Chapter 152: Learning the Current

Tenyu stood on a board above a dark wave and shouted with delight.

Maki rode the next crest several meters away. Both children wore flotation seals, impact guards, thermal layers, and tether lines connected to a broad woven whale beneath the surface. Tonbo's eagle circled above. Ayame watched through a linked observation seal from the support boat and retained the release that would end the exercise.

The ocean module followed months of chakra extraction, balance practice, swimming, shallow-water falls, and supervised surf. No child had been dropped into danger to discover courage. Each new condition arrived after the previous one became boring.

Before launch, both children had repeated the stop signals, cut a practice tether, inflated a backup float, and demonstrated that fear or fatigue could end the session without losing privileges. Tonbo inspected the weather twice. Ayame canceled one planned route because the support boat could not safely enter its recovery zone. Safety belonged to the whole system, not the strongest person present.

Wind pushed Maki sideways. She bent her knees, shifted chakra across the board, and yielded until the tether steadied. Tenyu tried to fight the same current and fell.

The woven whale reached him before the tether tightened. It lifted him above water, checked breath and consciousness through contact sensors, then carried him toward the support boat. Tonbo canceled Tenyu's next attempt until Ayame confirmed he had swallowed no water.

"I was fine," Tenyu complained.

"Then the medical check will prove it," Ayame replied through the seal.

Maki remained on the board because one child's fall did not automatically end another child's safe exercise. She completed the route and chose to stop when her legs began shaking. Tonbo praised that decision more than the successful ride.

Tenyu returned only after the medical check and chose a smaller wave. His second attempt lasted longer because he stopped fighting the board with rigid ankles. Maki shouted advice until Ayame reminded her that two voices during danger could confuse the signal. She waited, then showed him the movement from the boat.

The children were competitive without being turned into each other's instructors. Tonbo asked each to name one thing the other had done well and one condition that should end the next route. Their answers revealed whether excitement had hidden risk.

The children had completed the controlled form of Open Sky the previous season. Learning the Current developed different habits: balance under changing pressure, breath after immersion, direction without fixed ground, and trust in layered rescue. It did not make five-year-olds combat-ready.

While they rested, Tonbo unsealed a block of cedar. He formed the long sequence required by Sensory Lattice and placed two fingers upon the surface. Fine branches of Yin chakra spread along the grain, entered cracks, and mapped resistance. Tonbo selected four return categories before activation: moisture, rot, fiber direction, and foreign material.

Information arrived as structured sensation rather than vision. One corner held more water. A metal sliver lay beneath the opposite face. Early fungal decay followed a fracture invisible from outside. Tonbo ended the technique after six seconds.

The lattice withdrew. A headache formed behind his eyes.

Tonbo checked pulse, vision, balance, and recall against his baseline. The headache remained mild, but a word on the observation sheet took longer to recognize. He stopped further trials for the day. Cognitive fatigue was not a challenge to defeat by repeating the technique until failure.

The technique did not grow physical nerves inside wood. That description had misled his early design and encouraged unsafe assumptions about living targets. It created a temporary information network modeled upon sensory branching, using Yin Release to give abstract categories a form his mind could process.

The distinction improved both control and ethics.

Tonbo verified every result by cutting the test block after the children moved away. Three categories were accurate. The fungal decay extended farther than the lattice reported. He recorded the false boundary instead of adjusting the memory to fit success.

Current limits made the technique useless in combat: many hand seals, direct contact, short duration, predefined questions, and cognitive fatigue. On unfamiliar living systems, it could return pain, memories, or bodily signals Tonbo had no right or capacity to hold. For now, Sensory Lattice remained an inspection tool for nonliving material and consented medical models.

Its potential was still enormous. Barriers, seals, structures, poisoned equipment, and damaged machines all contained information ordinary perception missed. A technique did not need to kill anyone to become strategic.

Ayame reviewed the test log after the children's session. She asked why Tonbo had chosen four categories when three produced less fatigue in the previous trial. He admitted the improvement in seals had made him expect equal improvement in processing. The mistake became a rule: hardware stability did not prove mental capacity.

Tenyu wanted to try Sensory Lattice on the cut block. Tonbo let him inspect the visible grain without chakra and record predictions. Access to a parent's research began with observation, not inherited permission to use the technique.

At the Academy, Kiba threw five shuriken toward Sasuke and entered Four Legs Technique before they landed.

Sasuke's Sharingan followed every rotation. His own shuriken deflected Kiba's first pattern, and Great Fireball drove the Inuzuka toward the arena boundary. Iruka maintained a Water Release counter while Mizuki watched the safety lines. Akamaru remained outside because the exercise tested individual application.

Kiba changed direction too quickly for the fire to track. Three ordinary Clones appeared between him and Sasuke.

Iruka called the required separation as flame neared the arena boundary. Sasuke ended the technique at once, proving that control included stopping power rather than maintaining it for display. Mizuki reset the barrier before allowing Kiba's advance.

Sasuke saw chakra only in the real body. He attacked it.

The clones had never been intended to fool the Sharingan. They obstructed sight for the fraction of a second Kiba needed to launch wire beneath their images. Sasuke detected the metal late, cut one strand, and stepped into the second. The line wrapped his arms and disrupted the next seal.

Kiba stopped with a kunai at safe distance.

The wire carried a release knot Sasuke could reach if the match continued, but using it required both hands and attention Kiba had already denied him. Iruka inspected the restraint before declaring victory. A clever trap that injured the person caught would have counted as failure in an Academy exercise.

Sasuke escaped the rope after Iruka called the exchange, but the decisive moment had already passed. The Sharingan could identify a false body. It could not see through an obstacle merely because the obstacle was false. Both boys stored the lesson.

Sasuke stored another. Kiba's strength did not come only from clan senses. He designed choices around what an opponent expected from those senses. Beating him would require studying decisions rather than copying movements.

Kiba learned that Great Fireball forced more distance than his ordinary feints could tolerate. A single delayed turn would have trapped him against the boundary. Winning did not remove the need to change.