The next morning.
The training ground was already alive with movement.
"Oho! It's good to see your youth still burning so fiercely!"
Might Duy's booming voice rang across the field.
Ken, who had been running laps, turned his head slightly.
"You're here, Senior Duy," he said. "And Guy as well."
A short distance behind Duy, Guy raised a thumbs-up while running. His face was soaked in sweat, his breathing uneven. It was obvious he was already close to his limit.
Duy hadn't trained Ken directly. Instead, he had designed a physical training routine for him and left the execution entirely up to Ken.
Because of the recent mission, Ken hadn't been able to follow it perfectly.
Still, he made sure to meet the daily minimum.
A strong body was essential for what he planned to pursue next.
After a brief exchange with Duy, Ken shifted his attention to Guy.
He glanced at Guy's condition and muttered quietly, "Thankfully, Duy didn't go all out on me. Otherwise, I'd have collapsed long ago."
Guy finally couldn't hold back.
"Senior Ken!" he called out. "How is Kakashi doing?!"
Ken's lips twitched.
This guy really was something.
"He's doing well," Ken replied with a small smile. "It probably won't take long before Kakashi gets promoted to chūnin."
That was the truth.
Kakashi already had the strength and experience. In the original timeline, he had been promoted much earlier. Probably due to the butterfly it was delayed.
Ken thought for a moment, then added, "Guy, Kakashi seems a bit… off lately. Why don't you go challenge him? A few youthful duels might help."
He really wasn't suggesting it out of spite.
Now that Kakashi was his teammate, Ken felt some responsibility toward him.
But emotional speeches weren't his style.
Guy, on the other hand, was perfect for this.
Guy's eyes lit up as if injected with adrenaline.
"Yes! It's been far too long!" he shouted. "I'll challenge him immediately! And if I lose, I'll do five hundred push-ups!"
With that, he took off at full speed.
Duy, watching from the side, burst out laughing.
"Excellent!" he exclaimed. "This is youth!"
He gave Ken an approving nod and followed after Guy.
Ken watched them leave, his lips twitching again.
…Monsters.
Better to ignore them and focus on his own training.
He turned back toward the field and resumed his workout.
Later, in the shade of a tree, Ken could be seen chugging water in the distance.
After training all morning, Ken finally sat down beneath the tree's shade and unrolled several scrolls in front of him.
All of them contained Earth Release techniques he already knew.
Technically, reading jutsu in the open wasn't a good habit. In some cases, it could even earn punishment. Techniques were easy to copy—or steal.
"But the weather's too good to go inside," Ken thought with a faint grin.
He clapped his cheeks lightly.
"Focus."
His gaze swept over the scrolls.
Mud Wall. Mud Ball. Earth Spikes. Earth Ear. Subterranean Voyage. Earth Skin.
"I can already use Mud Wall, Mud Ball, Earth Spikes, and Earth Ear without hand seals," he muttered. "So first, I'll bring the other two to the same level."
Subterranean Voyage was the harder one.
Especially since he had skipped its lower-tier variant—the Hiding Like a Mole Technique.
Ken stopped hesitating.
He formed hand seals.
The moment he completed the final seal, his chakra responded. The earth beneath him softened, pulling him downward as if turning into mud.
"…It's similar to Earth Ear," he murmured. "No—rather than spreading outward, it's spreading downward."
"The density of the soil is changing."
He cut off the chakra flow.
The ground slowly hardened again, though not instantly.
Ken rested a hand on his chin.
"…Could it be?"
He formed the hand seals again, this time more slowly.
His focus turned inward.
Once he reached the stage of instant activation, he had discovered something important.
Instant techniques weren't impossible.
They required understanding.
If he focused while forming hand seals, he could trace the chakra's path—where it flowed, where its nature shifted, and which tenketsu released it.
If he could perceive that clearly, and his chakra control was sufficient, then he could manually replicate the process.
Of course, it wasn't simple.
Hand seals were like formulas.
Follow them, and the answer came automatically.
Without them, he had to solve everything step by step.
Tedious.
Difficult.
The only reason he could do this was because his control over Earth Release was exceptional.
And it was also why he could only achieve this level with Earth Release.
His thoughts raced, but his hands didn't stop.
After several repetitions, the pathways settled into memory.
"Earth Release: Subterranean Voyage."
Ken slammed his palm against the ground.
His body began to sink—
He immediately jumped back and canceled the jutsu.
Good.
The first step was complete.
He could now perform it without hand seals.
Next came the harder part.
Changing the release point from hands to feet.
That was far more difficult, especially since feet weren't as exposed as hands.
Still, with prior experience, he managed it after nine attempts.
The only reason he could try so many times was because he canceled each jutsu immediately after success, conserving chakra.
Ken stretched, a grin forming on his face.
It had taken an entire day, but visible progress was satisfying.
"I just hope we don't get another mission before I bring the rest up to the same level."
He glanced at the spread of scrolls in front of him.
There was still work to do.