*Content Warning: This chapter contains mature themes, violence, blood, and morally dark actions. Reader discretion advised.*
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The door closed softly behind them as Leon and the old man stepped back into the house. The evening meal was simple but warm — thick slices of bread dipped in herb-infused broth, a handful of dried fruits, and tea steeped from leaves gathered in the forest. They ate in companionable silence, the only sounds the crackle of the low fire and the occasional rustle of wind against the shutters.
After the dishes were cleared, the old man settled onto his mat near the hearth. Within moments, his breathing deepened into the slow, even rhythm of sleep. Leon lay on his own mat by the window, arms folded behind his head. Moonlight poured through the glass in pale silver streams, painting the room in soft, ghostly hues. The moon itself hung full and bright, a perfect circle of cold light against the deep velvet sky.
Leon stared at it, a wide smile slowly spreading across his face.
"Hm… no matter how many times I think about it… I will have to use Soul Resonance Art to master the old man's swordsmanship. This is quite strange… but for some reason my physique isn't working when I am training. Well… to put it simply… I don't know about it yet — about how my physique even works. So I guess I have to rely on Soul Resonance Art for the time being."
He tilted his head toward the sleeping old man, voice dropping to a murmur.
"I don't even know how much longer my body can endure after I use Soul Resonance Art… but what should I do? Is there any other way? I don't even know how much more difficult the old man's swordsmanship is going to be."
A thought drifted through his mind like moonlight on water.
"Now that I think about it… Echo Flow Technique is like my physique in some ways."
He closed his eyes, letting the realization settle.
Both techniques were rooted in adaptation — but where his Limitless Mimic Physique absorbed, reshaped, and exceeded, Echo Flow was subtler. It moved with the rhythm of the world. It sensed the invisible echoes left by every action — the faint tremor of a footstep, the whisper of a blade through air, the shift of breath in an opponent's lungs. It adapted, predicted, and merged with the enemy's flow.
Compared to his physique, Echo Flow was nothing — a shadow of the same principle. Yet it would certainly help. If he could truly master its rhythm… if he could fuse its foresight with Soul Resonance's unity… perhaps the backlash would lessen. Perhaps he could push further without his body collapsing.
Leon lay still for a long time, moonlight tracing patterns across his face. The house was quiet except for the old man's steady breathing and the distant sigh of wind through the trees.
He rose silently, careful not to wake his host. The wooden floor was cool beneath his bare feet. He stepped to the center of the room, sword in hand — the same wooden blade from training. He closed his eyes.
Soul Resonance came first — familiar now, threads of energy weaving from soul to body, sword, and surroundings. The room seemed to breathe with him — the air, the wood, the faint warmth of the dying embers all aligning to his will.
Then he reached for Echo Flow.
It arrived like a ripple across still water — subtle, almost imperceptible. He felt the echoes: the slow settling of dust motes, the faint creak of beams cooling in the night, the rhythm of the old man's heartbeat across the room. He moved — a single step, slow and deliberate. The floor answered, guiding his weight. He raised the sword. The air parted before the blade, leaving invisible trails he could sense, predict, merge with.
He began to flow.
A cut — not fast, but perfectly timed with the room's rhythm. The blade sang softly as it passed through empty space. He pivoted, feeling the echo of his own previous step, adjusting instantly. Another cut — this one angled to follow the natural current of air drifting from the window. The motion was smoother than before, less effort, more inevitability.
He pushed deeper.
Soul Resonance bound everything — unity of self, weapon, world. Echo Flow layered atop it — sensing, predicting, merging. The fusion was fragile at first — the backlash of Soul Resonance still clawed at his core, threatening to tear the connection. But he held it. He breathed through the pain. He let the techniques speak to each other.
What emerged was not two separate arts, but something new — a single current. Soul Resonance gave him oneness; Echo Flow gave him anticipation. Together they reduced friction. The backlash didn't vanish — it lessened, spread thinner, like a river finding more channels instead of flooding its banks.
Leon moved faster — cuts chaining into combinations he hadn't practiced. The sword no longer felt heavy; it felt inevitable. Every motion carried the weight of the world's rhythm behind it.
He stopped, breathing hard but steady. Sweat glistened on his skin. The moon had shifted slightly in the window — time had passed without him noticing.
He looked at the blade in his hand.
"This… could work."
The night deepened. Leon returned to his mat, mind buzzing with possibilities. Tomorrow would test him again.
Dawn arrived gentle and inevitable.
The old man was already up, preparing breakfast — the same simple meal as before. They ate in silence, the air between them charged with unspoken anticipation. When the bowls were cleared, the old man rose and gestured toward the clearing.
Leon followed, sword in hand.
The old man stood in the center of the training ground, his own wooden sword resting lightly against his shoulder. His expression was serious, but a wide smile played at the corners of his mouth.
"Well, Leon… you must be certainly tired of this place. So I am just going to teach you the very original and highest form of this technique. As you know… my master was the one who taught me this swordsmanship… and it is going to be too hard for you from now on — even if you use your technique. This will still be the most intense training you can ever face."
He paused, eyes gleaming with quiet intensity.
"You have to push past your limit."
Leon tilted his head, curious.
"Well, old man… the thing is… you keep calling your swordsmanship only 'swordsmanship.' Isn't there a name or something like that?"
The old man's smile widened — bright, almost boyish with excitement.
"Ah… I was waiting for you to ask me this. Well… I should probably tell you now. This… after all… is the swordsmanship my master made. It is named — Celestial Edge Flow."
Leon's eyes widened.
"Celestial Edge Flow…?"
The old man laughed — warm, genuine, carrying echoes of memory.
"Hahaha… yes. I don't know why he named it that. My master was the one who chose the name, after all. But it fits. The blade cuts through emptiness… through hesitation… through anything that stands between you and your path. That is its essence."
Leon stared at the old man for a long moment, the name settling into his mind like a key turning in a lock.
"Celestial Edge Flow…"
The old man raised his sword — no longer playful, but deadly serious.
"Now… let us begin."