The snow had long melted by the time Naruto opened his eyes again.
He was deep underground — a cavern sealed by chakra stone, hollowed centuries ago by the Uzumaki ancestors.
He didn't speak.
Didn't breathe heavily.
He simply stood in silence, eyes closed, as the weight of everything behind him turned into a blade pointed forward.
Kurama spoke first.
"So... you're really going through with this."
Naruto opened his eyes.
"I forgave them," he said, voice low. "But I'll never follow the path they chose."
The toad contract, the prophecy, the cycle — it was all ash now.
Only vengeance remained.
Weeks passed in silence.
Then months.
But Naruto wasn't idle.
He began collecting.
Scrolls hidden in abandoned roots of Uzushio's ruins.
Fragments of battle intel stored in his memory — things Jiraiya had once mentioned when rambling about the "old ways."
He remembered a single moment during a filler mission with Yamato and Kakashi — something about a place where toads trained in natural energy. Mount Myōboku. He remembered the way Jiraiya's eyes had changed during that arc. The explanation of senjutsu.
"Why didn't they teach it to me?" he once wondered.
Now he knew.
Because they were afraid of what he would become if he stopped needing them.
He didn't ask permission.
Didn't seek guidance.
He started absorbing natural chakra through force — using ancient chakra siphons carved into the ruins by the first Uzumaki seers.
Each one corrupted by time.
Each one poisonous to the unworthy.
He barely survived the first attempt.
His skin turned black with seal marks. His eyes bled. His spine twisted for hours while Kurama poured chakra through his core to keep him from collapsing.
But he adapted.
By the fourth week, he could hold the flow.
By the eighth, he could bend it.
Not like the toads — no bulging eyes, no sage oil.
He didn't want mutation.
He wanted control.
So he created his own form: internalized, clean, silent.
Sage chakra that ran like mercury through his veins without changing his form.
Kurama was shocked.
"You're not even channeling animal chakra."
Naruto nodded.
"This is Sage Mode. But in human language."
By the third month, he had mapped his elemental affinities in full.
Wind — still his dominant trait.
But fire — sharpened by hatred, amplified by chakra control.
Lightning — unstable, but dangerous.
Earth — harder to mold, but ideal for seal-carving and battlefield reshaping.
Water — still weak, but paired perfectly with his sealing techniques.
Kurama instructed when needed, correcting form with ancient fox knowledge once used to tear through entire war camps.
He broke down jutsu.
Rewrote them.
His first successful rewrite was a Wind-Fire hybrid: a spiraling orb laced with a reverse current of flame.
Unstable.
Explosive.
But efficient in short-range bursts.
He called it "Karyuuzan" — Fire-Dragon Spiral.
Not because it looked like a dragon.
But because it devoured the field like one.
Over time, Naruto became obsessed with speed.
Not just movement — but execution.
Every technique he built had to activate in one seal cycle or less.
Kurama asked once, "Why the rush?"
Naruto replied, "I won't get second chances in the next war."
His eyes changed.
Still red — not Sharingan.
Not yet.
But his expression was different now.
Colder.
Focused.
Unforgiving.
Each day, he remembered every jutsu he had seen as a child. Every forbidden move Danzo had whispered about. Every elemental clash from the Chūnin Exams. Every summoning scroll from the Second Shinobi War hidden beneath ruined archives.
He gathered scrolls from villages he had raided.
Took tools from graves no one dared visit.
By month ten, he had seven elemental scrolls.
Three ancient Uzumaki tomes.
And the full breakdown of chakra nature manipulation down to yin and yang.
All stored within a dimensional pocket seal he had created from scratch — a modified extension of the Four Symbols Seal.
Even Kurama said nothing when he saw it.
Because he knew.
This was no longer the boy he had been sealed inside.
This was a man building his own language of destruction.
And the world had no idea what was coming.