The first step toward the Flying Thunder God

The sound of the cave ceiling cracking rolled like a string of muffled thunderclaps.

Rubble fell from the darkness, smashing the stone pillar beside Yamanaka Fūma. Half the old ninja's body was pinned beneath broken stone, blood spilling from his mouth, but his hand still gripped the iron box containing Kushina's notes.

White Snake poured out of the cracks in the rock.

They did not bite anyone. They only coiled around the iron box.

"Orochimaru wants those notes," the Nine-Tails said quietly inside the Sealing Space.

Naruto did not answer.

The exit was collapsing. Yamanaka Fūma was more than ten meters from the cave entrance, and the snakes were dragging the iron box in the opposite direction. Naruto only had two hands.

The laughter Orochimaru had left behind echoed from among the snakes.

"Naruto-kun, will you save the man, or what your mother left behind?"

Naruto drew two kunai from his sleeve.

One landed beside Yamanaka Fūma's feet.

The other embedded itself in the rock wall beside the iron box.

He had only inscribed the formula last night, copying it from Minato's surviving pages. One line was crooked; even the Nine-Tails had called it ugly.

"Brat, are you sure about this?"

"No."

Naruto forced Chakra into the formula.

His vision abruptly warped.

The next instant, he appeared beside the iron box, half of one foot landing among the snakes. He had missed his mark by nearly a meter. His left shoulder slammed into the rock wall, his bones giving a dull crack.

The White Snake lunged all at once.

Golden Chakra burst from his back, and a fox claw swept the snakes away. Naruto snatched up the iron box and poured Chakra into the kunai again.

This time hurt even worse.

It felt as though someone were pulling a red-hot thread out of the back of his head.

He vanished from the spot, and when he crashed down beside Yamanaka Fūma, his knee struck the rubble directly.

The old man stared at him, dazed.

"Flying Thunder God..."

"Shut up."

Naruto shoved the iron box into his arms, then gripped the stone pinning his body with both hands.

Nine-Tails Chakra surged along his arms.

The stone rose little by little.

Yamanaka Fūma gritted his teeth and pulled his legs free. Just as he crawled out, another huge section of the ceiling collapsed.

Naruto grabbed his collar and fixed his eyes on the distant kunai left near the entrance.

The third time.

The moment his Chakra stirred, hot blood gushed from his nose.

The Nine-Tails growled, "Stop! The formula's unstable!"

Naruto did not stop.

Space was like a sheet of paper forcibly folded in half.

The two of them slammed into the mud outside the entrance as the cave collapsed with a roar behind them. The blast whipped up dust and bent the nearby trees every which way.

Naruto lay facedown on the ground, his left shoulder numb and his ears ringing.

Yamanaka Fūma clutched the iron box and spent a long time catching his breath before asking quietly, "Why did you save both?"

Naruto wiped away his nosebleed.

"I don't play by his choices."

When Kakashi arrived, he checked Naruto's left shoulder first, then the seal on the iron box. Naruto thought he would ask about the Flying Thunder God first, but Kakashi only pushed a blood-staunching pill into his mouth. "You missed your mark twice just now." Naruto swallowed the medicine. "Not the third time." Kakashi looked at the White Snake Naruto had crushed underfoot. "The third time, the cave-in pushed you out. Don't count luck as part of your technique." Naruto wanted to argue, but the moment he moved his shoulder, the pain shut him up.

Kakashi pressed the paper packet of blood-staunching pills back into his hand. "Remember, next time, don't use yourself as the coordinates."

Inside the collapsed cave, a White Snake severed in two crawled out of a crack in the rock.

Its mouth opened, releasing Orochimaru's final words.

"Your first time using the Flying Thunder God, and you dared to use it three times in a row."

"Minato's son really is more interesting than the experiment records."

Naruto crushed the snake's head beneath his foot.

But a fresh snake-fang mark remained on the iron box.

Below the fang mark, a faint line of writing emerged.

"The Red Key is in Konoha."