Chakra test paper is special paper that reveals chakra nature. If Fire dominates, it ignites; Water, it dampens; Wind, it cuts; Lightning, it crinkles; Earth, it crumbles.
When Satoru concentrated his chakra, the paper first crinkled, then was sliced, and finally burst into flame.
"Lightning, Wind, Fire. Your chakra leans toward these three elements," the Third noted.
"Teacher Sarutobi, does that mean I can only use ninjutsu of these three elements?" Satoru asked innocently, as he truly didn't know.
"Of course not. Chakra test paper just shows predispositions. For example, with Water affinity, you can still use Fire techniques, just with more difficulty," Hiruzen explained. "Also, it shows innate affinity, which can change later."
The village head and his young disciple didn't dwell on chakra nature.
"The Sarutobi Clan excels in Fire Release; some members also handle Wind Release. Your chakra has affinity for both, so I can teach you those two ninjutsu. As for Lightning Release, I know a bit too.
"But I don't know your chakra reserves or limits. So I have an idea.
"Fight me," Hiruzen proposed seriously.
The transmigrator was slightly stunned.
"Teacher, you're serious?" he double-checked.
"Naturally. No need to hide your strength against me. Everyone has aces up their sleeve; don't hold back. I'll find a secluded spot, and you give it your all to beat me.
"I want to see your true limits," Konoha's head stated. "That way, I can train you better. What do you say?"
Satoru didn't know how to respond. Fighting the Third Hokage in his prime... If he didn't hide his power, he'd need explanations ready.
At that moment, the System's voice suddenly rang out:
[Host, hello! You've activated a new quest! Full-Power Fight! No need to hide your powers; do your utmost to defeat the Third Hokage! Reward: one use of "Turning the Useless into Treasure"!]
Satoru immediately wanted to exchange for Hiraishin. Though Flying Thunder God Technique was powerful, with Goro Goro no Mi's instant teleportation, Hiraishin's value had diminished. Exchanging it for something insanely cool would make the system holder even happier.
But defeating the Third Hokage—possible?
Tobirama's protege looked at Satoru with a smile and added:
"Don't worry; I know you have many abilities. Like the one blackening your hands or numbing people... If you don't want to reveal your aces, follow me.
"Keeping up is a show of strength too."
No sooner said than done. The Hokage shot toward Konoha's forest at incredible speed.
Seeing this, Satoru followed his mentor without using instant teleport. If using it, better in seclusion. What if someone saw him teleport? His ace would be exposed.
Soon, the boy left the village. Konoha's forest was on its outskirts. Rumor had it the First Hokage created it with Mokuton: Birth of the Wood World.
Finding the village head was easy. Several ANBU were nearby. Satoru sensed the Third's position and teleported right before them.
"Is that Flying Thunder God Technique?" Hiruzen was stunned. He, the Hokage, had raced here at full speed, yet Satoru teleported in the next second. Was this even human? At four years old! He could only assume Satoru had mastered Hiraishin.
Satoru had studied it, but hadn't used it just now.
The Third Hokage suppressed his emotions with effort and introduced:
"These are Konoha ANBU, barrier squad. They'll erect a barrier; nothing inside will be known."
"You can fight me without worry," Hiruzen said, eyeing the boy.
Satoru had no more reasons for concern and nodded.
"Alright." Satoru stood between the four ANBU with the village head. They quickly spread out, formed seals, and simultaneously used a barrier ninjutsu.
Soon, darkness enveloped Satoru and the Third. Even the four ANBU couldn't see inside.
The Sannin's teacher shed his Hokage cloak again and set aside his pipe. He had no intention of underestimating Satoru: he donned his helmet and battle gear meticulously.
Satoru needed no gear change; his clothes had damage reduction and appearance-altering effects.
"This is how I usually fight, Teacher Sarutobi. You really want my full power?" the boy confirmed again.
"Naturally," Hiruzen nodded firmly.
"Then let's begin!" Satoru shouted loudly, his aura shifting drastically.
"Armament Haki!" This time, he maximized Armament Haki on his fists and feet. Armament Haki: Hardening made them incredibly tough.
"Instant teleport!" Satoru boldly used Goro Goro no Mi to warp to his mentor.
"Amazing! Not Body Flicker Technique! True instant teleport?! Hiraishin?!" The Third was shocked to his core.
"Summoning Technique!" Konoha's head was even faster. The moment Satoru yelled "Begin!", he'd summoned his Diamond Staff.
Hiruzen Sarutobi spun the Diamond Staff with immense power and agility, fully embodying a great shinobi's stature.
"Boom!" Satoru's fist slammed into Hiruzen with force. The latter narrowed his eyes, growing dead serious. His reaction was lightning-fast. He horizontally thrust the Diamond Staff, perfectly blocking the boy's strike.
But Satoru had poured at least eight-tenths of his power into it. Tsunade's monstrous strength, Armament Haki, and Goro Goro no Mi lightning erupted simultaneously.
"Ah!" Even Hiruzen sharply inhaled, while Monkey King Enma, embodied in the Diamond Staff, cried out.
This power reminded the village head of his disciple Tsunade's monstrous might. Before him stood a mere four-year-old, yet with strength rivaling hers.
And it wasn't just strength. Satoru used Armament Haki: Hardening, so no weapon was needed—his body was the weapon. Even sharp blades hitting Satoru wouldn't harm much unless piercing his Haki fully.
Not to mention his other artifact—the wondrous clothes reducing damage and altering appearance: Sage's Cloak!
***
Read the story months ahead of the public release — early chapters are available on my Patreon: Granulan