After handing over all the responsibilities within the cave to Kakashi, Tsunade and Shizune began their journey heading northeast.

Tsunade brought along the three brains in jars, as well as the devices that were paired with the metal cylinders. Shizune couldn't help but shudder as she carefully packed the containers. Even after all this time, I can't get used to the sight...

Tsunade had extracted a large amount of green liquid from the Mi-Go's body, enough to sustain the three brains for two months. In other words, it would take at least two months before they could return.

As they traveled, the landscape changed around them. Dense forests gave way to craggy mountains, which eventually softened into coastal plains. Shizune's curiosity grew with each passing day.

She then couldn't contain her questions any longer. "Tsunade-sama, where exactly are we headed?"

Tsunade's pace didn't slow as she answered. "An island, Shizune. One that doesn't appear on any maps."

"A hidden island?"

"It's a true lawless land, a paradise for the rich," Tsunade explained. "Imagine a place where money is the only law, where the worst of human nature is on full display."

As they continued their journey, she elaborated on the island's nature. Its most famous feature was the ninja fighting arena, where wealthy individuals from different nations had their personally raised ninjas battle each other. The victor could claim the opponent's ninja.

"On this island, even ninjas with highly coveted bloodline limits are mere commodities. Beyond that, the island offered a variety of extreme luxuries, such as exclusive entertainment venues, a black market, and underground auctions of illicit goods."

Listening to Tsunade's description, Shizune found it all hard to believe and asked, "If it's such an evil place, why hasn't any nation taken action against it?"

Tsunade smiled slightly and explained, "You're still too young, Shizune. You think too simply."

"The people there are either wealthy or powerful, controlling vast amounts of wealth and ninja resources."

"If one nation were to crack down on the island, those wealthy individuals would flee with their money and ninjas to other nations, which would be a massive loss for the country trying to enforce the crackdown."

Shizune began to understand. The relationship between the Five Great Nations was like two sides of a balance, and the wealthy individuals were like weights shifting between the two sides. No nation wanted to push those weights to the opposing side, so they turned a blind eye to the island's existence.

Shinobi politics is far more complex than I thought, Shizune realized.

"But what does this have to do with the person we're looking for?" Shizune asked, still puzzled by their true purpose.

"Because that person is a regular visitor to that place. If we offer the right bait, maybe the fish will bite."

"I've already set the bait; let's hope he takes it," Tsunade said calmly.

---

Meanwhile, in a cool cave laboratory, a figure wearing a black robe with red clouds was conducting an experiment.

He placed a small piece of pink flesh into a container, then used a dropper to drip a few drops of thick green liquid onto it, observing the reaction through a microscope.

The green liquid immediately adhered to the pink flesh and gradually began to transform into the same pink color. This new pink substance slowly devoured the original pink flesh, eventually replacing it and then reverting to its original green color.

"Wonderful!" he shouted in excitement. "Fascinating... The Shoggoth cells adapt so quickly, so perfectly..."

Under the microscope, the Shoggoth cells easily consumed human flesh and actively mimicked human cells. If it can mimic human cells so flawlessly, then perhaps... a perfect, shapeshifting body?

Unfortunately, this was only a theoretical idea for now, as the cells were difficult to control. While genjutsu could influence the Shoggoth, it would often go berserk and uncontrollably devour organic matter once the genjutsu ended.

Ever since he received samples of the Ancients and Shoggoth from Pain, he had conducted numerous experiments. After careful study, he found himself far more fascinated by the Shoggoth than the Ancients.

As creations of the Ancients, the Shoggoth's biological adaptability had already surpassed that of its creators. It was no surprise that the Shoggoth had rebelled against the Ancients—after all, no species would willingly submit to a weaker existence.

However, the amount of Shoggoth Pain had given him was quite limited, insufficient for extensive experiments. Fortunately, the Shoggoth's adaptability was incredibly high, being composed of protoplasm—the substance that could give rise to an entire cell.

Because of this, the Shoggoth had the ability to morph and adapt to its environment. As long as it had enough energy, it could continue to differentiate and generate different cells.

So he spent a great deal of time cultivating a significant number of Shoggoth cells.

Now, in front of him, three liquid tanks were almost entirely filled with Shoggoth cells—Shoggoth forms.

These shiny black masses continuously twisted into unimaginable shapes in the tanks. Each transformation would have been considered a miracle for other living beings, but for the Shoggoth, it was as natural as eating or drinking.

He gazed at the writhing masses, mesmerized. Such beauty in chaos. Such potential...

Though he found the Shoggoth incredibly fascinating, he was also interested in the Ancients. If their unique body structures could be applied to ninjas, it would dramatically increase a ninja's combat capabilities.

This text was taken from Royal Road. Help the author by reading the original version there.

Creating his own amphibious ninjas capable of operating on land, in the air, and underwater would be no problem.

But he couldn't conduct those experiments just yet. He was still within the Akatsuki organization, and he couldn't reveal his ambitions too soon. Though Akatsuki had given him great freedom in his experiments, even reducing his and Sasori's missions to allow more time for research, it was all in exchange for his future cooperation in modifying White Zetsu after capturing pure-blooded Deep Ones.

It was a transaction, an investment. However, if Akatsuki discovered his ulterior motives before that, they wouldn't hesitate to eliminate him.

Let them think they control me. In the end, I'll surpass them all.

So for now, he had to tread carefully, though he still dared to make small moves that weren't too out of line.

In the cave, a reticulated python slithered toward him, hissing softly. He extended his hand and allowed the snake to coil around his arm. From the snake's open mouth, he retrieved a small scroll of paper.

Unfolding the note, he read it with interest. After a moment, he smiled playfully, a soft chuckle echoing in the cave.

"A talking brain, is it?" he mused.

---

After staying in a port city in the Land of Lightning for several days, Tsunade and Shizune were finally ready to head to the isolated island that couldn't be found on any map.

According to Tsunade, she had already contacted the island earlier using a special method, informing them that she intended to auction off an item at the underground auction house there.

As they prepared to depart, Tsunade double-checked their special cargo.

"I've sent word about our 'special item'. With any luck, our target will take the bait."

As for the auction item itself, it was none other than the brain in a jar that Tsunade carried with her.

Even though it had been removed from the body, the brain remained active and capable of thought, and with the right equipment, it could even be provided with vision, speech, and hearing abilities.

This was undoubtedly a rare item, one that would surely be alluring enough to draw that individual to the auction.

And today was the day of the auction.

Tsunade and Shizune made their way to the harbor, boarding an unremarkable boat docked in a quiet corner. The boatman, without a word, rowed them towards the unknown seas.

After over four hours of sailing, they could finally make out the silhouette of an island through the fog ahead.

The island resembled a volcanic crater, with hardly any flat ground. The central feature was a bare, conical mountain, giving the appearance of an uninhabited, desolate island.

"It's... not what I expected," Shizune murmured.

"Appearances can be deceiving, Shizune. Remember that."

The boat slowly sailed through a gap in the mountain's cone, and Shizune then realized that the interior of the mountain was a completely different world.

The inside was a vast hollowed-out space, no less lively than Tanzaku Town.

The place was filled with grand buildings, pavilions, and towers, all luxuriously decorated with beautiful carvings. Colorful lanterns hung everywhere, making it all look impressively breathtaking.

It's like stepping into another world!

"Keep your expression moderate, Shizune. This place may look glamorous, but it's more dangerous than you think."

Shizune nodded.

The people on the streets were well-dressed in lavish clothes or evening gowns with expensive jewelry.

Her simple short kimono made her stand out like a country bumpkin.

At least Tsunade was wearing a necklace with a blue-green crystal around her neck, but Shizune had no jewelry whatsoever.

Their modest attire attracted attention in this extravagant setting, with women dressed as wealthy ladies often covering their mouths with fans, whispering among themselves about Shizune's appearance.

They must have assumed Shizune was Tsunade's maid.

"Everyone's staring at us..." Shizune whispered.

"Let them stare. We're not here to impress anyone."

Walking past the outer streets, Tsunade and Shizune arrived at a plaza.

At the center of the plaza was a circular building, above which a noticeable purple dome-shaped barrier could be seen.

Tsunade pointed to the circular building and said, "That's the Coliseum, where the wealthy watch ninja battles for entertainment."

Then she gestured towards a nearby square building and added, "Next to it is the underground black market and auction house, where we're headed."

"They treat ninja battles as entertainment?"

"What do you think the Chunin Exams are?"

As they passed by the fighting arena, Shizune could hear the frenzied cheers coming from inside.

Being a chunin, Shizune knew that battles between ninjas were no trivial matter—most fights ended in death or serious injury. It sickened her that these rich people treated ninja battles to the death as a form of amusement. The Chunin Exams weren't that brutal, right?

Setting her personal feelings aside, Shizune followed Tsunade to the underground auction house.

Tsunade went to the backstage to deliver the auction item, while Shizune leaned against a corridor wall, quietly waiting.

While she waited, a young girl with long white hair, purple eyes, and wearing a pink dress hurriedly ran past in the corridor.

Why is a child here?

The people who frequented this place were either filthy rich merchants or overweight aristocratic ladies. This pure-looking girl immediately caught her attention.

She watched as the girl disappeared around the stairway corner, heading up to a VIP box on the second floor.

At that moment, Tsunade came out and said to her, "Everything's arranged. Let's take our seats."

They sat in the main hall on the first floor, in the general seating.

It wasn't that Tsunade didn't have the status to be in a VIP box, but the regular seats made it easier to observe which VIP box was bidding on her item.

Given the special identity of their target, it was unlikely they would reveal their face, meaning they would probably be in one of the VIP boxes.

"Keep your eyes on the VIP boxes," Tsunade whispered. "Our target won't show their face openly."

"Understood. I'll watch for any unusual movements."

Finally, the auction began.

A wide variety of items were up for bidding, from luxurious goods to human trafficking and even treasures from certain villages.

Most of the items were obtained through illegal means and couldn't be sold at regular auctions, so they were offloaded here.

The attendees, unconcerned that most of the goods were stolen, eagerly bid whatever price they had in mind.

Shizune felt her disgust growing. Is there no limit to human greed? She watched as priceless artifacts and even people were sold to the highest bidder.

"Third box from the left," Shizune whispered, leaning close to Tsunade. "The curtain keeps twitching."

"Good eye. Keep watching."

After a long series of auctions, the final item of the day was brought out.

The auctioneer motioned for the guards to place the item on the table, then spoke in a mysterious tone: "This is a truly magical item."

"Though its outward appearance may not seem like much, it possesses unparalleled wonder and uniqueness in this world. That's why we've chosen to make it the grand finale of today's auction."

"Allow me to present to you," the auctioneer dramatically pulled away the silk cloth covering the item and, in an excited voice, announced its name:

"The talking brain!"

On the table sat the brain in a jar, along with three accompanying devices.

Seeing the realistic human brain inside the metal cylinder, most of the audience let out screams, with some even turning away to vomit.

"Wow!"

"Ugh!"

"What on earth is this? It's hideous!"

Many in the crowd expressed their displeasure, disturbed by the grotesque sight that clashed with their refined tastes.

The auctioneer quickly raised his microphone and said, "Please don't judge this item solely by its unusual appearance."

"For what you're about to witness is a rare but real miracle of the world."

The auctioneer approached the metal cylinder containing the brain and inserted the three devices into slots beneath it.

As the final device clicked into place, something miraculous happened.

A projected human face appeared above a device with a camera! Though the face was expressionless, it was so lifelike that even the wrinkles were clear. The face blinked its eyes.

However, the face wasn't particularly attractive. It was old, with a scruffy beard, giving it a messy appearance.

But this did nothing to diminish the shock that went through the crowd.

"Impossible!" someone gasped.

"It can't be real!" another one cried out.