Once someone reached B-rank or higher as an explorer, most of them were faster running on their own than relying on a car. Of course, since it was still human-powered, maintaining top speed wasn’t as easy as rolling along on tires—but back when Saitou Megumi had been training at an explorer academy, one of the instructors, an explorer who had been A-rank at the time, had said this:

—We’re basically like oversized fleas or grasshoppers.

She’d thought, What kind of thing do you say to a teenage girl? but now that she considered it, it wasn’t entirely wrong.

It was a trope you sometimes saw in manga: fleas could jump distances up to two hundred times their body length. Scaled up to human size, that would mean a single leap of three hundred meters.

Back then, she’d thought, That’s ridiculous.

Now—if she really went all out, she found herself thinking it might actually be possible.

“Is the stream still running? Hand the camera over to me. Sanagi, it’s dangerous here—secure that self-important old man in the suit and wait in the car. Ironically enough, now that the dungeon is gone, this place is probably the safest. Nanami, work with the branch office staff and do what needs to be done. Then return to back us up immediately.”

Irselia, the silver-haired elf who had just come back from the parking lot, issued her orders to Megumi and the others in a tone that brooked no argument. Cold, sharp—and dependable.

Despite her girl-like appearance, the confidence and certainty in her voice made it clear that she was a woman far older than Megumi and the rest.

“Megumi, Airi, and Chizuru—you’re coming with me. We’re heading to suppress the Dungeon Stampede occurring in the Noumi Dungeon. If it’s the type where a horde of monsters comes pouring out, we’ll split up and deal with them as quickly as possible—but I think a big one is going to appear. Prepare yourselves.”

“…Why do you think that?”

Airi tilted her head, a question mark practically floating above it. Megumi, unable to fully process how quickly the situation was escalating, could only focus on chewing over Irselia’s words.

In situations this tight, it was oddly enough Midou Airi—the healer—who tended to be the most clear-headed.

“Because this isn’t a normal Dungeon Stampede. If mana had been slowly building up until it crossed the threshold, there should’ve been signs right up until the very edge—an increase in monsters inside the dungeon, or their strengthening, for example. That’s just my guess, though.”

Having taken the streaming camera from Shinguu Sanagi, Irselia used the belt extending from the main unit to secure it beneath her chin, around the space between her collarbones, as she continued.

“I see. So this time—it’s because Assemblyman Sasamori somehow erased the Kamioka Dungeon, causing its mana to rush all at once into the Sugai Dungeon and the Noumi Dungeon, which were connected to it… no, maybe it’s the other way around. If two dungeons went into Stampede, then logically speaking, it makes more sense to assume all three dungeons were connected. They were connected, mana flowed through them, and that triggered the Stampede… is that it.”

Hm, Kagurazaka Chizuru, her hair tied back in a samurai-style ponytail, nodded.

She sounded like she understood, but Megumi knew that this was less a matter of strict logic and more of a rough, intuitive grasp. Chizuru had a knack for getting the “so basically this is what’s going on” part right, but the finer details were usually glossed over.

Besides, there was no guarantee that what Tia—the holy sword wielder—had said was actually true. And yet, regardless of the truth of Tia’s words, the Kamioka Dungeon really had vanished, and reports of a Dungeon Stampede were coming in.

“Probably.”

Irselia nodded briefly, took a mobile terminal from her pocket, and let out a small, dry smile. Then she addressed the viewers of the stream.

“Everyone watching—you can hear me, right? This is an emergency. Nothing is clear yet, but we’ve received information that one of S City’s three major dungeons, the Kamioka Dungeon that we were just exploring, has vanished, and that a Dungeon Stampede is occurring in the remaining Sugai Dungeon and Noumi Dungeon. Tooru and the holy sword wielder woman are heading to the Sugai Dungeon. We’re about to move toward the Noumi Dungeon. However, those of us here can’t independently verify the information. Right now… there are eighty thousand people watching. We’re going to rely on collective intelligence. If you can investigate the situation, or if you’re watching the stream from a nearby location, post it in the comments. Sanagi and Nanami will sift through it and pass it to Airi. Airi, relay whatever information you think is important back to us.”

The elf’s keen, lucid gaze settled on Megumi.

At some point, Megumi realized she had been holding her beloved greatsword in her arms. She tightened her grip on the hilt, exhaled slowly, drew in a breath—and then gave a clear nod.

“All right. Let’s go. We’ll follow Irselia’s instructions.”

“Relax. I, Irselia Lumiester, an S-rank explorer, will protect you. Megumi and Chizuru, as the vanguard, follow my orders especially closely. Airi, don’t leave my side. Understood? Then—let’s move.”

In half a second, they nodded to one another, each gripping their weapon tightly, and leapt.

One jump—three hundred meters.

No wonder my old classmates were afraid of us, Megumi thought with a wry smile somewhere deep in her chest.

◇◇◇

When she put her full strength into a leap, she really could advance about three hundred meters. Her top speed was probably around a hundred meters per second, but just like a fired bullet gradually lost kinetic energy, her velocity bled away in the interval before her next step.

Averaged out, that came to a movement speed of around 180 kilometers per hour.

If they pushed themselves, A-rank explorers could maintain that pace for about an hour, but the straight-line distance from the Kamioka Dungeon to the Noumi Dungeon—no need to stick to roads when you weren’t using a car—didn’t require anywhere near that long.

Dungeons defied general rules, so there was no fixed pattern to where they appeared. For example, Tokyo’s famous “Shinjuku Dungeon” had its entrance inside a station, while the “Mount Fuji Dungeon” opened at the fifth station of the mountain.

S City’s Kamioka Dungeon had its entrance near the foot of a mountain in the suburbs, while the Sugai Dungeon was apparently located along a prefectural road at a somewhat higher elevation.

And then there was the Noumi Dungeon.

Worst of all, it was inside the city.

Right around the dungeon entrance there were, as expected, only things like a parking lot and a dungeon branch office—but step just slightly outside that area, and it turned into a bustling downtown district of a regional city.

And near the Noumi Dungeon entrance itself, there was something enormous.

It was visible even from two kilometers away. A monster like a three-headed serpent. From a reptilian torso the size of a detached house, three snakes—each looking to be around thirty meters long—were growing out.

“Incoming report from the scene! Estimated upper-tier S-rank—Hydra species! There’s a high chance several local explorers are still inside the Noumi Dungeon!”

Airi’s voice rang out. No—strictly speaking, it wasn’t a voice. At this speed, ordinary sound—mere vibrations in the air—couldn’t function properly.

She was delivering her words directly to Megumi’s ears through mana, a form of kotodama.¹

“That’s literally a kaiju…!”

It looked like something straight out of the Yamata-no-Orochi myth. Despite having a reptilian torso, it somehow stood upright, supported by two legs and a massive tail. Three serpents sprouted from its body, slamming against the ground over and over—but the scale of it was simply too great. The nearby dungeon branch office, along with most of the surrounding man-made structures, had already been utterly pulverized.

“On that building’s rooftop!”

A building about two hundred meters from the Hydra was indicated. Maintaining the momentum of their high-speed movement, they leapt onto the roof of a nearby structure, used the tip of a utility pole as a foothold, and jumped again. Megumi had put a bit too much force into it, so she angled the flat of her greatsword forward, using air resistance to bleed off speed.

Landing successful.

Chizuru reached the building slightly ahead of Megumi, with Irselia and Airi arriving just moments later.

The area seemed to be suffering from a blackout, likely caused by the Hydra’s rampage. City lights were still visible farther away, but the immediate surroundings were shrouded in deep darkness.

Even so, as proof of its status as a powerful monster, the area around the Hydra glowed with mana interference, its colossal form eerily illuminated against the night.

“Even a flood would’ve been better than this. With a Hydra species, you need to sever all three heads at the same time. For now, I’ll draw its attention. I’ll fire one shot—if you think you can make it, close in and take the heads.”

Clank! With a sharp mechanical sound, Irselia unfolded the bow she had been carrying. She drew back a string formed entirely of mana. What she was about to fire wasn’t a physical arrow, but a magic arrow shaped from mana itself.

She had boasted that it was a legendary-grade bow—crafted by bringing materials from an S-rank dungeon back to the elven nation in Atlantis, then forged using arcane techniques impossible for modern humanity to reproduce, incorporating elements inspired by Earth’s science. Honestly… it was the kind of thing anyone would want to brag about.

Its name, according to her—

The magic bow “Miming Vrede.”²

Irselia used every ounce of her slender frame to draw the string taut. The mana-formed “arrow” began to radiate a blinding light. The mana that had been diffusing into the surroundings gradually converged, intensifying until it was almost painful to look at directly.

“Devour.”

The shot and the impact were almost simultaneous.

Faster than a bullet and more powerful than artillery, the arrow punched straight through one of the Hydra’s heads—leaving a single streak of light across the night sky before vanishing.

“Now!”

Irselia shouted, but she didn’t need to. The shot from the magic bow was undoubtedly far stronger than Megumi’s strongest slash, but from the look of it, the Hydra’s necks could be severed even without that much power.

Without sparing even a moment to meet Chizuru’s eyes, Megumi fixed her gaze solely on the Hydra and leapt from the rooftop. Her next foothold was the roof of a shop slightly lower than the building, then the top of a utility pole, and then the roof of yet another structure.

And then—the Hydra was right in front of her.

Chizuru was on the left. The head Irselia had pierced was already beginning to regenerate. Megumi’s target was the right head. One final leap. She launched herself as if punching through a wall of air.

“Haaah—!”

With a tearing shout, she charged in and swung her greatsword.

There was no named technique. If anything, it was a single, all-in slash fueled by sheer spirit. She closed to point-blank range against the Hydra’s grotesquely massive body, its scale warping her sense of distance—and cut with everything she had.

She cut it.

She could cut it.

The unmistakable sensation of severing the Hydra’s neck thicker than her sword. Holding her follow-through, Megumi glanced left. She saw Chizuru sever the left head with an aerial iaijutsu slash.

“Magic defense!”

Airi’s Kotodama reached her. Of course, she’d already intended to. Having leapt up to strike the Hydra’s head and still suspended in midair with nothing to brace against, Megumi nevertheless gathered every ounce of her mana and braced for the impact.

The time lag was less than an instant. The arrow from Miming Vrede blew apart the center head, which had already begun to regenerate.

The power was excessive—at the moment of impact, an overwhelming shockwave, a mana blast that would probably have torn her body to pieces without magical defense, slammed into her and sent her flying. But she’d been prepared, so there was no problem.

She was hurled through the air like a doll thrown by a tantrum-throwing child. But to an A-rank explorer, being blown away by a shockwave was hardly a big deal.

Because there was such a thing as air resistance.

In everyday life, you never noticed it—but under high-speed combat conditions, the atmosphere became a wall. No matter how high your initial velocity, the air resistance acting on a human body was enormous. To overcome it required techniques that parted the air with mana—and Megumi could only manage that for the brief instant of an attack.

And so, when she was being blown away like this, that wall of air became a cushion.

Her speed dropped almost instantly.

She twisted her body in midair to regain her posture and landed against the wall of a building she was about to collide with, using the spring of her whole body and her mana to absorb the impact. For a split second she hesitated—whether to return to the rooftop where Irselia and Airi were, or to head for the Noumi Dungeon entrance where the Hydra had appeared—and then chose the latter.

The Hydra couldn’t have been rampaging for very long, but even so, the government building adjacent to the Noumi Dungeon had been crushed, and the surrounding area was in ruins. How many victims were there already—and how many could still be saved?

Those thoughts in Megumi’s head never quite formed into words; they were more a vague sense of things. Precisely because of that, they were her unvarnished feelings.

She had entered an explorer training school funded by national money. There were people there in the same situation as her, and she had made close friends. With support from state-employed “teacher” and from former explorer like Hamamatsu Nanami, she had formed the explorer clan Anthem, become its leader, and was enjoying what she did.

So she had to give something back.

She had an obligation to save the ordinary people who had once treated her like a monster.

“Is anyone—anyone there!? If you’ve been caught up in this and you’re still alive—!”

In just three steps she covered the distance she’d been blown away, casting a glance at the Hydra’s corpse—about the size of a single-family house—as she checked the damage.

For now, there were no victims in sight. Megumi thought for a moment and was about to check the remains of the dungeon branch office the Hydra had destroyed—when she noticed something off.

Why… hadn’t the Hydra’s body disappeared?

Monsters spawned by dungeons were supposed to vanish upon death, leaving behind a magic core or rare drops. Monsters produced by a Dungeon Stampede were no exception.

And yet, when she turned back, the massive reptilian torso of the Hydra was still there—still standing upright, not even collapsed. There was no sign of it dissolving into motes of mana.

“Leader! Get away!”

Chizuru’s shout rang out. This time, it was an actual voice.

One she distinctly remembered hearing not long ago—a cry bordering on a scream.

“…What?”

She looked just in time to see the Hydra’s torso swelling, about to burst.

The torso—about the size of a detached house—was torn open from the inside, spewing viscera and blood like some horrific accident, and from it emerged a five-headed Hydra, one size smaller than before.

This is bad, she realized instinctively.

Even though its overall volume was smaller, the total amount of mana she felt against her skin had increased instead. Which meant the density was higher. It had learned from the shot fired by Miming Vrede—that unless its mana was more densely packed, it would be pierced straight through. That was why it hadn’t reacted at all to Megumi’s or Chizuru’s approach…

Her thoughts only got that far.

A tsunami-like deluge of entrails and blood slammed into her head-on, and Megumi’s consciousness was wiped out for several seconds. Several seconds—against a Dungeon Stampede monster.

Ah. I’m dead, she thought.

1. kotodama is basically collective name for power of words in japanese spirituality where its believed that words, names, etc hold spiritual power.
2. Kanji for it translates to “Wrath of the Forest God.” I had to google quite a bit and it seems this refers to Miming, the Satyr of the woods from Gesta Danorum. It means ‘Miming’s Wrath’ in Danish.)