nostalgic look on her face, but quickly grew serious as she discussed the possible function of the room ahead.

“There are five undead inside that room. We’ll probably have to fight, but are we ready?”

“Yes. I can only sense them gathering magic essence—there’s no sign of other effects activating. Sera, can you shoot them from here with your bow?”

“Hmm? I can try, but… you sure? I can’t see the target. I’ll probably just hit the wall. Think it’ll collapse?”

Was she planning to use 【Danrem’s Thread】 to blow through it and short out the system?

But that thing has serious physical power too. Is it really okay to use it down here?

“If it works, we could cut the lines in the wall or ceiling. As for a collapse… lend me that, would you?”

Saying that, Fiora pointed to the 【Dragon’s Lung】 I had on my chest.

Ah… so she had a plan after all.

I nodded and handed her the 【Dragon’s Lung】.

————————————————————————————————————————————————————————-

Sera ・Blessing・【Hideout】+1 【Prayer】【Mira’s Blessing】【Water’s Garment】 Blessed Item・【Floating Orb】+1【Shadow Sword】+1【Scarlet Bee Needle】【Fairy’s Eye】【Dragon’s Lung】【Amber Sword】【Danrem’s Thread】【Serpent’s Tail】【Ankle Bracelet】【Amber Shield】【Purple Wings】【Red Sword】【Monkey’s Arm】・8 cards

Seriana・【Area Detection】・【】・0 cards

Elena・【】・【Green Fang】【Amber Sword】・4 cards

Alec・【Strong Strike】・【Red Shield】【Fierce Horned Trumpet】・10 cards