Looks like you were played by Ōnoki—but the outcome wasn't bad.
Ōnoki brought the two of you together to discuss countermeasures. However, after learning from you about the connection between White Zetsu and the Akatsuki, he decided to hold the meeting on a massive floating boulder imbued with the Light-Weight Rock Technique to prevent any possibility of White Zetsu eavesdropping.
Ōnoki knew well that it was impossible for Iwagakure to dominate the shinobi world with its current foundation. Even if he somehow managed to forcefully stabilize it, chaos would eventually erupt. But as a political creature with ambitions of his own, he intended to use the intelligence you provided to strengthen Iwagakure while he was still alive—consolidating nearby shinobi villages and even merging military and political power so that the authority of the Daimyō would rest in the hands of the Tsuchikage.
This would lay the groundwork for a future where the Land of Earth could be unified!
...
You found that, in moments of real consequence, Deidara was surprisingly obedient and responsible. No wonder he had been chosen as Ōnoki's successor. Still, it was a shame that the Deidara you remembered had been so reckless and arrogant...
〖Month Ten〗
Under Ōnoki's strict orders, both you and Deidara learned the "Light-Weight Rock Technique." Working together with him, the three of you used Barrier and Sealing Techniques to create a massive floating island atop the mountain where the Will of Stone is said to be most tangible.
From then on, all training had to take place in secret on this island.
However, the upkeep of the island fell on you and Deidara—Ōnoki had begun to consolidate some of the Daimyō's authority and was often too busy with other matters.
You and Deidara agreed: aside from large-scale destructive jutsu, all other training—including Kekkei Genkai fusion—would be conducted solely on the floating island, to avoid detection by White Zetsu.
To prevent Deidara from collapsing the moment he was hit with a Sharingan genjutsu, you threw yourself into studying the entire Uchiha Genjutsu Compendium, then used Deidara as a live training dummy to toughen his resistance to Tsukuyomi.
〖Month Eleven〗
You completely refined the poisonous flame sealed within your body. Using a wide array of poisons, you continually enhanced its power until it reached a point where it could no longer be absorbed further.
You formed a small tri-colored flame dragon and realized its power had taken yet another leap.
If you'd possessed this level of control back when you'd just escaped from Konoha, you could've guaranteed that more than half the jōnin would be incapacitated—and that anyone below jōnin rank wouldn't survive.
It would've been far worse than what Ōnoki's intelligence report had described with understatement: "Numerous ninja injured, severe building damage, Tsunade returned and quickly healed the wounded."
Because your Three Tomoe Sharingan partially mimics the Mangekyō's traits, once you mastered the framework of Uchiha-style genjutsu—though you didn't have time to learn each technique—you still managed to grasp the two S-rank genjutsu derived from Genjutsu: Time-Space. Genjutsu: Time and Genjutsu: Space.
And their combined form—Genjutsu: Time-Space.
This made your genjutsu training with Deidara nearly indistinguishable from the real Tsukuyomi.
Originally, Deidara had planned to begin his Lava Release fusion this month.
But you stopped him.
Instead, you suggested using Genjutsu: Time-Space to simulate the process first, minimizing the risk of a failed fusion and any negative side effects.
〖Month Twelve〗
At first, you were puzzled—an entire year had passed, yet the Akatsuki hadn't come looking for Deidara.
But then it made sense. You'd killed Obito, dealt a severe blow to Konoha, and even wiped out a White Zetsu base. The butterfly effects of your actions weren't minor.
Not to mention, with you as his new sparring partner, Deidara—who should've been sneaking out of the village seeking the thrill of explosions—had instead locked himself away to train in Lava Release.
To test whether Genjutsu: Time-Space could fully simulate reality, you entered the illusion to practice the Rasengan—one of the purest forms of chakra shape transformation.
You also tested the release of Fire and Earth style ninjutsu.
The result?
—There were some differences from reality, but they were minimal!
So, without even reading the Second Tsuchikage's notes on Lava Release, you and Deidara both entered the Genjutsu: Time-Space and simulated the fusion process.
Once both simulations succeeded, you compared your results with the Second Tsuchikage's research. With your confidence bolstered, you were ready to attempt the real thing.
〖Simulation detected user survived one full year〗
〖To conserve simulator energy, simulation precision set to one year〗
At the start of the year, you and Deidara adjusted your chakra flows to perfection. Then, under Ōnoki's protection, you consumed a rare potion that aided in Kekkei Genkai fusion and minimized the backlash from potential failure.
Just like in the genjutsu simulation, your fusion of Fire and Earth release progressed smoothly.
As these two finely honed chakra natures merged within your chakra pathways—no longer distinct, but fusing into a new, nobler force—your bloodline began to stir violently.
But before long, the very core of your bloodline surged forth with an overwhelming aura that crushed the rebellious new power into submission, transforming it into an obedient force fully under your control.
Lava Release—achieved!
You woke from the fusion process, feeling the surging bloodline power coursing through your body.
Already highly attuned to blood due to your ocular techniques, you immediately sensed the magnitude of the transformation.
The boost from fusing a Kekkei Genkai far exceeded what you'd get from absorbing the blood of one or two Uchiha.
In fact, the increase was comparable to what you experienced after fusing a drop of Indra's bloodline!
Of course, that doesn't mean Indra's bloodline is equal to a single Kekkei Genkai.
After all, that drop came from a version of Sasuke who lacked significant power, hadn't matured, and whose Uchiha blood had been diluted over generations.
Still, this proves that artificially fused Kekkei Genkai don't inherently fall short of natural-born ones.
There are no defects!
In fact, artificial fusion has one major advantage:
You're the absolute master of this Kekkei Genkai.
You could even call yourself the progenitor—the zero-th generation inheritor!
There's no risk of things like unawakened bloodlines or bloodline illnesses. You have complete control.
And more importantly, it has the potential for continuous evolution and refinement.
For instance, evolving it into Dust Release.
By contrast, natural-born Lava Release users may seem powerful from birth—able to use the technique without fully mastering Fire and Earth.
But this strength is static and difficult to improve.
According to the Second Tsuchikage's notes, those born with a Kekkei Genkai would find it incredibly hard to fuse it with a third nature to evolve into a Kekkei Tōta. First, they'd have to erase the original progenitor's imprint, then re-code the bloodline, essentially turning themselves into the first-generation founder of the new lineage.
And even then, there's a high risk of the bloodline collapsing completely!
In the Tsuchikage's research notes, although he never went into detail about Lava Release, he did record an experiment involving Explosion Release—by far the most common natural Kekkei Genkai in the Land of Earth.
Only one person had ever succeeded in reversing a natural Explosion Release into an artificial one and becoming its founding ancestor again.
That person never reached the realm of Kekkei Tōta, but their achievement was still groundbreaking.
They established a stable Explosion Release bloodline.
Now, more than 80% of their clan members awaken Explosion Release.
That's why Iwagakure has so many explosive squads today!
Their inheritance rate even exceeds that of most Water Country bloodline clans, and even rivals the Uchiha.
Only the Hyūga—with an almost 100% activation rate—surpass them!
Likewise, Ōnoki possesses both Dust Release and its composite elements, including Lava Release. That's why Kurotsuchi inherited Lava Release as well.
However, as for Dust Release—being a Kekkei Tōta—it's likely too powerful to pass down intact...
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Pls Drop some Power Stones
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