A girl in a maid’s dress hammered at the door, knuckles drumming like hard rain on wood.

Her hair fell long and glossy, black-and-white skirts framing her like ink on snow; yet her face was all panic, grace wiped clean by urgency.

“Sis Huan, the external passage at East T20’s been breached!”

“Huh? Again? Where’s the Night Trio?”

The purple‑haired girl rose from the couch. Her smile stayed, but tension beaded in her palm like dew turning to glass.

“We haven’t found them. They’re missing.”

“Aya, stay here and take care of our guests. I’ll handle the rest.”

Purple Illusion nodded the maid to the floor and moved toward the door, steps light as a cat in mist.

“Wait. The Mechanical Monster you mentioned… is it the Mechanical Mantis?”

“How do you know about the Mechanical Mantis… don’t tell me you’ve run into one?”

“Mm.”

Yue Liuyi pushed up from the sofa as well, a ripple through still water. “I fought one. They’re dangerous.”

By the mechanical World Tree, Yue Liuyi had crossed blades with a Mechanical Mantis—no threat to her, but death to common folk. Bernadette had almost been cleaved in half.

“Eh? Master, are we going to take down the Mechanical Mantis next?”

“Yeah… but it’s risky. Yin Mu, Teng Ying, Daishi—stay here. I’ll go with LittleSnow to check it out.”

“No. Xiao Yue, you rest here. I’ll go.”

The silver‑haired girl stood with a snap of frost, hand settling on Yue Liuyi’s shoulder, trying to press her back down.

“Hey! LittleSnow, no need. Last time was a fluke. I won’t get skewered again by those things…”

“What—you were stabbed by a Mechanical Mantis?”

Purple Illusion blinked, the showy glaze in her eyes shattering to clean surprise.

“Uh… got careless. We can talk later. Let’s deal with the mantis first! Teng Ying, I’m leaving this place to you.”

“Got it.”

“Ahh… you’re impossible.”

And so Yue Liuyi and LittleSnow followed Purple Illusion toward the door, three silhouettes like swallows cutting through rain.

…

Beneath the Winterwood District, the underways tangled like roots under an old pine. Purple Illusion led them down one of the emergency passages.

Compared to that violet tunnel from before, this one was rough as bare earth—no trim, no flooring, lights dim as dusk, visibility barely five meters.

To match the gloom, Purple Illusion had shed her ornate lolita dress for a white one-piece; her pale bare feet slipped into plain shoes, snow in simple leather.

“You didn’t have to come. This is a Purple Illusion family matter.”

“Maybe. But I think it’s on me too. I can’t just stand by.”

At the end of it all, the World Tree Maiden’s failure had birthed a mechanical World Tree. Yue Liuyi felt the thorn and would pluck it herself.

“Heehee, that so? Looks like you’re not ordinary adventurers… I can feel something strange on you.”

She walked point, but Purple Illusion still watched Yue Liuyi from the corner of her eye, a fox peeking through reeds.

“Of course. I’m the Winterwood’s warden’s younger sister… I’m going to revive Dreamwood Star. Without some skill, how could I?”

“Still chasing that, huh… heehee, fine! I won’t force you then. Don’t mess with my business, and I’ll let you be.”

A small smile curved her lips, like a lantern catching.

“Hmph. Don’t make a favor out of what’s just basic decency. If you meddle with my Xiao Yue, the next mechanical roach is you.”

The silver‑haired girl let her voice go iron‑cold, taking the black‑faced role without flinching.

“Ooh? Such queenly air!”

“Ya! LittleSnow, they’re Mechanical Mantis, not mechanical roaches…”

…

The girls reached their destination.

This was the so‑called outer ring passage, the lowest level of the subway tunnel.

The air felt wet enough to wring, not just from the downpour above. The drainage trench ran close; the water’s rush hissed like snakes in the dark.

Two Mechanical Mantises stood guard, chain‑scythes raised, warning the dark like wolves showing teeth.

Red danger light bled from their eyes, while rubble and twisted rebar littered the ground, a lair left in ruins.

“The collapse you ran into earlier was their doing. They cut through the subway’s outer wall and triggered the cave‑in.”

“Huh? The Mechanical Mantis did that?”

“Of course! They’ve been a headache for me.”

Purple Illusion opened her palm. A black box drifted up behind her like a shadow fish, then floated into her hand. “Since yesterday, they’ve been vandalizing every passage. If I let them keep going, my business empire will crumble in days.”

As if to prove her point, the mantis paused, then raised its scythe again and “worked” the wall.

Szzzt!

Sparks fountained. Under that hot knife, the hard wall shed more chunks like bark shaved from an old tree.

“No! We can’t let them continue. The tunnel might collapse!”

Seeing the wall totter, Yue Liuyi moved to act—but before the Stellar Moon Compass could sing, Dixue had already struck.

She carried no bow, yet silver hair lifted in a wind of mana. She cast a spell built for piercing.

“Break!”

A silver‑white beam lanced clean through a mantis’s head, burning a gaping hole, light hissing like a comet through ice.

But the mantis didn’t fall. It retracted its blade from the wall and pivoted toward Dixue, mechanical joints snarling.

“They don’t die from that. They’ve got multiple cores!”

Purple Illusion reached into the floating box and drew out an azure oval, cold as a pond rock.

“ice in the hole~”

The pale blue arc traced a neat curve through the air, then burst beside the mantis, blooming ice like winter flowers.

Killing frost raced over steel, crusting the mantis in rime; its motions locked for a breath, cogs choking on winter.

“Xiao Yue, the usual!”

“Got it!”

One look from LittleSnow, and Yue Liuyi understood. The Stellar Moon Compass flared in the tunnel, a moon rising in a well.

Szzzt! Szzzt! Szzzt!

Silver beams snapped out, and gravity bent their paths like threads in a loom. The weft crossed and wove into a net of light.

In a single heartbeat, the light‑net needled the mantis shells, punching black smoking holes through their plating, the air smelling of char.

Strong as their build was, they were no match for the World Tree Maiden paired with a princess of the Night Clan. Steel couldn’t stand under moon and night.

Clatter!

Belching black smoke, the two Mechanical Mantises sagged to the floor and lay still, limbs twitching once, then quiet as spent charcoal.