As I approached the liquid that had dripped onto the iron rod and examined it in response to Hwa-eun’s explanation, I became convinced—this was sulfuric acid.

A colorless, odorless substance that corrodes metal.

Eyes lighting up, I asked about something else.

Only one final ingredient remained now.

“Then... could I possibly get my hands on some saltpeter?”

At that, both Hwa-eun and her grandfather turned to each other with utterly baffled expressions.

As if I had just said something completely absurd.

Seeing their faces, I had a sudden feeling that this might not be easy to obtain.

What the— Is it classified as a strategic material or something? I thought fireworks powder was made and sold all over the Central Plains without much regulation. There was a ridiculous loophole in the counterfeit coin plan that let me slide through, but this is where I hit a wall?

I had gotten through the counterfeiting scheme so smoothly, and now—ironically—I was hitting a wall trying to get saltpeter, which I thought would be simple.

Saltpeter. Potassium nitrate.

Since it’s used to make gunpowder, maybe it’s under government control.

I vaguely remembered from history class that China once restricted saltpeter exports to prevent Joseon’s military from getting stronger.

That’s when Grandfather, with a grave expression, turned to Hwa-eun and said,

“Just as you said a few days ago, So-ryong should probably stay home for a while. Ahem.”

“Huh? Stay home?”

“Yes. Best he not go anywhere for a while.”

Wait, what? I just asked one question and now I’m under house arrest?

Did they suddenly think I was some dangerous person trying to make explosives?

While I was still flustered, Hwa-eun nodded in agreement with her grandfather’s words.

“So-ryong definitely shouldn’t go out for the time being.”

“Indeed. Never thought I’d see the day someone in the Sacheon Tang Clan would ask if we had saltpeter.”

“What’s that supposed to mean?”

Everyone reacted as if my house arrest was the most natural thing in the world.

As I stood there dumbfounded, Mandok Shingun—Grandfather—gave me a frustrated look and asked,

“You little rascal, do you even know where saltpeter is most abundant in all the Central Plains?”

“Nope.”

I mean, if I knew that, would I be asking you to get it for me?

My swift reply prompted a scolding.

“That’s nothing to brag about! Saltpeter is most abundant in northern Mianyang, Sichuan Province!”

“Northern Mianyang, Sichuan...?”

Wait a second. Isn’t that right here?

If it’s the northern part of Mianyang in Sichuan, that’s basically near Tangga Mountain.

Which makes sense, since the river flowing past Tangga Mountain runs right through Mianyang.

That’s why we passed through Mianyang when returning via Geumdo.

As I blinked in realization, Hwa-eun smiled and explained further.

“So-ryong. The Sacheon Tang Clan doesn’t just deal in poisons and medicine. We also profit from the saltpeter mines. What Grandfather meant is that you really don’t know anything about the family, so you should stay home and learn more about it.”

“I—I see.”

So that’s why they put me on house arrest. I basically walked into a noodle shop and asked if they sold dumplings.

Though come to think of it, most noodle shops do sell dumplings on the side. I just didn’t look at the menu and asked blindly.

As the clan’s son-in-law, I didn’t even know what kind of business the family ran. No wonder they were dumbfounded.

Scratching my head under Grandfather’s gaze, I gave an awkward smile.

When in doubt, just smile.

“Ahaha...”

“Ridiculous brat... Alright then, is there anything else you need?”

Even though I’d just revealed my total ignorance of the clan, he didn’t seem particularly angry.

When he asked if I needed anything else, I decided to list what came to mind.

“A few blacksmiths, some poison artisans, saltpeter, and—what was that called again, Hwa-eun? The gallstone from the rock?”

“Seokdamjeong.”

“Ah, right. Seokdamjeong.”

“Just a few blacksmiths, some poison-makers, saltpeter, Seokdamjeong, and some Majeun silver ingots would do. Oh, and I’ll need Ranghyang too. Plus the Hoye kids.”

—Kyuki?

At the mention of needing not just Ranghyang but also the Hoye salamanders, Hwa-eun blinked in surprise.

“The Hoye too? Whatever this is, it’s not dangerous, is it? Those kids still seem pretty untamed.”

She seemed worried—understandably so, since one of them had nearly taken her life once.

But they’d since opened their hearts to me.

I gave a reassuring expression.

“They’ve already opened up to me, so there’s no need to worry too much. When I came back last time, one of them even came up and hugged me.”

“They hugged you?”

Gone was the angelic Hwa-eun who had just looked at me like I was the cutest thing alive. Her brows now shot up into a sharp V.

Hwa-eun’s expression morphed from celestial to demonic in an instant.

They say when a woman becomes a mother, she transforms into someone strong. Our Hwa-eun already had several "children," so maybe that’s why she seemed so powerful.

Just making eye contact is enough to make me break into a cold sweat.

Her look said it all: After all that chaos before, you went and let one hug you without even telling me?

“Uh—no, I didn’t hug them, I mean—they hugged me first...”

As I stumbled over my explanation, Hwa-eun turned to Grandfather and said,

“Grandfather, forget the house. So-ryong needs to be locked up in a storeroom.”

To which Grandfather chuckled heartily and replied,

“Hahaha! Then let’s lock him up in his chambers right away. Tie him down tight to the bed, and you lie next to him and guard him well.”

“Oh! That’s an option— Wait, what?”

Wait a minute, that sounds like a reward.

I thought I was about to be punished, but instead I got... that?

Hwa-eun’s cheeks flushed red, her earlier outrage forgotten for a moment.

***

“They’re really tamed now, Hwa-eun. And for this task, we won’t even need to touch the kids.”

“That lie—this time it’s true, right?”

“Of course!”

“So it is a lie.”

“N-no!”

The Sacheon Tang Clan was said to be full of poison experts, but I didn’t expect them to be masters of verbal traps too.

True to her bloodline, Hwa-eun was just as cunning when it came to laying those conversational snares.

After struggling for quite a while to dodge Hwa-eun’s verbal landmines, I finally managed to get out—only after promising multiple times to handle the Hoyes with the utmost care.

“You have to be careful.”

“Yes, yes.”

“You sound a little half-hearted.”

“Come on, no way.”

With that, I was released and immediately escorted by Mandok Shingun—Grandfather—to one of the Tang Clan’s poison manufacturing facilities, where the clan’s expert poison artisans were waiting.

Unlike the inner hall of Mandokjeon, where I’d once gone to make the antidote Ji-damhwan, this was an external pavilion I was entering for the first time.

It was filled with all kinds of intricate tools made of ceramic.

“You all are to follow So-ryong’s instructions precisely. Not a single step out of place.”

“Yes, Supreme Patriarch.”

“Just give us the word, Lord So-ryong.”

After Grandfather gave his stern warning and took his leave, I stepped forward to address the gathered poison-makers and began by asking if they had the tools I needed.

“First, I’ll need to collect vapor and condense it into droplets.”

I was referring to a distillation apparatus. One of the artisans answered right away.

“Ah, you must mean something like how we boil liquor and collect the steam. Is that it?”

“Yes, exactly that.”

“That’s commonly used when concentrating poisons, so of course we have it. What will you be using it for?”

The first step in making the counterfeit silver was preparing sulfuric acid.

And once sulfuric acid was ready, the next step was synthesizing nitric acid.

I explained what I knew.

Since we had saltpeter, making nitric acid would be relatively simple.

“First, we need to expose the Seokdamjeong to sunlight to intensify it, then dissolve it into the saltpeter. You must pour the Seokdamjeong slowly into the saltpeter bowl. Never the other way around.

The bowl with the saltpeter comes first, and you gradually add the Seokdamjeong into it.

Keep the area well-ventilated. And be very careful.”

“Don’t worry, Lord So-ryong. We’re well aware of the dangers of Seokdamjeong.”

The nitric acid preparation would start by pouring sulfuric acid into saltpeter to make a mixture.

Once the saltpeter dissolves, the next stage is the distillation of nitric acid.

“Next, we’ll heat the mixture and collect the steam that comes out. But do not boil it vigorously—just gentle heating.”

The ideal temperature for nitric acid distillation was around 70–80°C.

After I explained the precautions, the artisan in charge nodded and asked,

“Understood, Lord So-ryong. So, we just need to collect the resulting liquid?”

“No. Once that liquid is ready, we’ll add silver to it. The silver will dissolve, and what I need is that silver-infused solution.”

“In that case, we’ll get started immediately.”

With that, the poison artisans bowed and got to work.

They covered their faces with detox cloths, opened all the windows of the building, lit the furnace, and began arranging the distillation apparatus.

“Please step outside for safety.”

“Of course.”

As I stepped outside, the voices of my curious family members greeted me.

“Heh, heh. Very methodical. I wonder how that turns into silver.”

“I’m curious too, So-ryong.”

“Same here, son-in-law.”

The rumor that I was making something had apparently reached the entire household—even my father-in-law had shown up, his eyes sparkling with curiosity.

But I couldn’t explain it now.

“That would ruin the fun. Come back when it’s complete and see for yourselves.”

“Don’t be like that, son-in-law. Just a little hint.”

“Come on, So-ryong. Give us a sneak peek.”

“No can do.”

At my firm refusal, both my father-in-law and Grandfather Mandok Shingun looked disappointed. But Hwa-eun, clearly thinking she was the exception, smiled sweetly and asked,

“I don’t count, right? So-ryong, you’ll tell me, won’t you?”

She had that confident smile that assumed I’d cave—for her.

I smiled back and answered.

“Nope. Not even you, Hwa-eun.”

“Wait—what? So-ryong? Not even me?”

“If I explain now, it won’t be any fun. Besides, this is something better shown than told.”

It wasn’t because I was still bitter from earlier, definitely not.

Well... maybe a little.

I mean, I didn’t even know the proper chemical equations—explaining this clearly would be a nightmare.

That’s why I said no. Still, Hwa-eun looked truly blindsided that she was excluded, too.

She looked mildly offended.

Sensing the danger, I figured I should get moving—fast.

Escaping the brewing storm, ❀ Nоvеlігht ❀ (Don’t copy, read here) I headed straight for the forge.

At one side of Tangga Mountain, smoke rose steadily into the sky.

Once I arrived, I informed a nearby worker of my arrival, and the forge’s head craftsman came rushing out to greet me.

“Welcome, Lord So-ryong. I am Kwon Gyu-sam of the forge. I’ve heard from the Patriarch. What can we make for you?”

He was a middle-aged man with graying hair and ridiculously muscular arms. I handed him a prepared Majeun ingot and said,

“I’d like you to replicate this exactly. But since it’s supposed to be Dragon Silver, the outside needs to be engraved with those characters.”

“So you’re asking for a standard Dragon Silver replica?”

“No. It should be made of iron, hollowed out inside, and filled with something else. The filling mustn’t rattle, and the total weight has to match real silver.”

At first, Kwon Gyu-sam had assumed I wanted a basic replica, but what I needed was a fake ingot made of iron—same weight, solid appearance.

He nodded as he understood.

“I see what you’re asking. How many shall we prepare?”

“Let’s start light. Ten pieces.”

“Understood. I’ll get on it right away. We’ll make the outer shell from copper and fill the inside with clay.”

“Perfect. Thank you.”

With those two pieces now in motion, it was time for the final prep.

I figured I should give Ranghyang a nice soak in distilled water.

I needed to extract cyanide from his body, after all.

Once all the ingredients were ready, the plan was simple: mix cyanide extracted from Ranghyang into the nitric acid prepared by the poison masters, then dip in the fake silver ingots made by the blacksmiths.

After that, channel electric current through it using the Hoyes.

That’s it—electroplating using cyanide and silver nitrate.

Poison, when used right, is incredibly useful.

In my past life, I’d been so curious whether the cyanide from a millipede like Ranghyang could be used for silver plating, I’d gone all the way to a university chemistry lab to test it.

That was one of my content projects—Silver Plating with Poison.

Now, here I was, using that knowledge in my new life to create an Five Venoms Sect exclusive.

This one’s for you guys—an exclusive poison-content special.

I honestly couldn’t wait to see their faces when they found out the silver was fake.