The sheer, explosive kinetic force of Yoriichi's horizontal block met the descending weight of the serpent. The air pressure ruptured between them, kicking up a massive wave of swamp water as Yoriichi gritted his teeth, his boots sinking deep into the mud, forcefully pushing the horrifying beast back into the fog.
HISS!
The serpent recoiled, its fifteen-foot body thrashing wildly against the shallow water and the mangrove roots. Its neon-blue lure throbbed with a sickly, rhythmic pulse as it reoriented its massive jaws toward the intruders.
As they immediately took up tactical positions on opposite sides of a thick tree root, Yoriichi's crimson eyes narrowed, his Transparent World vision dissecting the creature's internal circulatory flow and skeletal structure.
"This is the one," Yoriichi quickly relayed to Xiao Yu, raising his voice over the hissing of the thermal vents. "This is the borderline aura I sensed earlier. It is a Miasma-Swallowing Python."
His gaze pierced the beast's thick, dark-green scales, analyzing the erratic flow of its beast core.
"It has newly broken through to Rank 3," Yoriichi continued his rapid analysis. "Its internal energy is incredibly chaotic, making its physical defense slightly weak and inconsistent. It did not ambush us for territory... it wants to devour us to absorb our Dou Qi and stabilize its new realm, exactly as we are trying to stabilize ours."
Xiao Yu nodded in profound understanding. In the Dou Qi Continent, humans hunted beasts for their cores, and beasts hunted humans for their refined flesh and Qi. It was the purest, most brutal cycle of nature.
As the python lunged again, snapping its jaws in a terrifying horizontal sweep, they simultaneously defended themselves by leaping upward, jumping through the lower branches of the mangrove trees to avoid the acidic venom dripping from its fangs.
Landing gracefully on a mossy branch, Xiao Yu closed her eyes for a brief second.
When they opened, the vibrant pink-red irises gleamed with an unyielding, freezing resolve. She was a Dou Shi now. She possessed a liquid crystal core. She needed to test the absolute limits of her new realm without relying on her brother to execute the finishing blow.
"Okay," Xiao Yu stated, her voice carrying an unnatural, frosty echo. "Let me take care of it."
Before Yoriichi could object, she leaped from the branch, dropping directly into the python's strike zone.
Instantly, she channeled her liquid Dou Qi. Instead of just coating her azure whip; jagged, razor-sharp spikes of solid ice erupted along the entire length of the leather, transforming the whip into a terrifying, flexible sawblade.
She engaged the beast head-on.
The Miasma-Swallowing Python hissed violently, whipping its massive, scaled tail through the fog to crush her.
Xiao Yu didn't retreat. She flicked her wrist, sending her spiked whip coiling around the incoming tail.
Screeeech!
Sparks flew as the ice spikes ground against the python's thick scales.
'It's heavy... incredibly heavy,' Xiao Yu's internal monologue raced as she felt the sheer, raw physical power of a Rank 3 beast attempting to rip the whip from her hands. 'But its movements are entirely predictable. It relies purely on brute force and venom. There is no technique. I must disrupt its equilibrium.'
She violently yanked the whip backward, using the beast's own momentum to throw it slightly off balance, then immediately launched a counterattack, lashing her whip across the python's exposed underbelly.
The battle became a violent, high-speed dance of evasion and striking. The python would attack with terrifying lunges and sweeps of its tail, and Xiao Yu would defend, using her frosty Dou Qi to create brief, icy barriers to deflect the blows, before instantly counter-attacking with blindingly fast, spiked lashes.
Yoriichi, having secured a stable position on a high branch a respectable distance away, quietly sheathed his katana. He sat down, resting his arm on his knee, and intensely observed her footwork and Dou Qi control.
Minutes passed. The humid, fog-choked environment of the wetlands began to take its toll. The python was bleeding from dozens of shallow, freezing gashes across its scales, its movements becoming slightly sluggish as the frost seeped into its cold-blooded muscles.
However, Xiao Yu was also visibly tiring. Her chest heaved, and the frosty aura around her flickered. Managing liquid Dou Qi required significantly more mental stamina than gaseous Qi.
Realizing a battle of attrition would eventually favor the beast's massive stamina pool, Xiao Yu forcefully kicked off the python's snout, creating twenty feet of distance between them.
She landed in the ankle-deep water, her boots splashing softly.
She took a deep, localized breath, pulling the freezing air entirely into her lungs.
"Ice Breathing..." Xiao Yu whispered.
Up on the branch, Yoriichi's eyes widened slightly in shock.
Xiao Yu lowered her center of gravity, slithering low to the water like a coiled serpent herself. The aura around her fundamentally changed. The ambient, passive coldness instantly condensed, becoming terrifyingly sharp, absolute, and profoundly freezing.
"...First Form," Xiao Yu continued, her eyes locking onto the massive python.
She launched herself forward, moving with a bizarre, frictionless grace, her boots sliding perfectly across the surface of the swamp water.
"Phantom Slide..."
As she moved, she directed her spiked whip in a continuous, mesmerizing figure-eight pattern, flawlessly mimicking the slithering, hypnotic movement of a serpent. The sheer kinetic speed of the whip generated dozens of small, condensed ice spikes that shot forward through the fog like a barrage of frozen daggers.
The Miasma-Swallowing Python, confused by the hypnotic movement, thrashed its head to defend against the incoming barrage. Its thick scales deflected most of the spikes, but its chaotic, panicked movements caused it to miss a crucial spot.
Squelch!
A three-inch ice spike bypassed its scales and buried itself deep into the python's left eye.
The beast shrieked, a horrifying, guttural sound that shook the wetlands. It reared back, exposing its throat in absolute agony.
Xiao Yu didn't hesitate. Using the momentum of her Phantom Slide, she closed the distance instantly. Her whip cracked through the air. The razor-sharp, ice-spiked tip of the leather slithered past the beast's thrashing jaws and violently pierced its remaining right eye, blinding it completely.
With a final, desperate exertion of her Dou Qi, she coiled her whip around the blinded beast's neck, leaped into the air, and used the full weight of her falling body to strike heavily downward, snapping the python's neck against a massive mangrove root with a sickening crack.
The beast thrashed violently for a few more seconds, unable to stop the dark, venomous blood pouring from its mouth, ruined eyes, and the freezing gashes across its body. Finally, with a last, violent shudder, the massive Miasma-Swallowing Python collapsed heavily into the murky water, completely dead.
Xiao Yu landed lightly on the massive, scaled corpse. She heaved a massive, exhausting sigh, her spiked whip returning to its normal leather state.
Up in the canopy, observing the climax of the fight, Yoriichi remained perfectly still.
When he had heard her whisper a new breathing style name—Ice Breathing—a profound, bittersweet wave of nostalgia had washed over his ancient soul.
His memories had instantly been dragged back to a previous life, a life filled with snow, blood, and demons. He remembered the sprawling courtyards of the Demon Slayer Corps. He remembered how his Sun Breathing had been too powerful, too fundamental for anyone else to master.
He remembered how his fellow Hashiras, unable to wield the Sun, had stubbornly refused to give up. Instead, they had adapted. They had broken down the fundamental principles of his technique and fused them with their own unique talents and physical capabilities, creating entirely new, localized combat styles. Water. Flame. Wind. Stone. Thunder.