Yoruichi led Nanatsuki into the secret vault of her clan.
"This place is designed like a dungeon labyrinth," Nanatsuki remarked with awe.
Twisting paths branched in every direction. A single misstep could get one hopelessly lost.
"Even before Captain-Commander Yamamoto established the Gotei 13, the Shihoin clan was already known as the Tenshihō Banshōban, the Keepers of Divine Armaments. Because the world knew we stored countless divine weapons, all kinds of thieves used to come for them."
Yoruichi explained as they walked.
"This vault itself is a divine armament—we call it the Labyrinth Treasury. Its layout changes depending on the time of entry and the number of people. Forcing your way in? Even a captain-class Shinigami like me would take several days to navigate it."
"It can trap even captains for days… that's impressive," Nanatsuki praised.
Indeed, that was more than enough to handle most intrusions.
And this was only the first layer of defense. The Onmitsukidō training facility was built right above the vault. If anything went wrong inside, they could respond instantly.
"Didn't we already pass by here earlier? Don't tell me… you're lost?"
Nanatsuki eyed the familiar-looking corridor with doubt.
"...Really? Did we… maybe I took the wrong turn," Yoruichi admitted, scratching her head. "I don't come this way often!"
There were many branches in the labyrinth, each leading to different storage rooms.
They were headed for the room storing Soul King fragments, one Yoruichi had only visited once as a child, led by the previous head. She didn't remember it well.
"Hold on, let me think… I don't quite remember the path…"
Yoruichi rubbed her chin, trying to recall the correct route.
"From the looks of it, the security measures are serious—if even the clan head has trouble finding the path," Nanatsuki laughed.
"What can I say? I wasn't interested in the stuff in that room. I only went once to memorize the route."
"Should be this way… I think?"
She picked the left path out of three, though her tone didn't sound confident.
Fortunately, she still remembered how to avoid the traps inside.
Otherwise, this search would've become far more troublesome.
They followed the left corridor for a while and soon reached a new fork in the road.
"Aha! I remember this now! I know the way!"
Shortly after, they arrived before a door made of Sekkiseki.
Nanatsuki had already seen many such doors in the labyrinth.
They all looked identical on the outside and gave off no hints through spiritual perception.
Some led to traps; others held treasures or powerful items.
Yoruichi opened the Sekkiseki door.
Inside was a vast chamber—easily the size of a basketball court.
Nanatsuki followed her inside and took in the scene.
The walls were covered in dense arrays of Kidō sealing runes.
"Are these all seal formations?"
Nanatsuki recognized some of them, but there were too many to decipher all at once.
"Every one of them is a sealing formation," Yoruichi nodded.
In the center of the room stood a stone table, with all the seals focusing their power toward it.
A rectangular black box rested on the tabletop.
Looking closer, the black wasn't its actual color. It only appeared so because of the densely packed Kidō formations etched all over it.
"The item you wanted, Sensei, is in this box. I'll undo the seal first. If you touch it before that, you'll trigger a backlash."
With that, Yoruichi began chanting the secret unsealing Kidō—a spell passed down only between heads and heirs of the Shihoin clan.
A golden ray of light shot from her fingertip and struck the black box.
At once, the sealing formations on the surrounding walls seemed to come alive, flying toward the center and merging into the box.
Moments later, the walls were completely bare.
The black box had turned white, with a small black dot at its center where the seals had gathered.
"It's open."
Yoruichi stepped forward and lifted the lid.
Inside was the severed leg of a humanoid being.
"This is… the Soul King's right leg."
Nanatsuki's gaze sharpened.
The Shihoin clan's Soul King fragment was a lower leg—intact from calf to foot.
Unlike the Tsunayashiro clan, the Shihoin ancestors hadn't used their fragment for experimentation.
They had simply sealed it away.
Now, Yoruichi was handing it over for Nanatsuki to study—a decision that technically went against her clan's traditions.
"It's in perfect condition. With this, our risk mitigation increases significantly."
Nanatsuki nodded lightly.
"As long as it helps you, Sensei!"
Yoruichi passed the box to him.
Nanatsuki reached in and touched the severed limb.
At that moment, a ripple passed through his shadow.
Dark tendrils slithered forth, snaking into the box and wrapping around the leg's shadow.
After several seconds, the tendrils retracted.
The anomaly in his shadow vanished as if nothing had happened.
The leg still had a shadow—but now it was ordinary, merely cast by light.
Whatever had once lurked within… was gone.
"My shadow abilities have increased quite a bit…"
Nanatsuki noted inwardly.
Though he couldn't yet determine how much, he'd need to test it back at the lab.
"What was that?"
Yoruichi asked in surprise.
"Just absorbing a portion of the shadow. The Soul King's shadow is unique—when these fragments were severed, their 'shadows' were cut away too."
Since he had already explained the Soul King's shadow to Yoruichi, he didn't hide what he'd done.
"I see… then Ukitake's fragment must have a shadow too, right?"
She rubbed her chin, deep in thought.
"But with his body's condition, calling out the Soul King's right arm would cause serious damage."
Nanatsuki shook his head gently.
Ukitake was kind and well-liked.
Their relationship was solid—so Nanatsuki had never set his sights on him.
"But with today's Reishi Shell technology… we could cure Captain Ukitake's lung disease."
That thought suddenly occurred to Nanatsuki.
Now that the ban on Reishi Shell techniques had been lifted, they could cultivate a new shell to replace his damaged lungs.
Ukitake had suffered from congenital lung illness—he'd nearly died from it years ago.
It was only by fusing with Mimihagi, the right arm of the Soul King, that he'd survived.
But after years of fusion, removing Mimihagi now could result in unknown consequences.
After receiving the Soul King's right leg, Nanatsuki parted ways with Yoruichi and returned to the Laboratory training grounds.
He planned to test how his abilities had changed.
Having absorbed the "Shadow of the Soul King" from the severed leg, his shadow powers had increased noticeably.
With a thought, the Zanpakutō at his waist melted like ink and sank into the ground.
His mastery over his Bankai had become so refined that he no longer needed to chant its true name—he could release it at will.
A silent command flickered in his mind. The shadows on the ground rippled, forming five humanoid shadow clones.
Now, he could split off five shadows—each carrying 60% of his full strength!
Before absorbing the leg fragment, he had only been able to create three such shadows.
Not only that, but his shadows could transform into the forms of other Shinigami and wield their Zanpakutō abilities.
It was an extremely versatile power.
With different combinations of shadows and Zanpakutō, Nanatsuki could adapt to nearly any combat scenario.
Back in his fight against Baraggan, he had used the shadows' immunity to Respira—Baraggan's time-based death aura—to defeat him.
Now that he could summon five such shadow clones, his power had once again grown substantially.
"And this isn't even the limit…"
One of the shadows raised its left hand.
Reishi surged toward it—and a spiritual bow condensed in the shadow's palm.
His shadow clones could now use Quincy powers.
"They can wield Quincy abilities too…"
Nanatsuki's eyes narrowed in surprise.
But the more he thought about it, the more it made sense.
If the Shadow of the Soul King could use Quincy powers, so could the shadows born from it.
After all, Quincy power was one facet of the Soul King's might.
The Soul King's essence embodied the traits of Quincy, Hollow, and Shinigami simultaneously.
"Now that I've grasped the power of the Quincy… but I have no one to teach me advanced techniques."
He began to consider whether he should visit the World of the Living to seek out hidden Quincy survivors.
There were plenty of valuable skills in Quincy tradition—he had once witnessed techniques like Ransōtengai and the Sanrei Glove, both remarkable.
There were also specialized tools and moves unique to the pureblood Quincy—only they knew how to craft and teach them.
"But after that last purge… there hasn't been any new intel on Quincy lately."
It wasn't something he could rush.
The remaining Quincy had gone deep into hiding. Finding them wouldn't be easy.
As for the Wandenreich, their base lay far too deep within the Shadow Space.
No other Shinigami could reach it.
Even Nanatsuki's Shadow Step ability could only transport people across surface shadows—not into the depths where the Wandenreich was concealed.
Until he was confident he could defeat Jugram Haschwalth, he had no intention of entering alone.
Haschwalth, the Grandmaster of the Sternritter, was second only to Yhwach.
Even newly appointed captains were no match for him.
Several days later.
Katori-ryu Dojo.
Nanatsuki and Batsu'unsai sat under the eaves, sipping tea.
From time to time, they offered guidance to Azashiro Sōya and Tōsen Kaname, who were training in the courtyard.
"Sōya might graduate early this year too."
Batsu'unsai sighed softly.
Though Sōya was immature and playful, the early graduations of peers like Shiba Isshin had deeply affected him.
He'd actually buckled down and trained seriously for once.
"This kid… honestly, I don't want him graduating too soon."
Nanatsuki chuckled.
"With his personality, he'll probably go wild the moment he's free."
He could tell Sōya lacked the resilience honed through hardship. Deep down, he was still a lighthearted teen who disliked rigorous training.
His current effort was driven more by pride—by the embarrassment of being the last among his peers to graduate.
But Nanatsuki doubted he could keep that fire burning after he left the academy.
"Well, that's Sōya for you. He'll either need time to grow… or he'll have to experience some soul-crushing setbacks. That might change him."
Batsu'unsai gently shook her head.
Back when she led the Eighth Division, she'd seen her fair share of young Shinigami like him.
Not everyone could grow through failure—some were broken by it.
"Your other student from last year, though—he's a steady one."
She continued.
"Tōsen Kaname is incredibly diligent. His past has made him truly treasure this opportunity."
Nanatsuki nodded.
Tōsen had been blind since birth. The suffering he endured in Rukongai couldn't compare to anything Sōya had faced living in the noble districts.
That hardship made him cherish his time training in the dojo.
He practiced day in, day out, never slacking.
In the courtyard, Azashiro Sōya lowered his stance—then suddenly drew his blade.
Flowlight gleamed.
The alloyed training stake was left with a deep gouge.
"Almost half a foot deep!"
Sōya checked the cut and jumped up excitedly.
"Sensei, how was that Flowlight slash?!"
"Not bad. Half a foot's worth of penetration—that's some real power,"
Nanatsuki gave a small nod.
Thrilled to be praised, Sōya placed his hand on the cut in the stake.
Infusing it with Reiatsu, the gouge slowly disappeared.
These alloyed stakes were spiritual tools that could regenerate when imbued with energy—very expensive.
After becoming a captain, Nanatsuki had introduced the Spirit-Converging Pill to all Shinigami under his command.
Thanks to his endorsement, the pill quickly became popular across the Gotei 13.
Sales of Spirit-Converging Pills skyrocketed, giving Nanatsuki much more freedom financially.
The dojo's training gear had been fully upgraded—wooden dummies replaced with high-end spiritual equipment.
"Tōsen! Tomorrow's the finals, and I'm definitely taking the championship!"
Sōya stared at Tōsen with blazing determination.
The Live Blade Tournament finals were happening tomorrow.
Both had made it to the end.
"Hmm."
Tōsen didn't respond much.
After finishing his Suburi practice with the flagfish wooden blade, he immediately returned inside.
He lit incense, placed his Asauchi across his lap, and sat in Zanpakutō Meditation Training.
Tōsen was training his inner world.
His Reiatsu wasn't as strong as Sōya's—mastering his Zanpakutō was his only hope of winning.