Chapter 43:

Underground Adventure!

Momma Isekai: The Doomed Moms Deserve Routes Too!


One hour in.

Things were not going the way Ravela envisioned.

“Another living slime!? Seriously?! It’s the twentieth one!”

But I was having a great time.

“Have at thee,” I yelled, cutting the slime in half.

Split, it lost its form and turned into a sticky puddle.

“Again?” Ravela said, a step behind me. “How are you killing these things in one stroke?”

I turned, brought Ravela close, almost hugging her, and stabbed the slime that was rising a few steps behind her.

“Call it the instincts of an alchemist,” I said.

Ravela let out an audible breath and I looked down at her.

“It’s okay. You can say I’m amazing.”

She sighed and then parted from me. “I’ll tell you how amazing you are when we’re out of here.”

Truth was, I was killing slimes in one strike because they had this cluster of mana in their bodies. Damaging the cluster essentially killed the slime, just like in certain stories.

Mana Vision on, I looked around and confirmed there were no more slimes. 

“Okay, I don’t even want to try going further than this with how often we’re being attacked now,” Ravela said, walking over to a mound illuminated by an old lamppost sitting on top of a peculiar rock formation. 

With Mana Vision, I spotted one of many mana plumes. I went to Ravela, took her hand—

“Hey, I don’t want to do any lovey-dovey stuff when we’re being surrounded by slimes.”

—and moved her over to where the mana plume was.

“Can you please help me search here?” I asked.

“Why here and not there?”

“I think there might be something more interesting here.”

Ravela sighed. “Alchemist instinct?”

I grinned with my eyes. “Yes. Please help me.”

“Okay, I’ll look. Can you please keep an eye out?” Ravela started digging through the trash carefully. “We’re being attacked like crazy, but you’re even crazier with how good at killing those slimes you are.”

“It must be beginner’s luck… That or one of my test compounds gave me anti-slime properties.”

“If you ever figure out which one did it, please give me a dose.”

I looked around and confirmed no approaching mana signatures. “So, what sort of stuff do you tend to look for when you’re down here?”

“Metal with those mana pathways like what your sword has. That sort of stuff is more valuable, as you can imagine.”

“Do you try to sneak it through the lines?”

“Sometimes. The bureaucrats sometimes aren’t very good at discerning good metal covered in mud and grime from scrap metal covered in mud and grime. So, if you get lucky with the staff rotation, you can leave them with the junk and take the actual good stuff. The nobility thinks that the best metal has to be big, but you get the small chunks and someone like Meredi can work miracles with it.”

“So, we’re exploiting the lack of expertise that the nobility has.”

Ravela chuckled. “Helps that the guild isn’t in a hurry to correct their misunderstanding… The most noble, if you were to ask me, is the one who works as a merchant. They’re the ones really winning in the game of life.”

“Oh, just caught a glimpse of an approaching slime.”

Ravela chuckled. “I trust you. You’ve earned it.”

I winked at her, ran toward the approaching slime, and in one stroke, slayed it. Then, after making sure it was the only one, I walked back to Ravela.

“You’re really pulling junk out,” I said, inspecting a weird pipe.

“It’s just so weird…”

“What? The pipe?”

“No. One usually comes across a slime. But this? It’s like they’re coming directly to us…”
Ravela shot me a skeptical look.

“Did you spray some slime attractor on yourself this morning or something?”

“What? No, I don’t have any of that—hmm, actually…”

Ravela’s eyes widened, and her voice deepened. “Timaeus. Did you spray a slime attractor onto yourself?”

“No, no. I don’t have any of that… but maybe… something else is attracting them?”

The first thing that came to mind was the awesome source of mana in my satchel, but I wasn’t going to tell her that.

“I have a lot of new compounds. One might be a slime attractor,” I suggested.

“Yeah, but don’t you seal those real nice and tight to keep them from activating or whatever?”

“Ahh, you know my ways,” I said with a smirk.

“I listen to you sometimes.”

I savored the moment. “You don’t need to say that, but I’m so happy that you did.”

“Yeah, yeah—oh, whoa!”

I crouched down beside her. “Did you find something cool!?”

In her gloved hand was a dented disc of metal, oddly shaped—like it had once been part of a larger mechanism. Despite the grime and corrosion, it was clearly touched by human hands. And embedded near one end, almost like an eye in a warped face, was a small mana crystal—green and cloudy. The crystal was the source of the mana plume.

Ravela turned the thing in her hand, brushing more grime off it with a scrap of cloth. “How did you even know to look here? Actually striking treasure just like that?”

I shrugged. “Just got a tingle on my skin.”

“Like with Old Man Otlan’s ingredients, huh? I’m guessing you’ve taken to that compound?”

“It hasn’t failed me yet, and after today? I might never stop using it.”

She stuffed the metal into her pack, her mood visibly lifted. “Alright, Tingles… Can you do that again?”

I confirmed more plumes. “Definitely.”

“And how certain are you that you can keep killing slimes in one strike?”

“I’m a slime-killing machine right now,” I said, stepping to the side and stabbing the slime that had been creeping up on us. “See? I’ve got slime sense because of my tingles.”

“My plan was to get lucky and find something good after a few hours of searching, but now?” She patted her backpack. “We’ve already got something really good, and I wasn’t even searching that long.”

“My backpack and pockets are still empty.”

“Yeah. I know, that’s why I’m talking this through… See, we need to ultimately go in that direction,” she said, pointing at the blue light of a lantern in the distance. “My plan was to search a lit area and then head over there, but if you can find us the good stuff and save us the effort…”

“Yeah. Let’s do it. We can work our way to where you want to go, and we can pick up stuff along the way. Sounds good to me.”

Glee flashed across Ravela’s eyes before she became stoic again. “Okay, but if we’re going to be stopping to search, we’re probably going to keep seeing slimes. So you have to tell me when you’re tired. As soon as you say the word, we walk straight to the destination. We already found something amazing. We don’t need to be greedy.”

I stood at attention and saluted her. “Yes ma’am! Thank you for your concern, ma’am!”

Ravela nodded with a chuckle and set off at a steady pace. I followed behind her, watching the way her backpack shifted—metal clinked faintly inside.

“You have more than just treasure?”

“Of course,” she said without turning. “I saw a few good pieces of metal while digging. Couldn’t leave ‘em. All of its stuff that people like Meredi could work with.”

I scanned the mounds as I followed her. The level of technology wasn’t anything I could say was higher than what was in the city. I was hoping to see something like electronics, but no, it was all simple mechanical devices, if anything.

We settled into a rhythm—me directing her to the glowing plumes, her digging with expert hands while I stood guard, and us having chill celebrations over the stuff we found. And throughout it all, the slimes kept coming.

“Alright, so you’re definitely freaky,” Ravela said after I’d downed another pair in quick succession. “I’m pretty sure we’re over fifty now… You’re the best slime killer in the city now.”

“And to think,” I said, “I just had to repeatedly drug myself.”

Ravela stifled a laugh. “Right. Thanks for your service.”

“Order me, and I would do it all again.”

She slapped my shoulder. “Stop that. Take care of yourself, dummy.” She shifted her hair to the side and averted her gaze. “Don’t hurt yourself for this hag.”

“This mature, older, beautiful woman probably knows what she’s doing. I choose to keep trusting her.”

Ravela rolled her eyes. “That’s not fair. Come on. Let’s keep moving.”

***

We reached a strange, flatter clearing between two half-collapsed structures poking out of junk mounds. Illuminating the structures revealed stonework that made me think of castle walls.

There were at least five visible mana plumes, all clustered close together here in this flatter clearing.

“Whoa,” I murmured, letting my Mana Vision adjust.

Ravela nodded. “Yeah, I think this spot’s weird too,” she said, kicking loose some of the packed-down junk. “You tingling or what?”

“Crazy tingles. I really want to see what’s under our feet.”

Ravela sighed and pulled a collapsible shovel from the straps of her backpack. “Alrighty then. Keep an eye out. Should be easier for you to see any slimes coming our way. Can you tell how deep it is?”

“No… But all the spots we dug up were roughly the same depth down, which implies...”

“Ahh, you might not be able to tingle if it’s too far down. Gotcha.” Ravela drove the shovel into the junk. “That’s a little more exciting.”

“The allure of treasure’s got you all worked up,” I teased.

“No kidding. Didn’t think we’d pull this much this fast. And now you’re telling me there’s something good here?”

Twenty minutes of shoveling and slime slaying later, her shovel hit something solid with a crisp clang.

“Give me a minute, Tim!” she said, quickly shoveling more junk away.

“There aren’t any slimes in sight. Take your time.”

I stepped closer, eyes narrowing. The glow of the mana was sharper now, leaking through faint seams in what I now realized was a mass of shiny metal.

Ravela wiped her brow, crouched, and began clearing more of the debris, uncovering more of this flat surface.

She tapped a knuckle against it. “This… is huge. I think we’re standing on top of it.”

“From the way my fingers are tingling,” I said, crouching to brush aside more grime. “There is definitely something leaking mana behind this sheet… Or is it a sheet?”

Halfway buried in dust and filth, was a thin horizontal strip of black glass with a dirt-and-grime-encrusted keypad beneath it. An electronic device, just like the ones you’d see on a safe. I found something else when I shifted more trash out of the way—that handle wheel vaults tended to have.

Ravela stepped back, eyes wide. “This is… Holy shit, we found a vault. You know, from the stories. And it’s made of miracle metal.”

“So you all have vaults,” I muttered, unable to turn the wheel. I tapped the keypad. “I don’t think we’re getting in here through traditional methods.”

“Of course not,” she groaned. “If you find a vault, you need to pray you get lucky enough to find it open already.”

She looked down at it with a mournful gaze. “It might even stretch deeper than we think. There could be, like, floors of miracle metal all the way down.”

“Okay, well, that’s a bit of an exaggeration. It’s a vault, not a bunker… ehh, you could probably fit a bedroom in there.”

“Okay, then we agree. We can’t move this.” She kicked the surface. “All it’s good for is taunting us.”

I stayed crouched, hand already on my satchel. “Don’t lose hope so quickly.”

I pulled out a small vial—a translucent liquid with a murky, reddish tint—and uncorked it.

“Tim, what is that?”

“A compound derived from Gloomspawn fluids,” I said. “One of my newer variants. I’ve been working on amplifying its miracle metal-degrading properties with some creative alchemy.”

Ravela blinked. “Wait, really? That stuff eats miracle metal?”

“Yeah, remember my project with Meredi? We were making anti-gloomspawn coatings because gloomspawn fluids damaged miracle weapons with repeated exposure. I just went in the other direction and made the fluids more reactive.”

“Just like that? But Meredi told me her project with you was progressing slowly.”

I poured the liquid on the cleanest spot. “Yeah. Making a compound even better at what it’s already doing is easy.”

The fluid spread like oil and then began to sizzle.

“Fighting against a compound through investigation of its inherent properties is harder. Alchemy, too, is an art that indulges in high-energy and volatile reactions. It lends itself well to destruction. That’s why making the compound more effective was easier.”

White smoke curled upward, accompanied by the sound of soft bubbling as the alchemical reaction ate away at the surface. 

“I don’t have much of it,” I warned. “It’s not an endless miracle compound. But it should make a hole.”

“Hey, I’m not complaining. I’m just shocked you had it in the first place, and even more shocked that it’s working.”

“Yeah… What can I say. I have ambitions. If I want to reach them, then I need every advantage I can create for myself.”

She blinked, staring at the sizzling metal. Then she hugged herself. “You’re unbelievable… I really can’t believe it,” she said with a gulp.

We had a fist-sized hole a minute later. It was pitch-black inside, but I angled my lantern and focused the light into a beam and peered in while Ravela leaned over my shoulder.

“Looks kinda empty,” she muttered.

“Yeah,” I said. I could make out what looked like safety deposit boxes—how nostalgic. A few were opened, too. “I don’t think we need to give up just yet.”

I pulled a long length of rope from my pack, tying a palm-sized weight to the end. Then I coated the weight with a super-sticky inactive adhesive, and heated it up with a match to activate it.

Ravela raised a brow. “We’re going to fish for treasure?”

“Yep. Let’s see what comes up.”

I lowered the rope, guiding the weight through the hole with delicate movements.

“Okay, I’m pretty sure it's touched the bottom.”

“What happens if it sticks to the floor of the vault?”

“That’s why I’m being careful, Rav. The bottom of the weight wasn’t coated.”

I moved it around, trying to get a swing like a pendulum.

“The adhesive—there’s about one second where it can still unstick easily with a good tug. I just have to make sure I pull as soon as I think it’s on a wall.”

“But we’re standing pretty close to the center of this thing, I think.”

“Yup. That’s why it should be okay… There’s a lot of weight on it now,” I said, reeling it back in. “Don’t touch it. I don’t want the stuff getting stuck to you.”

“Yes, sir,” Ravela said with a chuckle.

Out came a golden chain—delicate, intricate, and absurdly luxurious. Looped with tiny gems and shaped links, it looked like something meant to drape across the bare back of someone very rich at a red carpet event. Alongside it, stuck to patches of adhesive or tangled up, came several rings and a couple of gold coins that gleamed even in the weak lantern light.

Ravela gasped. “Mage Gold. This has to be Mage Gold.”

“That’s a thing?”

“It’s the thing. Mana-conductive gold. Rare. Crazy valuable. Hundreds of times more valuable than our shitty coins. Almost impossible to find in chunks like this!”

“Guess it fell out of a box.”

She was still staring at the chain. “Can you keep fishing?”

I cut the weight from the rope and dropped it into a pouch. “Can’t.”

Her shoulders slumped.

“This adhesive is one I only recently revived. I only had the one vial,” I said. “And we can’t reuse it because the adhesive hardens as it cools. We can’t pull the treasure from it for that reason too. We have to use a dissolver that I don’t have. Heh, I was actually planning to make dissolver tomorrow.”

Ravela groaned. “So you can’t fish out more?”

“Nope. Sorry. Didn’t think we’d be fishing today. We got really lucky that I put it in my satchel in the first place.”

She stared at the hole. “Can you use more of the gloom stuff?”

“It’s a new compound, Rav. That was all I had.”

She stared at the vault for a long moment—furrowed brow, and a quiet longing in her posture.

“I hate how much I want to break this open,” she muttered.

I knocked on the vault. “What are the odds we can find this again?”

“If we’re lucky, and come back first thing tomorrow,” she trailed off, sighing. “Maybe. If we get lucky, we can get back here before the trash shifts again.”

I nodded, trying not to let the disappointment sink too deep. I’d taken something extraordinary—but left behind who-knows-what. If there was an overpowered weapon in there…

And then a sound came up from below.

A soft vibration rolled beneath our feet—so subtle I wasn’t sure I felt it at first. Then came a new sound—the groan of metal under strain, the hiss of shifting debris. Several feet away, junk rose.

With a screeching slide of metal and a sickening slop, the mounds of trash slid down a towering mass of rusted parts and plates of scrap, shrinking the further they slid. The mounds had added to that thing--the colossal slime.

Easily the size of a small house, the slime continued stretching upward, pulling with it junk from beneath the surface and further displacing the surrounding junk. We had to be careful too—the first wave of junk came up to our toes like it was water.

“Hey, Rav… What are the odds that all of this junk sits on colonies of slimes?”

She replied with a dry, hopeless, “Haha.”

The slime still had exposed patches, amidst the twisted beams and fragmented metal. I activated Mana Vision and spotted the core. It was more vibrant than the others, and definitely bigger.

“You know, Tim,” she said, eyes stuck on the rising mass. “When you’re down here, you have to stay calm when something goes wrong. It’s how you give yourself the best shot at reacting and surviving.” Ravela gulped. “But… I’m not really sure how to get out of this one.”

She turned to me with the smile that only people who were so totally overwhelmed and in shock could muster.

“Do you think we can outrun it?” she asked.

I looked at the slime and let out a breath. “I think all it takes is for that thing to decide it wants to reach us and we’re done. We’re actually really lucky we stood still.” I stuck my hand into my bag. “Maybe that’s why it’s taking its time emerging… Heck, we got lucky it rose there and not directly below us.”

Ravela tapped her boot against the vault. “Maybe this vault saved us.”

“Yeah…”

I pulled out the drill gem and grinned.

“But in times like this, you’ve got to put your faith in the divine’s navel and pray for a Hail Mary!!”

“Huh? And what is that!?”

I jammed the crystal into the Merry Edge’s slot, and when it didn’t really fit, I twisted it, drilling the gem further into the metal.

“It’s a hope and a prayer,” I replied as the circuits on the Merry Edge lit up.

A low rumble came from the slime. The glow of the circuits intensified.

And then, accompanied by a gust-like sound, vibrant red and white flames spilled from the weapon’s edges.

“Yes!” I cheered. “That’s encouraging!”

“Timaeus, what are you going to do—”

“Hope, Rav! I’m going to hope!”

A vision of what I wanted in mind, I stared right at the glowing core, and swung.

“Come on, give me a Sword Beam!”

The flames of my sword roared. My stroke as a guide, they lashed out and flew straight toward the core, so many meters above us.

The subterranean world flashed red for the first time in centuries as the fire’s vicious roar reached for the enemy.

Slime sizzled, shards of molten metal rained down, hot air shoved us back across the slick vault surface, and junk was forcefully parted by a confluence of forces.

“Whoa,” I said.

“Whoa,” Ravela echoed.

The giant slime was no more.

The mounds of trash directly behind it were no more.

There was just open air, and unobstructed darkness ahead of us.

The Merry Edge—it didn’t release a beam. It released utter annihilation in the form of a slash-shaped wave that traveled through and past the slime, melting so much junk that a burning valley had been formed in its wake.

I held the Merry Edge in front of me and looked at it in total awe, as if it were god sent down from heaven above.

“Ho. Ly. Shit.”

My mouth hung open for a few seconds.

“I’m overpowered.”

Ravela walked up to me, almost as awestruck as I was.

“How in god’s name did you do that?” she asked, hesitant to get closer to the flame-leaking blade.

I turned the Merry Edge slightly and showed her the gem I jammed in. “Powered it up with this—“

“And where did you get that?”

I blinked. “I found it over there in a pile of trash.”

She raised a brow and recoiled. “You just found it?”

“Yeah. It made my fingers all tingly.” I put on a mildly impressed face and nodded at the sword. “Evidently, I can see why.”

“Yeah, no kidding,” she replied, trying to look at the sword from different angles. “So, did we get lucky? Is the slime dead?”

I looked at the scene of carnage. The fires were all giving off mana, but even so, I couldn’t see anything that looked like the mana profile of a slime.

“Yeah. I think it is… I really hope we didn’t just incinerate anyone with that.”

“Ahh, there was probably no one out here. You’re fine, you’re fine… But this sword!”

Ravela was giddy, bouncing on her heels. “Can I try? I’ve never held something so powerful. Is that okay?”

 “That look in your eye is a little scary… But I love it. Yes, here you go.”

Ravela received the sword with the respect it deserved, looking at it like she was a squire and it was the sword that symbolized her rise into knighthood.

She looked at me with happy eyes, the flames radiating like fireflies illuminating her. “What do I do, Tim?”

“Oh… Well, I guess it just works with your imagination… maybe?”

Ravela grimaced. “Oh, this is sort of hot.”

“Just imagine doing what I did and try swinging the sword—”

“Oww, Tim! Take the sword!” Ravela yelled, shoving the sword back into my grip. “It’s hot, Tim!”

“And why did you hand it back to me?” I tilted my head. “Oh. It is hot… But I think it’s going down again.”

“Really?” Ravela asked, looking offended. She poked the sword and scoffed. “It really is cooling down… How? Why?”

I started unscrewing the gem. “Maybe it’s just the way it works, like maybe trying to do another slash causes it to heat up.”

“I’ve never heard of a weapon that’s responsive to its wielder's desire to attack.”

I shrugged. “Ancient world tech, right? We should ask Meredi about it.”

“Maybe,” Ravela replied, still glaring at the sword.

“We can think about it later. For now, we should probably get back to getting out of here. If slimes are the things shifting the trashscape down here, then we’ve got to assume another big one could show up.”

Ravela snapped back to attention all at once. “Right!”  All smiles, she grabbed me by the wrist. “Follow me!”