[Lock Rhythm: World Purification], Sunny Spring and White Snow!

Xiao Yan stored the Void Sound-Suppressing Hou Right Arm Bone, bearing three hundred thousand years of accumulated power, into his Storage Ring. Satisfaction flickered in his deep black eyes.

This transaction had given both sides what they needed. Since the price had been paid in full, he naturally would not make any further excuses.

He turned to Xiao Xiao behind him and pointed toward a spot at the edge of the hall with an excellent view.

"Xiao Xiao, go sit cross-legged over there. Focus your mind and center yourself." Xiao Yan's tone became somewhat sterner.

"What I'm about to perform will greatly benefit your cultivation of the Nine Phoenix Flute's musical laws. How much you can comprehend from it depends entirely on your own fortune. Do not let your mind wander."

Hearing the gravity in her brother's voice, Xiao Xiao immediately put away her usual spoiled playfulness. She hurried to the designated spot, sat properly, closed her eyes, and adjusted her breathing.

After settling Xiao Xiao, Xiao Yan raised his eyes toward Mu En.

"Elder Mu, removing the mutated Evil Fire is an extremely delicate process. It cannot tolerate the slightest external interference. This will take a long time, so I'll have to trouble you to personally stand guard."

Mu En said nothing. One withered hand traced an arc through the air.

Pure Radiant Sacred Dragon Soul Power transformed into a solid golden barrier, sealing off the entire Sea God Pavilion hall.

His actions gave the most reliable answer.

With all preparations complete, Xiao Yan calmed his mind and spread his hands before his chest.

Purple-gold and moon-white divine radiance tore through space as the ancient, timeworn Fuxi Zither floated steadily in the air.

"Buzzz—buzzz—buzzz—buzzz—"

Four consecutive deep, weighty hums echoed through the hall.

As the Fuxi Zither appeared, four Ten-Thousand-Year Spirit Rings, deep as ink, rose one after another from beneath Xiao Yan's feet.

Mu En's cloudy eyes abruptly narrowed. Yan Shaozhe's mouth fell open as well, his gaze locked onto those four black Spirit Rings that defied all common sense in the world of soul masters. His heart pounded wildly beyond his control.

Yet Xiao Yan did not stop.

His hands hovered above the strings as vast spiritual power surged forth like a burst dam.

Deep within his sea of consciousness, the Fuxi Bagua Formation Map spun madly.

"Merge."

Xiao Yan parted his thin lips and uttered a short syllable.

The next moment, the four independently pulsing Ten-Thousand-Year Spirit Rings actually began overlapping toward the center.

Violent Soul Power collided and compressed, yet under Xiao Yan's precise control through his immense spiritual power, no rejection occurred at all.

Mu En and Yan Shaozhe exchanged a glance, both seeing undisguised shock in the other's eyes.

The same two words crashed into the minds of master and disciple.

Ring Fusion!!!

Throughout the ten-thousand-year history of Douluo Continent, soul masters capable of achieving this at such a cultivation level had been exceedingly rare.

Dazzling light burst forth beneath the Fuxi Zither as the four black Spirit Rings completely fused into one.

When the light faded, a Hundred-Thousand-Year Spirit Ring, crimson red throughout, quietly hovered beneath Xiao Yan's feet.

The bloody halo unique to a Hundred-Thousand-Year Spirit Ring cast the entire Sea God Pavilion hall in a grim red glow.

Ring Fusion's exclusive skill: [Lock Rhythm: World Purification].

This skill fused every characteristic of his first four Ten-Thousand-Year soul skills.

It could magnify the purifying and refining effects of zither music tenfold or even a hundredfold, while constructing a completely sealed internal musical space that locked every note firmly within the target's body for relentless, high-frequency cycles of cleansing.

Xiao Yan's ten fingers moved in unison, dancing across the Star Thread strings.

Sunny Spring and White Snow.

This elegant ancient melody, passed down through the ages, revealed its true might under the enhancement of the crimson Spirit Ring and in conjunction with the Fuxi Zither, an ancient divine artifact.

The instant the zither music began, every note transformed into visible streams of white light as it left the strings, accurately slipping into Ma Xiaotao's glabella.

Ma Xiaotao's body suddenly tensed.

The meridians within her body instantly became a massive echo chamber.

The impassioned yet clear zither music surged wildly through her blood vessels, bones, and organs. Every cell endured the high-frequency cleansing of sound waves.

The black-red Evil Fire that had once writhed and lashed about encountered the sound waves of Sunny Spring and White Snow and let out shrill, soundless screams as it collapsed across large areas.

The Evil Fire impurities shattered by the sound waves seeped out through Ma Xiaotao's pores, turning into waves of foul-smelling black smoke that dissipated within the golden barrier.

Meanwhile, deep within her dantian, after all violent and evil impurities had been removed, a cluster of pure crimson flame slowly took shape.

It was the source of Ultimate Fire, free of any impurity and brimming with brilliant divine majesty.

Although the three people in the hall could not hear the zither music's specific melody, the pure Dao resonance spilling from Ma Xiaotao still benefited them immensely.

Xiao Xiao immersed herself in that Dao resonance, and the Nine Phoenix Flute martial soul within her gave a joyful hum.

Mu En and Yan Shaozhe only felt their minds become clear.

The purification process was exceedingly long.

Several hours passed.

The cracked, charred skin on Ma Xiaotao's body began peeling away in large patches, revealing delicate new skin as smooth as white jade.

Her twisted face also regained its former brilliance. Her complexion grew increasingly rosy, while her breathing became steady and deep.

Fine beads of sweat appeared on Xiao Yan's forehead.

Forcibly maintaining a Hundred-Thousand-Year-level Ring Fusion skill while using spiritual power to guide sound waves through another person's meridians for removal consumed an ocean of energy.

A cornered beast still fought.

Sensing the arrival of their doom, the remaining mutated Evil Fire began a frenzied counterattack.

Part of the Evil Fire actually followed the bridge of spiritual power Xiao Yan had extended, transforming into nearly imperceptible black-red venomous snakes that shot toward his wrist.

"Sizzle!"

The moment the Evil Fire touched Xiao Yan's skin, it gave off a piercing sound of corrosion.

Xiao Yan frowned slightly. The Innate Qi within him circulated on its own and crushed that strand of Evil Fire.

Mu En and Yan Shaozhe, who had been closely watching the situation, were greatly alarmed at the sight.

They had witnessed the terrifying corrosive power of that mutated Evil Fire.

Even someone with Xiao Yan's foundation had been affected despite being prepared. It seemed the backlash risk the youth had mentioned earlier was not merely an excuse to inflate his price!

Seeing that its ambush had failed, the remaining Evil Fire swiftly retreated and entrenched itself around Ma Xiaotao's heart, intending to use it as its final fortress.

At this stage, Xiao Yan dared not be careless.

The heart was the source of a person's vitality. With the slightest mistake, if the sound waves shattered her heart meridians, Ma Xiaotao would perish on the spot.

He slowed his playing. The melody became gentle and soothing, turning into countless invisible surgical blades that painstakingly stripped away the corruption around her heart bit by bit.

The sun rose and the moon set.

An entire day and night passed within the Sea God Pavilion hall.

Until noon of the following day, sunlight filtering through the window lattice fell upon the Golden Tree.

Xiao Yan pressed both hands heavily onto the strings.

The final trace of black-red impurity lodged within the heart meridians was annihilated.

The crimson Hundred-Thousand-Year Spirit Ring dissolved into motes of light, and the Fuxi Zither vanished back into his body.

After maintaining such intense concentration for a full day and night, a hollow sensation rose from his sea of consciousness.

Xiao Yan staggered and took half a step back.

Xiao Xiao, who had long since emerged from meditation and stood watch nearby, reacted quickly. She rushed forward at once, firmly supporting her brother with her shoulder, her face full of distress.

Seeing Xiao Yan finish, Yan Shaozhe quickly stepped forward, just about to ask about the situation.

"Screee!"

A phoenix cry that pierced metal and split stone suddenly erupted from within Ma Xiaotao, soaring into the heavens.

The cry no longer carried its former violence and wickedness. In their place stood the majesty and nobility of a king.

Ma Xiaotao, seated on the meditation cushion, abruptly opened her eyes.

Two dazzling crimson beams shot from the depths of her gaze.

The pure aura of fire's origin exploded outward from her body, instantly sweeping through the entire hall.

Had Mu En's barrier not still been in effect, the surrounding ancient wooden structures would likely have turned to ash in an instant.

Ma Xiaotao rose to her feet, her long red hair whipping wildly amid pure crimson flames. She looked like a phoenix reborn from fire, descending into the world.

Ultimate Fire, without a doubt!!!