I run a casino in the immortal realm.

Zhang Biao remained silent for a long time.

Only the faint hum of the spirit lamp remained in the office. Dusk deepened outside the window, the peaks of the Qingyun Sect were dyed a deep purple by the sunset, and the continuous sea of ​​clouds churned with low, surging spiritual energy.

"I'll go."

Zhang Biao stood up, put the spirit stone into his pocket, and did so swiftly without hesitation.

"Zhao Wenyuan is quick-witted and clever, but he's not strong. With me here, no one dares to cause trouble at Tianyuan Casino."

Zheng Yifei nodded: "Su Qingwan will be returning to Sujiafang City in half a month. You will go with her. In the next few days, make sure you understand the information I gave you."

"OK."

Zhang Biao walked to the door, then suddenly turned back: "Where are the gambling equipment? Those things aren't cheap; they need to be reinforced with an array."

"I'll take care of the gambling equipment."

After seeing Zhang Biao off, Zheng Yifei picked up a piece of spiritual paper and began to draw.

He drew playing cards.

Three inches long and two inches wide, he didn't use spades, hearts, diamonds, or clubs, but instead used patterns that the cultivation world could understand: sword, pill, talisman, and cauldron, corresponding to four common images in cultivation. They were highly recognizable and could be remembered without explanation.

J, Q, and K have been replaced with the three spiritual characters "将, 后, 王".

A is reserved.

Use Arabic numerals for numbers.

He also drew the specifications for Pai Gow—made of jade, with a black background and gold patterns, thirty-two tiles, each engraved with a different combination of dots.

The dice have six sides, are made of spirit jade, and are completely transparent, so gamblers will not suspect any trickery.

Finally, there's the roulette wheel, a three-foot-diameter spirit wood disc with thirty-seven slots, numbered from zero to thirty-six, alternating between red and black. The central bearing requires spirit copper balls, and the friction must be extremely low to ensure randomness.

It was already late at night when the four drawings were finished.

The next morning, Zheng Yifei went to Qifeng.

Qifeng is located northeast of Qingyun Sect. The mountain is steep, and the area above the halfway point is shrouded in red smoke all year round. That is the spiritual energy rising from the residual heat of the weapon-refining furnace. From a distance, it looks like an active volcano.

He was looking for Xu Jian, the steward of Qifeng. He had worked with Xu Jian when the General Affairs Department made the fountain pen and printing plate last time, and the two had a meal together and were already quite familiar with each other.

Led by a disciple of Qifeng, he met Xu Jian in a small courtyard.

"Senior Brother Xu."

Xu Jian looked up and saw Zheng Yifei. He threw the file on the ground, stood up, and dusted off his backside.

"Oh, Inspector Zheng, what a rare guest!"

His tone was slightly teasing. He had earned a good processing fee from the last batch of pens and printing plates, so he had a good impression of Zheng Yifei.

"Senior Brother Xu, are you free at noon? Tianxiang Pavilion, my treat."

Xu Jian rubbed the copper dust off his hands: "Tianxiang Pavilion? It's not cheap there."

"It's alright, I have some business to discuss with you."

"That's great."

Tianxiang Pavilion, second floor.

Zheng Yifei didn't order the same expensive dishes as last time, but it wasn't stingy either—four dishes and a soup, plus a pot of spirit wine, the level was just right at "respectful but not obsequious".

Xu Jian wasn't picky about food or drink. He picked up a piece of lingzhi mushroom with his chopsticks and stuffed it into his mouth, asking as he chewed, "So, what are you going to make this time?"

Zheng Yifei laid the four blueprints out on the table one by one.

Xu Jian put down his chopsticks, wiped his hands, and picked up the first card—a design drawing of a playing card.

"What is this?"

"These are called playing cards, a deck of fifty-four, made of thin slices of spirit wood with a spirit lacquer finish, and the key thing is—"

Zheng Yifei pointed to the blueprints: "A shielding array pattern must be engraved on the back of each card."

Xu Jian's eyebrows twitched: "Block what?"

"Divine consciousness".

Xu Jian held the blueprints up to his eyes.

"You want to make this deck of cards so that the suits on the front are not visible under divine sense scanning?"

"right."

Xu Jian put down the blueprints, leaned back in his chair, and his expression changed.

It wasn't that I was embarrassed, it was that I was interested.

"Foundation Establishment stage divine consciousness?"

"All levels above the initial Foundation Establishment stage are blocked."

Xu Jian whistled: "The requirements are quite high."

"How much is a pair?"

Xu Jian counted on his fingers for a while: "Spirit wood base, spirit lacquer, and the inscription of third-order shielding array patterns... a set of fifty-four sheets, about ten spirit stones."

"Make one hundred sets."

He put the playing card diagram aside and picked up the second card—a domino: "What about this one?"

"Made of spirit jade, also engraved with shielding array patterns, thirty-two sheets per set, make ten sets."

Xu Jian picked up the third die and his eyes narrowed when he saw the words "embedded balance array pattern".

"You want to make a perfectly fair dice?"

"Yes. The probability of each face appearing must be strictly equal, with an error of no more than one in a thousand."

Xu Jian put down the blueprints and looked Zheng Yifei up and down.

"Do you know what kind of dice they use in gambling dens outside?"

"I know. There are many types: lead-filled, eccentric, manipulated by array patterns."

"You insist on being fair."

"Fairness itself is the biggest selling point."

Xu Jian clicked his tongue and didn't ask any more questions. He was a craftsman; he would make whatever the customer wanted, and what the customer did with it was none of his business.

The last drawing is a roulette wheel.

Xu Jian watched for the time it takes to drink a cup of tea.

"This is interesting."

He pointed to the structural diagram of the central bearing: "Spirit copper ball bearing, no array interference, purely physical randomness... You've even ruled out the possibility of the bookmaker cheating?"

"The bookmaker doesn't need to cheat."

Zheng Yifei picked up his chopsticks, dipped them in tea, and drew a simple probability distribution diagram on the table: "Thirty-seven grids. A gambler who bets on a grid wins 35 times the stake. It seems fair, but the house has an extra 'zero' digit."

In the long run, the house's advantage is 2.7%. This means that for every 100 spirit stones a gambler bets, the house earns an average net profit of 2.70 spirit stones.

Xu Jian stared at the number, remaining silent for a long time.

"Winning money purely through arithmetic, without cheating or underhanded tactics?"

"right."

"Your brain..."

Xu Jian shook his head, picked up his wine bowl and took a swig: "What a pity, why did he become a tax collector?"

After two bowls of wine, the conversation gradually unfolded.

Zheng Yifei didn't hold back and revealed part of the subsequent business plan to Xu Jian—slot machines, scratch cards, and lottery tickets all require Qifeng's support, and these are long-term, large-volume orders.

What is a slot machine?

"A kind of puppet mechanism that can be deployed in any shop; once these things are deployed..."

Zheng Yifei held up one finger: "You are the exclusive supplier. Deacon Xu Jian of Qifeng Miscellaneous Equipment Shop, the patriarch of the gambling equipment industry in the cultivation world."

Xu Jian was amused by the words "Grandmaster", but after laughing, his expression became more serious.

"Poker, Pai Gow, dice, roulette—is ten days enough?"

More than enough.

Xu Jian folded the four blueprints neatly, put them into his sleeve, stood up, and cupped his hands in greeting: "Two thousand spirit stones, delivery in ten days. Just send someone to pick it up then."

Zheng Yifei took out two thousand spirit stones from his storage bag and made the transaction on the spot.

Xu Jian weighed the storage bag in his hand, then left satisfied, his pace quickening considerably from when he arrived.

Ten days later.

Peak.

Xu Jian placed the four wooden boxes on the table and opened them one by one.

The first box contained one hundred decks of playing cards, neatly stacked in ten piles. The thin slabs of spirit wood were polished smooth as a mirror, with a warm, smooth feel and uniform thickness.

The four-colored patterns of "sword, pill, talisman, and cauldron" on the front are painted with mineral pigments, which are bright but not dazzling. The back is a uniform dark blue background, with third-order shielding array patterns hidden in the dark patterns. The spiritual light is restrained and cannot be noticed unless you look closely.

"I've tried it. My senior uncle, who is in the late Foundation Establishment stage, scanned it three times with his divine sense, but he still couldn't see through it."

Xu Jian crossed his arms, his tone filled with undisguised smugness.

The second box contained dominoes and dice. The jade dominoes were warm to the touch, with a black background and gold patterns, and their quality surpassed even the highest-grade ivory dominoes on Earth. The dice were transparent hexagonal cubes made of jade, which was even more reassuring than those ivory products.

The third box contains the parts for a roulette wheel. Once assembled, it is three feet in diameter and spins smoothly and silently, with the ball bearings moving randomly between the slots.

After Zheng Yifei completed the inspection, he closed the box lid with satisfaction.

"Senior Brother Xu, there's more big work to come."

"Slot machines?"

"Yes, but no rush. Let's wait until the casino is up and running smoothly before making any decisions."

Xu Jian nodded and bowed to see the guest out.

That evening, Zheng Yifei handed the four wooden boxes to Zhang Biao.

"Everything's ready. Head out with Team Leader Su first thing tomorrow morning. Once you get to Sujiafang Market, find Zhao Wenyuan first, give him the letter and the proposal, and then you two split up—he'll handle operations, and you'll handle security. Contact me via telepathy if you have any questions."

Zheng Yifei gave him a teleportation talisman, which Xu Jian had given him.