Blue Moon Island, Preparations for the Ten Battles!

Following Sasuke's memories of his previous life, the three drifted across the seas beyond the Shinobi World for nearly a month before finally reaching a Phantom Island absent from its maps—Blue Moon Island.

This land had gone undiscovered for centuries in the present world, making it an ideal place to hide.

Thick fog shrouded the waters for several hundred nautical miles around the island. Even navigational compasses failed within it. Had Sasuke not forcibly memorized its spatial coordinates with his Rinnegan in his previous life, they could never have found it.

The island was roughly three times the size of Konoha, with mountains ringing its perimeter. Dense forests covered about eighty percent of its area, and more than a dozen natural inland lakes were scattered throughout, ensuring ample food and water.

Gazing at the blue moonlight overhead, Sasuke's expression turned nostalgic. "Just like when I came here back then..."

Orochimaru's slit-pupiled eyes grew contemplative. "This place is isolated from the world, but it isn't a separate dimension. That means the blue moon is a sensory projection rather than physical reality, much like the principle behind genjutsu. Blue Moon Island must hold some undiscovered truth. Heh heh, perhaps I can make it a research project for my leisure time..."

After a brief rest, the three built several wooden cabins in a forest clearing on Blue Moon Island to serve as their lodgings.

Sasuke asked, "Orochimaru, aren't you going to move the experimental equipment from your various bases here?"

Orochimaru said, "My old equipment is no longer suited to my current techniques. Moving it here would serve no purpose. As for new equipment, I'll find a way to handle that myself. Just focus on your own affairs, Sasuke-kun..."

In the days that followed, Sasuke trained his white cursed seal adaptation every day, and Kabuto naturally became his sparring partner.

At first, Sasuke held back, afraid of hurting Kabuto.

But after receiving Hashirama cells, Kabuto's chakra and physical abilities had improved considerably. Combined with Medical Ninjutsu, ordinary wounds were easily healed.

The dōjutsu Blade Reversal also gave him overwhelming mobility!

Once he got serious, he could actually put some pressure on Sasuke!

That allowed Sasuke to cut loose a little!

On their twenty-seventh day on the island, training was nearing its midpoint.

"Fire Release: Kagutsuchi!"

Boom...!!!

The fireball surging from Sasuke's mouth suddenly stretched skyward in an enormous pillar!

Kabuto was stunned. "That shape transformation!?"

Sasuke said, "My Kagutsuchi can now control not only black flames, but ordinary fire as well!"

Boom...!!

The pillar exploded in the sky, transforming into countless meteor-like flames that rained down over the battlefield!

Kabuto Yakushi exclaimed, "That range!!"

Sasuke said, "Unless you use Blade Reversal to flee the battlefield outright, you won't escape this Meteor Shower!"

Kabuto Yakushi adjusted his glasses and smiled. "Really? I wouldn't be so sure..."

"Blade Reversal!"

Whoosh! A vortex emerged from his right eye, teleporting Sasuke straight to him from a distance!

Blade Reversal, the template for Uchiha Shin's ocular power, allowed transport between marked objects. Not only could the user send himself to a distant location, but he could also pull a distant target to his side!

Yet despite its convenience, Blade Reversal had many weaknesses. Its ocular marks could only be applied through direct contact, were visible, and could be physically erased. In those respects, it fell far short of Kamui and Amenotejikara!

Sasuke said, "That trick again!! I know I removed the marks on my body before bed last night. Did you mark me again without my noticing?"

Kabuto Yakushi smiled. "There are no marks of mine on your body, but I cooked your breakfast this morning!! I tested it—mere stomach acid can't erase the marks!!!"

Boom...!!

Now caught within his own attack's range, Sasuke had no choice but to divert the raining fire. Boom, boom, boom... flames erupted all around them!

He sighed. "Kabuto... you really do have twisted tastes, no matter when!"

Kabuto took it as a compliment instead. "You flatter me, Sasuke-kun..."

But just then, the corners of Sasuke's mouth lifted slightly. "Kabuto, haven't you overlooked something? You marked the food, not me. If you used Blade Reversal, shouldn't you have teleported the remnants of the food out of my body?"

"!!!!"

That startling realization struck Kabuto like a bolt of lightning!

"D-don't tell me you..."

Sasuke said, "That's right. I noticed long ago that you'd tampered with the food, so I secretly threw it up after eating. I never removed the marks on my body!"

Kabuto Yakushi cried, "You...!!!"

"That's what you call being too clever for your own good..."

Whoosh!

"Wood Release: Hidden Shadow Snake Hands!!"

Sasuke thrust out his left hand, and snake hands formed from Wood Release shot from his sleeve, binding Kabuto Yakushi!

Sasuke had developed this technique by modifying Wood Release: Great Forest!

Glug, glug, glug...!

Kabuto exclaimed, "This wood... it's absorbing my chakra!?"

After a moment's hesitation, Kabuto knew he had completely lost the initiative. In a real battle, that would have given Sasuke enough time to kill him three times over.

Watching from the sidelines, Orochimaru was delighted. "Although Sasuke-kun's Wood Release is still limited at this stage, he's already created something new in so little time. Truly impressive..."

Clap, clap, clap!

He walked forward, applauding. "That's enough training for today."

Kabuto Yakushi sighed. "Well... counting today, that makes twenty-seven straight losses for me."

Kabuto was by no means weak now; he was even on par with the members of the Akatsuki. What truly prevented him from serving as a proper opponent was their familiarity with each other. They inevitably held back, and the atmosphere never grew truly serious...

The First Battle was only three days away.

As night fell, Sasuke washed away the day's grime in the lake.

Beneath the moon, Kabuto Yakushi spoke with Orochimaru.

"Lord Orochimaru, the date is approaching. Have you decided on Sasuke-kun's opponent for the First Battle?"

"You should be quite familiar with him. He's currently one of the Akatsuki's full members..."

"Do you mean... could it be..."

"The Jade Maiden of Akatsuki, Sasori of the Red Sands..."

Years ago, while Kabuto had been working as a spy in the Hidden Sand, Sasori had placed a technique on him that controlled his mind. Orochimaru had undone it, but Sasori remained completely unaware of that.

Kabuto adjusted his glasses and smiled. "There's a touch of personal resentment in this choice, isn't there..."

Orochimaru said, "Not entirely. Sasori is very powerful, and Sasuke never met him in his previous life, leaving a blind spot in his intelligence. That makes him an ideal opponent for the First Battle. What interests me even more is that Sasori has always held something back. Even during his admission test for the Akatsuki, when Konan defeated him, he never used the Scroll he keeps as his final trump card. The unknown always arouses my deepest curiosity..."

Kabuto said, "Understood. I'll take care of luring Sasori in. Where shall we arrange the battle?"

Orochimaru gazed at the moon with his slit-pupiled eyes, a faint hint of nostalgia crossing his face.

After a long silence, he slowly said, "Tenchi Bridge."