The treatment had just consumed a great deal of Tsunade's chakra and mental energy. She was visibly exhausted.
Yusuke came straight to her side and let her lean against him.
"Only a small amount of Senjutsu Chakra has been formed through the initial fusion. I'm still a long way from fully entering Sage Mode."
Yusuke let out a long breath, his voice weary but full of excitement.
Sage Slug: She hadn't eaten much dinner, so why did she feel so full?
Sage Slug's voice carried a note of approval. "This is an excellent start."
"Your talent and willpower have both exceeded my expectations."
"Rest for a while and remember this feeling. Senjutsu training can't be rushed."
Yusuke nodded and didn't push himself.
However, just as this Senjutsu Chakra was about to run out, a sudden change occurred within Yusuke.
The faint Senjutsu Chakra inside him was instantly engulfed by a darkness that appeared out of nowhere.
A violent consciousness, dormant in the deepest part of his body, abruptly awakened.
It caught the scent of something incredibly delicious.
After annihilating the Senjutsu Chakra Yusuke had gathered, it took control of his body instead.
At a hundred times the intensity of before, it frantically drew in the Natural Energy of Shikkotsu Forest.
This was exactly what it wanted.
"Yusuke, have you gone mad?! Stop!"
Tsunade turned pale with horror.
This whale-like rate of absorption far exceeded the safe limit. The Natural Energy would instantly shatter the balance between physical and spiritual energy.
There was only one possible outcome for Yusuke: his body would be completely broken down by the Natural Energy, leaving not even a trace of his remains!
Ignoring her own exhaustion, Tsunade lit her palms with the green glow of the Mystical Palm Technique once more. She tried to intervene by force and stabilize the raging flow of energy inside Yusuke.
But most of Yusuke's body was already under the control of that dark entity. His face twisted with intense pain and struggle.
With only a sliver of consciousness remaining, he summoned the last of his strength, poured chakra into his arm, and shoved Tsunade away from him.
"Stay back!"
A gentle force sent Tsunade stumbling backward, away from the center of the energy vortex.
Immediately afterward, the suction emanating from Yusuke surged again.
With him at its center, it was as if an invisible black hole had formed, drawing the Natural Energy around him into his body in a frenzy.
The surface of his skin began to bulge irregularly, as if something were thrashing around inside him. His meridians groaned under the strain.
For the first time, Sage Slug's gentle voice grew grave. "There's a foreign presence inside him, using the Natural Energy to awaken."
"If this continues, he'll die. There's no other possible outcome."
Before the words had even faded, dozens of tiny slugs split off from Sage Slug's body. Like a blue tide, they rapidly crawled toward Yusuke.
One by one, they attached themselves to key points on Yusuke's body, their bodies glowing with a soft healing light.
They tried to use their own life energy to counteract and guide the Natural Energy rushing out of control into him, stabilizing his body, which was on the verge of collapse.
At that moment, Yusuke's perception was forcibly drawn inward, and his "sight" plunged into chaos.
The network of meridians that had once balanced the three kinds of energy had now been stained an ominous dark color.
The dark entity was no longer a vague shadow.
After absorbing a vast amount of Natural Energy and Yusuke's own chakra, it expanded at a furious rate.
It became a colossal, sky-spanning black cloud that filled his mental space.
The cloud churned, radiating a cold, savage force.
Then it began to contract and condense.
A shape gradually took form. Its skin was as dark red as blood, covered in sharp bone spikes.
Its head resembled that of a dragon, but was more twisted and grotesque. Four blood-red Cross-Star Eyes gleamed with pure destructive desire.
Its enormous jaws parted, revealing layer upon layer of dagger-like fangs.
"Roar!"
A savage roar rang out, making Yusuke's consciousness reel.
"This is... Tyrant!" Yusuke recognized it at once.
It was the source of Incursio, the legendary dragon-shaped Danger Beast said to possess extraordinary adaptability and survivability.
Even after being made into an Imperial Arms, it had retained its vitality. That was why the Imperial Arms Incursio could evolve without limit.
Yusuke's long-held fear had become reality.
Incursio's strength went without saying, but its danger lay in the way its material could turn on its user the more it was used.
In the end, the user would be completely transformed into a dragon and lose their sense of self.
Yusuke had used it with great care every time, afraid of overstimulating the dormant beast.
But to Tyrant, the vast, pure Natural Energy of Shikkotsu Forest was the perfect nourishment.
No longer content to lie dormant, it rapidly awakened and grew under the stimulation of the Natural Energy.
Its next step would be to consume Yusuke's spiritual core and make him a sacrifice for its own rebirth.
"Roar!"
Tyrant's consciousness roared again, savage and violent, and charged straight at Yusuke's mind.
Its four Cross-Star Eyes locked onto the core of Yusuke's consciousness, brimming with a desire to devour and possess him.
On the outside, Yusuke's condition rapidly deteriorated.
The tiny slugs attached to him trembled violently. The stabilizing energy they sent into him was quickly canceled out by a darker, more voracious force.
The Sage Mode markings on Yusuke's body flickered. His silver hair showed signs of turning dark red, and fine, scale-like bumps began to appear beneath his skin.
"A powerful negative will is taking control."
"Little Tsunade, move farther away. I'm going to increase my energy output and try to restrain this will."
Sage Slug's voice was graver than ever. It could sense that the monster inside Yusuke was every bit as powerful as her at its peak.
More tiny slugs split off from Sage Slug's main body and surged toward Yusuke like a blue tide.
This time, they weren't trying to heal him. They were weaving a cage out of Natural Energy, sealing the dark will inside his body.
Within him.
"I won't let you have your way." Yusuke growled, enduring the tearing agony in his soul as he quickly considered a solution.
"The Senjutsu of Shikkotsu Forest is built on balance and vitality..."
"While Tyrant represents destruction and devouring."
"Where there is yin, there is yang. Where there is prosperity, there is decline. Where there is life, there is destruction. Their very natures oppose each other!"
An extremely dangerous plan took shape in his mind.
His next move wasn't to drive Tyrant out or suppress it, but to... tame it.
He would use the balancing nature of Shikkotsu Forest's Senjutsu to shackle this savage beast.
He abandoned the futile attempt to wrest control of the energy directly from the black cloud and instead focused all his attention on guiding the Natural Energy.
Yusuke deliberately guided the physical and spiritual energy still left in his body, fusing them in an exceptionally precise ratio.
The energy quickly wove itself into a net, which wrapped around Tyrant's dark, savage consciousness of its own accord.
"Roar!"
Tyrant's consciousness let out a cry of pain.
Natural Energy, so brimming with life, was its favorite thing. But only when it wasn't infused with someone else's will.
Yusuke had fused his own chakra with the Natural Energy, making it impossible for Tyrant to devour.
But Tyrant was simply too powerful. Its four blood-red eyes flared brightly as it struggled frantically, trying to tear apart the bonds of energy.
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