Five minutes later, Uchiha Dan and Tsunade arrived at the foot of a mountain at tremendous speed. They hurried toward the summit, and before long, they spotted the enormous body of Katsuyu.
"Is that Sage Katsuyu?" Uchiha Dan asked, staring at the gigantic body, which stood five hundred meters tall even while lying down.
"No, that's only a part of Sage Katsuyu!" Tsunade explained. "Sage Katsuyu's main consciousness resides in that part."
"No one has ever seen Sage Katsuyu in its entirety."
"Whoa..." Uchiha Dan exclaimed in amazement, then cast a strange look at Tsunade.
Who was it who'd claimed during a fight that she could summon one-tenth of Sage Katsuyu?
She hadn't even summoned one-tenth of this tiny fraction, had she?
Uchiha Dan had always found it strange.
Sage Katsuyu was a sage, on the same level as the White Snake Sage and Gamamaru.
How could the likes of Manda and Gamabunta compare to her?
Even one-tenth of Sage Katsuyu should have crushed Manda and Gamabunta, yet she'd barely shown anything impressive. It was hardly worthy of a sage.
So it had only been one-tenth of a tiny fraction. That explained everything.
It was a good thing Uchiha Dan knew Sage Katsuyu was gentle. Otherwise, her mountain-sized form would have scared him to death.
After climbing for quite a while, Uchiha Dan finally breathed a sigh of relief. The higher they went, the thinner the corrosive gas became.
By the time they reached the summit, the air was no different from the outside world.
"Hello, Uchiha Dan!" Sage Katsuyu greeted him first in her soft, gentle voice, without a hint of arrogance. "Would you like to learn Senjutsu?"
"Hello, Sage Katsuyu. Can I learn it?" Seeing Sage Katsuyu ask him directly, Uchiha Dan suddenly perked up.
Sage Katsuyu didn't answer. Instead, she swallowed Uchiha Dan whole.
Uchiha Dan didn't panic at all. Once inside Sage Katsuyu, he felt as if he'd entered another world.
The next moment, Natural Energy surged toward his body, washing over him like a torrent.
Uchiha Dan closed his eyes and focused on the sensation. To his astonishment, he found that the Natural Energy was incredibly compatible with him.
Almost without thinking, Uchiha Dan drew a trace of Natural Energy into his body.
As he balanced his physical energy and spiritual energy with that trace of Natural Energy, a tiny amount of Senjutsu Chakra formed inside him.
There was hardly any of it, but the whole process felt completely natural.
This was Uchiha Dan's own talent, not something he'd inherited from Tobirama Senju.
Uchiha Dan was thrilled. He hadn't even known he had this kind of aptitude.
After spitting Uchiha Dan out, Sage Katsuyu nodded in satisfaction. "I can tell you have a great talent for Senjutsu. You're very well suited to learning the Senjutsu of Shikkotsu Forest."
"You lucky jerk!" Hearing Sage Katsuyu's words, Tsunade felt utterly dejected.
Tsunade had no talent for Senjutsu at all. That had always been her greatest regret.
She hadn't been too upset about it before.
After all, Shikkotsu Forest's Senjutsu was the hardest to learn of the Three Great Sage Lands, and the only person she knew who'd mastered it was Hashirama Senju.
But now Uchiha Dan could learn it too.
What made him so special?
Still, she was only venting. Deep down, she was genuinely happy for him.
After all, she'd been the one to suggest to Sage Katsuyu that Uchiha Dan learn Senjutsu. There was no way she could truly be jealous.
All Tsunade could think about now was helping Uchiha Dan gain enough strength to protect himself, so he wouldn't have to face the threat of death again.
Mastering Senjutsu meant he'd finally be able to protect himself. Before long, he'd truly be able to live openly in Konoha.
Hashirama Senju's experience had taught Tsunade that once someone became strong enough, rules couldn't hold them back.
People like that were the ones who created rules for everyone else to follow.
Once Uchiha Dan could make the rules, would anyone in Konoha still dare to cause trouble for him?
And so, after seven years of frustration, Uchiha Dan finally began his training.
Naturally, Tsunade volunteered to be his teacher.
For the next month, Uchiha Dan was reverse-summoned to Shikkotsu Forest every night.
To get there, Tsunade summoned a small Katsuyu and had her notify Sage Katsuyu, who then reverse-summoned Tsunade and Uchiha Dan.
Their way back from Shikkotsu Forest was the same method used during Naruto's battle against the Six Paths of Pain, when he left a clone on Mount Myōboku and had Fukasaku summon him back to Konoha.
They each left a clone at home. At the appointed time, the clone summoned their real body back using a Summoning Scroll.
That month, Uchiha Dan kept busy. He listened as Tsunade explained the principles behind various ninjutsu and shared her combat experience, while also learning the Monster Strength Technique from her.
At the same time, he constantly tested and honed his various ninjutsu, while training in Shikkotsu Forest's Senjutsu. It was an incredibly full schedule.
On a mountaintop in Shikkotsu Forest.
Uchiha Dan quickly retreated, dodging Tsunade's attacks as his hands flashed through seals at lightning speed.
Snake—Horse—Monkey—Boar—Horse—Tiger!
He completed the six hand seals almost instantly. His movements were too fast to make out.
Uchiha Dan drew in a deep breath. As he retreated, his chest swelled as if he were drawing all the surrounding air into his lungs.
Meanwhile, Chakra surged through his body as countless fire elements rapidly gathered in his throat.
The next instant, a torrent of flames poured from Uchiha Dan's mouth, quickly coalescing into a huge fireball that hurtled toward Tsunade.
The air distorted in the fireball's wake, and the searing heat made it crackle and pop.
Fire Style: Great Fireball Technique.
As Uchiha Dan performed the jutsu, Tsunade, having sensed it coming, stomped her right foot against the ground. The tremendous force shattered the earth and sent chunks of rock flying into the air.
As the fireball neared, blue Chakra surged around Tsunade's right foot. She kicked the largest floating boulder with tremendous force.
But instead of breaking apart as expected, the boulder shot toward the fireball, propelled by the force of her kick.
Using the force of her counter-kick, Tsunade dropped rapidly to the ground.
Yet the instant her feet touched down, she lightly tapped the ground with her toe, wrapped in blue Chakra, and shot forward like a cannonball, catching up to the boulder.
Astonishingly, the ground wasn't damaged at all.
Monster Strength Technique: Ultra Precision Mode.
After years of striving under the pressure Uchiha Dan had put on her, and inspired by her granduncle and Second Grandfather, Tsunade had created this ultra-precise control mode for the Monster Strength Technique. It was essentially an advanced version of the technique.
In the past, every move she made caused massive destruction around her.
Now, when Tsunade entered Ultra Precision Mode, almost no energy escaped or went to waste during battle. She had complete control over her strength.
With her power so highly concentrated, Tsunade's speed in this mode was terrifying. It was practically Body Flicker Technique Pro Max Ultra.
In Ultra Precision Mode, Tsunade combined extreme speed, tremendous explosive power, devastating force, and exceptional physical recovery.
Whether or not she knew flashy ninjutsu didn't matter to Tsunade anymore.
It all happened in an instant.
From a distance, the huge boulder seemed to carve a path through the flames, with Tsunade close behind it, narrowly avoiding the fire.
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