As for why such an enormous, hulking, and ferocious variant of Beastkin was called a female Beastkin, even Kate couldn't explain it.
Maybe that berserker just identified as female?
With no clear concept of self-recognized gender, no wonder it was so violent.
The deeper they went, the fewer people remained around Duanmu Huai.
It wasn't because of casualties—rather, the tunnels themselves were structured like tangled roots, splitting into countless branches as they descended. A normal force would have stuck to a single safe passage, but Duanmu Huai didn't need caution. He dispersed his units, sending every squad down a separate tunnel to search and eliminate any lurking threats.
Honestly, from Kate's perspective, splitting up like that was a stupid idea—but she had to admit, these armored warriors were absurdly powerful. Even if they were ambushed, they'd probably be fine.
Before long, the other squads had already scattered into the branching tunnels, leaving Duanmu Huai's small group to follow one of the wider corridors.
"Ahhh… this is so boring."
Bambi lay sprawled across Duanmu Huai's shoulder, yawning.
"The underground sucks—dark, cold, and creepy everywhere. Bambi wants to go lie in the sun and nap…"
"I find it rather fascinating," Ranni said, lifting her head curiously as she observed their surroundings. This was, after all, her first journey beyond her own world to another planet. To her, even the rocks and moss here were worth studying.
"But it's so dull," Anne muttered, stretching her arms. "We barely even get to fight."
Since this campaign was mainly for troop training, the Astral Army handled most of the battles. With their overwhelming firepower, Anne and the others hardly needed to lift a finger—they were basically along for the ride.
"Oh right," Anne suddenly said, grinning as she turned toward Kate.
"Miss Kate, why don't you tell us about the Beastkin—and about this world of yours?"
"This world?" Kate blinked.
"Yeah! Anything's fine! Tell us something interesting!"
"Uh…"
Kate looked at the eager sparkle in Anne's eyes, surprised. But when she really thought about it, the girl only looked about fifteen or sixteen—she must have been born after the Beastkin War started. It made sense that she didn't know much about the world outside.
"Honestly… there isn't much pleasant to say."
To Kate, those memories were anything but good ones.
"This world has been at war for as long as anyone remembers," she began quietly. "You've seen it yourselves—this planet has only one continent, and all the nations are crammed onto it. So of course there have always been wars. Then came the Pendulum War. It lasted for decades, and finally, the Vayun Government Alliance won."
She shrugged faintly.
"To be honest, we didn't care who was right or wrong, who fought for justice or power. What mattered was that after the war ended, there were four short months of peace—the only peaceful time I can remember. Everyone thought the fighting was finally over. We thought we could finally stop living under air raid sirens, stop running in the middle of the night. Those few months… they felt like a miracle."
She sighed. Back then, she had been just a child—too young to understand what peace meant, only that she could finally sit at her desk without hiding under it, finally sleep without being dragged out of bed by explosions. For little Kate, just living a calm, ordinary life had been happiness enough.
But then—
"The Beastkin invasion destroyed everything. Humanity couldn't stop them. After decades of war, our nations were exhausted, and the Beastkin were prepared. Nobody ever imagined another species had been waiting for us beneath our feet…"
"Why'd they come out then?" Anne tilted her head curiously.
"If they'd always been underground, why decide to come up to the surface?"
"No one knows," Kate said with a shake of her head. It was one of the world's great mysteries.
"There are all kinds of theories. Some say the Beastkin had always lived beneath us, but feared humanity's strength. Only after the Pendulum War, when they saw humans destroying each other, did they decide to strike. Maybe they thought it was their time to take the surface world. Most people used to laugh at such tales…"
"That's not unusual," Duanmu Huai said casually from the front. "Humans have always invented myths about things they don't understand."
Indeed, in his own world there were legends about subterranean civilizations, atmospheric life forms, even Journeys to the Center of the Earth. "Underground people" were basically a pulp magazine cliché.
"Ugh… it's kind of creepy, though," Anne said, hugging her arms. "Just thinking about something living beneath us all this time…"
"I think it's wonderful," Phyllin said calmly. "A chance to see a different world."
"Huh? You'd actually want to go?" Anne asked.
"If I don't have to walk, sure."
Phyllin's eyes drifted toward Duanmu Huai. He sighed.
"Quit complaining. Be glad the tunnels are wide enough for us to walk through."
Honestly, he was just relieved he hadn't gotten stuck.
"Eeeek!!!"
Suddenly, a shriek echoed behind them.
"What's wrong, Lorena?"
Everyone turned. Lorena stood pale and trembling, pointing at a squirming shadow farther down the tunnel.
"Th-that thing! What is that?!"
"Hm?"
Duanmu Huai swung his shoulder lamp toward it—and saw a massive worm nearly three meters long crawling slowly through the passage. It resembled a caterpillar with thick rocklike plating across its back.
Creepy, but slow. Even when Duanmu Huai's light fell directly on it, it didn't react, simply inching forward.
"Oh—don't worry, that's just a burrow worm," Kate explained quickly.
"It looks scary, but it's harmless. It eats minerals and digs tunnels underground. Usually sluggish, no threat to anyone, but…"
Her eyes darted around warily.
"…wanderers who've lived underground say that where burrow worms appear, Beastkin are usually nearby."
"That's convenient," Duanmu Huai said, flexing his shoulders. "Guess it's time for a little warm-up."
They'd been walking too long without a fight; a quick extermination would be a good stretch.
"I'll do my best to protect everyone, too," Kate added, raising her rifle.
Honestly, she still didn't understand why these super-soldiers were traveling with a bunch of girls who looked more like nobles or scholars than soldiers. Were they scientists? Medics?
Whatever they were, they didn't look suited for combat. So if danger came, Kate figured she'd have to protect them—after all, compared to these fragile-looking girls, she at least knew how to fight.
They followed the tunnel until it opened into a vast cavern. There, a massive underground fortress blocked their way—its walls carved with ornate symbols and lined with burning torches.
Clearly artificial.
And the Beastkin patrolling the battlements made it even clearer.
"Well then," Duanmu Huai said, turning back to his team, "time for some exercise. Any stragglers are yours to clean up."
He gripped his warhammer. Olgis and Bambi hopped easily onto his shoulders. The next instant, his jump pack flared—boom—and he launched upward like a missile, crashing straight into the fortress wall.
The Beastkin soldiers saw him coming and swung their cannons around—but before they could fire, Bambi pointed a hand toward them. In an instant, hundreds of bats materialized from thin air, swarming the gun crews. Screaming, the Beastkin tumbled from the walls.
Duanmu Huai landed with a crash that shook the ground.
"BOOM!"
The hammer struck, and the battle began.
As the armored warriors clashed atop the walls, other Beastkin noticed the girls below. Several charged forward, guns blazing.
"Watch out!!"
Kate dove behind cover and shouted a warning—only to realize, to her horror, that the girls weren't even taking cover.
Had they frozen in fear?!
No.
Phyllin exhaled softly. A gust of icy wind swept past Kate, and suddenly, walls of solid ice rose from the ground, intercepting the hail of bullets.
What—? Ice walls? From where—?!
Before she could process it, Anne flipped open a spellbook at her waist and swung her arm. Gale-force winds roared forth, snatching several Beastkin off their feet and hurling them headfirst into the stalactites. Their skulls burst like melons.
Kate stared, speechless, mind blank.
And it still wasn't over.
More Beastkin dropped from a nearby ledge, roaring as they lunged. The robed girl—Ranni—rose gracefully into the air, her body curling as she summoned a cold, luminous crescent moon.
"BOOM!"
The arc of moonlight shattered on impact, blasting the Beastkin back. Before they could recover, Ranni raised her staff—and a storm of meteors rained down, obliterating them completely.
Am I dreaming?
Kate could barely think, staring in shock.
Then—another explosion.
"KRAAANG!"
Phyllin's ice wall shattered, and a berserker female Beastkin charged straight for them, roaring.
Not good!
Kate snapped back to herself, firing wildly, but her bullets barely scratched it. Just then, a small figure in a white robe dashed forward—Lorena, holding a glowing holy tome.
She leapt high, chanting:
"Spirit of wrath, in the name of the Divine, I shall purify your fury—rest in eternal peace!"
Then she smacked the berserker across the face with the book.
The creature flew backward, slammed into the ground, and didn't move again.
"…"
Kate stood frozen, completely speechless.
Was she… dreaming?
(End of Chapter)