The Protagonist's Sister Is Actually The Strongest

[The Demonic Throne {The Greed That Consumes Everything} declares that their Avatar has been specifically handpicked to completely shut down any attempt at stopping his army.]

“…”

The Spherical Demon began floating downward, accelerating faster and faster until its entire body released a shockwave of combined light and darkness—copying the Heavenly Empress’s attack!

FLASH!

“That thing’s copying me now?!”

The Heavenly Empress grew frustrated. She rapidly waved her fan, unleashing a storm of blinding light from her Aura, enveloped by the Flames of Hope.

“{Heavenly Flame Tornado of Hope}!”

FLUOSH!

The tornado collided with the massive wave of darkness and light. Both elemental attacks erupted and exploded midair, generating a gigantic tremor that rippled across the rest of the sky.

BOOOMMM!!!

The attack was successfully negated, but the demonic sphere appeared above the Heavenly Empress, moving at a speed that surprised even her.

“You…!”

“BLEH…”

The creature made a strange sound, opening its jaws and pointing its tongue at her!

It tried to wrap its tongue around her and devour her in one swift bite, just like a frog capturing prey.

However…

“Don’t underestimate me.”

“{Divine Venerable Imperial Armament}: {Six-Armed Bodhisattva of Heaven’s Redemption}”

Her eyes blazed with righteous fury as she summoned her Imperial Armament Powers. Six enormous golden arms manifested, each wielding swords of light and flames of hope.

“{Echo: Manjushri’s Six Heavenly Blades}!”

All six gigantic swords surged toward the spherical demon, unleashing a relentless barrage of cutting attacks. The demon’s single eye widened for a moment. It moved at lightning speed—no, faster than that; it seemed to teleport from place to place.

SLASH! SLASH! SLASH! SLASH!

The slashing attacks ultimately struck the demons behind the spherical demon, cutting hundreds down and reducing them to ashes one after another.

However, the spherical demon itself was never hit. Its long tongue extended further until it wrapped around one of the armament’s arms.

“That monster! Can it teleport?!” Song wondered. “Mother, be careful!”

Song rushed to help, but it was too late. The creature dragged the arm forward and devoured it instantly.

“GULP…!”

“Bastard, you think you can eat anything?!”

The Heavenly Empress was more irritated than usual this time—perhaps because of everything she had endured throughout this long, exhausting day.

“BURP.”

As the creature burped, a huge black tumor suddenly grew on its left side. She attacked it immediately while it began to transform; her five remaining arms tried to slice through its body.

Yet it moved incredibly fast—so fast it seemed to teleport! As it shifted, the large tumor on its left side rapidly grew longer and larger until…

It became a massive arm of black steel, with five long fingers gripping a huge sword of light and darkness…

“I-It copied my Imperial Armament?!”

As the Heavenly Empress reeled from the monster’s bizarre powers, Song reached them and attacked with everything he had.

A pseudo-domain of Heavenly Light and Darkness embodying Yin and Yang manifested around his body as his long wings spread out beautifully.

He combined the Essence of Heaven and Earth with Yin and Yang seamlessly, forming a huge sphere of pure harmony.

“HAAAAH!”

Song roared and launched it at the spherical demon, which swiftly swung its large arm and tried to grab the sphere and eat it!

CLANG!

As it brought the sphere to its mouth…

“Fool.”

BOOOMMM!!!

The spherical demon’s eye widened. The explosion—unleashed through Song’s [Divine Domain of White and Black Heaven’s Balance] Skill—engulfed it completely.

It could no longer “teleport” as before. Song’s attack had created a pseudo-domain that twisted space around it, forming an invisible bubble trapping the sphere.

He had deliberately baited it into trying to eat the sphere—knowing it devoured anything it saw!

The result?

“G-GGGHH…”

The creature emitted a strange, pained sound as its external body shattered like glass. Pieces of black glass-like material fell away, revealing a strange interior of gooey miasma and red blood.

Its eye had exploded, leaving a huge hole where it once was, constantly burning with deadly flames of Light and Darkness.

“Did you actually expect that we would be easy prey?! Mom! Let’s kill it quickly!”

“On it!”

As mother and son charged into battle, the spherical demon opened its jaws, revealing its long red tongue—now turned black and white…

FLUOSH!

From within, a small sphere of light and darkness manifested, copying Song’s technique in an instant.

“It copied my…?!”

BOOOMMM!!!

The sphere of light reached mother and son in a second, unleashing a massive explosion—not as large as Song’s, but powerful enough to send them flying with bruises and bleeding wounds across their feathers and skin.

“…”

The eyeless spherical demon continued overflowing with cosmic demonic energy granted by its Avatar. It quickly manifested dozens of these spheres, which began rotating around its body.

“I can’t believe it copied my ability so easily. So it ate it even when it damaged it?!” Song wondered as his mother covered him with her Healing Flames of Hope.

“It seems to be a rather tricky enemy to deal with…” the Heavenly Empress said, her heart pounding faster and faster. “But I believe we can beat it, as long as we synchronize our strength and fight as one, my son.”

“As one?” Song wondered. “H-How do I do that, Mother?”

“It’s easy,” the Heavenly Empress said, glancing at Anna’s Egos. “Would you two help us out?”

The Egos looked at each other. They had been about to join the battle but knew they were quite frail. One or two blows from a foe as strong as that Spherical Demon could easily kill an Ego. They had planned on long-range attacks.

However, the Heavenly Empress’s idea seemed far better.

“Oh, I see what you’re trying to do, Master,” Yin nodded. “Very well.”

“We’ll also lend you a part of our power,” Necro said. “So use it well!”

The two Egos rushed toward Song and the Heavenly Empress. Their bodies turned completely ethereal and wrapped around the pair.

At the same time, dozens of spheres of blinding harmony rushed toward them, smaller versions of Song’s attack, but conjured dozens of times over, making them ultimately even more threatening!

“…”

The spherical demon had no eye left to see, but its cosmic demonic aura senses easily patrolled its surroundings, searching for their location.

“BLEHEHEH…!”

It ultimately located the two powerful presences right behind it, laughing viciously.

The spheres of harmony surged forward in a gigantic bombardment of explosions that engulfed mother and son!

BOOOM! BOOOM! BOOOM! BOOOM!

Yet amidst each explosion, the two presences moved rapidly, evading the deadly light and darkness that had achieved complete harmony.

Then, piercing through the clouds of smoke, they appeared before the spherical demon—mother and son now clad in bright armor of rainbow colors, overflowing with Anna’s power.

“…!”

The Spherical Demon panicked. It attempted teleportation again, appearing several meters away and preparing another barrage.

And yet…

“…?!”

Its senses sharpened as panic surged. It noticed one of them had reached it in an instant, flying precisely to where it planned to teleport, as if predicting its trajectory.

“Don’t think that will work anymore!”

With a downward kick, he pierced straight through the demon’s body, leaving a gaping hole and sending it crashing into the seas below.

CRAAASH!

“Well done, Song! It worked as I thought.”

Yin’s voice echoed in Song’s mind.

“Indeed, it did, Anna!”

What they had done was simple: the Egos transformed into powerful armor over mother and son and shared their powers.

By channeling and controlling Song’s remarkable abilities, Anna expanded an invisible pseudo-domain across the skies, covering a wide area.

It allowed Song to pinpoint exactly where his foe would teleport by sensing the wavelengths of demonic energy and mana.

Yes, the spherical demon truly teleported—by sending a signal of demonic energy to a chosen spot, then letting that signal tear into space and pull it there instantly.

It was a rudimentary method developed by this demon species, specifically suited to their original habitat.

And because of it, Anna could predict its trajectory!

“GRRHH…!”

The Spherical Demon groaned angrily. It spun in midair, halting its fall and glaring at Song above the skies.

All this time it had been trying to regenerate its wounds—yet it could not. Strange energies—Ki—infected it and halted regeneration. The monster struggled.

It spread its tongue across its body, licking its wounds and attempting to consume the blocking energies while summoning more Spheres of Harmony.

However…

“{Heavenly Sword of Hope}!”

FLAAASH!

A huge sword of golden flames manifested out of nowhere, striking from beneath the sphere. Its eye widened as it tried to teleport away quickly.

Only for Song to meet it with a pair of swords of his own, crafted from black bones of darkness and white bones of light, conjured and assembled by Necro, who had bestowed them upon him.

“{Radiant Sword of Harmonious Death}!”

Song swung his blades. The spherical demon fired its Spheres of Harmony against them. Several explosions engulfed the swords, but they continued rushing forward. Two gigantic slicing waves were about to strike!

SLAAASH! SLAAASH!

The demon opened its jaws, preparing to devour both slicing waves while firing a giant beam of demonic cosmic energy from its empty eye socket, but…

“GRYACK?!”

The monster could not devour them as intended. The potency of the slashes severed its tongue, and the beam it fired was effortlessly deflected by the Heavenly Empress’s Sword of Light!

BOOM! BOOM! BOOM! BOOM!

As countless explosions reverberated through the frenetic battle, Song appeared behind the monster as it tried to evade his mother’s slash. The creature quickly manifested dozens of huge arms made of black metal, layered with even more armor forged from Harmony!

“It’s combining the powers seamlessly?!”

As Song realized this, he swiftly activated the Cursed Seals within his armor—formed by Yin’s ethereal presence—and overflowed with emotions of Hatred, Wrath, and Sorrow.

“{Freezing Flames of Wrathful Sorrow}! {Infernal Winter of Hatred}!”

By combining the elements, cursed seals, and his own powers, Song unleashed an explosion of freezing flames that suddenly slowed the dozens of metallic arms. At the same time, he summoned a powerful snowstorm that enveloped and froze them further—until the ice turned red and detonated, melting the metallic arms!

BOOM! BOOM! BOOM! BOOM!

“GRAGH?!”

The spherical demon was left speechless. Only for the Heavenly Empress to appear behind it. The creature desperately opened its jaws, summoning something from within!

Then, another crimson eye emerged from the interior of its mouth as relentless, eternal darkness spread everywhere, engulfing both Song and his mother.

“Careful! This is Void! The demon is trying to devour you both by exposing its own stomach!”

As Yin screamed a warning, the Heavenly Empress and Song resisted the Void’s power, unleashing their powerful Auras and spreading them wide.

FLASH!

“This Void…! Its power is tremendous! What in the world is this thing?!”

As the Heavenly Empress began to be dragged toward the demon’s maws, her aura and armor merged into one.

“{Heavenly Graveyard of Demonic Spirits}!”

Necro’s power fused with the Heavenly Empress’s power of Hope, summoning a horde of nearly a thousand demons formed from the souls of the demons killed earlier. The massive swarm surged toward every angle, tearing apart the Void through sheer volume.

“GUGH?!”

The spherical demon forced its Void to consume them, rapidly devouring the demonic undead one by one!

However…

“If all you want is to eat, then eat! Eat as much as you want!!!”

Song screamed furiously. The powers of Yin’s Demonic Cursed Seals made his abilities unstable yet even more potent.

Through his [Divine Dao Child of Fate Aura] Skill, Song unleashed his powers at maximum, releasing an aura of darkness and light that encompassed everything!

FLASH!

“GAAAGHH?!”

The giant sphere began devouring countless amounts of light and darkness. The Void started to inflate rapidly—its stomach reaching its limit in mere seconds.

It could only eat techniques one bite at a time—but this?!

It was too much!

“Song, wait, you’re going to…!”

Anna tried to stop him from such reckless action.

But it was too late.

BOOOMMM!!!

The Void Stomach of the Spherical Demon erupted, exploding and blanketing the skies in darkness.

Space shattered and fractured. Any nearby demons that glimpsed the approaching Void began fleeing in terror.

But it was too late—they were consumed as well.

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