The Protagonist's Sister Is Actually The Strongest

The Heavenly Empress glanced at her opponent after she noticed that the Heavenly Demon had changed and what he had become. Her foe was in shambles before her might, yet it was resilient as well, cosmic powers surging from within it, reforming its body and shape once more.

“It’s over.”

Her opponent, a small robot with a head resembling the planet Saturn, spoke with the voice of a child mocking her. Its bronze body glowed brightly beneath the sun. An aura of bronze absorbed all light within its surroundings, weakening her. It was confident of its power, or, well, it was made to be.

“It seems he’s alright,” she smiled. “But goodness, he really scared me there… This man, to think he would go so far to grow even stronger.”

“…”

The Venerable Machine seemed slightly offended that, despite the battle rapidly shifting towards its victory, she was ignoring it. The Constellation that had taken residence within the Venerable Machine fighting the Heavenly Empress was rapidly overtaking the robot; as they fought, it began to analyze her.

[The Cosmic Throne {Mother of Artificial Life} is analyzing you.]

“Hmm…”

She quickly gazed back at the machine as a gigantic aura of cosmic power surged from the robot, shaping and expanding into a massive Cosmic Domain.

FLUOSH!

“Oh?”

The sound of these powers and energies expanding across the skies reverberated as the Heavenly Empress sensed an immense surge of power coming from the robot.

“It seems you’ve finally come; I’ve grown tired of waiting for your arrival,” the Heavenly Empress smiled. “Mother of Artificial Life, you. I have a question. Were you the one that gave my son the Demon King Seed?”

“So it seems you were waiting for my descent?” laughed the robot, with a completely different, feminine voice. “How hilarious. You could barely hold your own against the Venerable Robot before! It was specifically made to kill you, you know? It doesn’t matter if the other was defeated; as long as one of you three can die, your entire operation will fall into pieces, and this world will eventually become ours.”

“Oh, I see…” The Heavenly Empress nodded. “You ignored my question. I will repeat it again. Did you—”

FLASH!

Before she could continue her words, the robot rushed towards her, growing larger, with bulkier arms overflowing with cosmic energy merged with heavenly ki, it unleashed a barrage of punches that absorbed the light on its surroundings and powered up the attack power and speed of its blows.

CLASH! CLASH! CLASH! CLASH!

Each blow was strong enough to crack open a cave through a mountain, and the Heavenly Empress was engulfed on them, hitting her chest, pelvis, shoulders, head, and legs constantly. Mostly targeting the joints, aiming to tear her limbs apart!

“I’ll kill you as quickly as possible!”

The Constellation’s voice echoed from the robot as the machine’s left arm overflowed with the light absorbed from the Heavenly Empress, becoming ten times as big, with propulsors releasing flames, increasing its movement speed and power as the massive metallic punch impacted the Heavenly Empress with all its might.

BOOOMM!!

An explosion of cosmic flames and heavenly light was unleashed at the moment of impact, spreading smoke everywhere.

“That must have at least dealt more damage… And with the Domain active, she cannot draw Hope Essence from the World,” the Constellation analyzed the situation. “Yes, as expected, my plan is working perfectly. My calculations are never wrong, after all.”

As the smoke dissipated, suddenly, the Constellation…

“Huh?”

Realized something: it could no longer feel its left arm anymore, the arm of the robot it was taking as a vessel.

The smoke dissipated by a powerful pressure emerging, as the body of the Heavenly Empress emerged amidst the black smoke; her body was tattered, but not destroyed; at best, there was some blood here and there.

But she didn’t look all that terrible, even more when she was carrying the giant arm from the robot.

“What?”

At some point, she had just torn it apart while the Constellation was completely concentrated on killing her!

It must have been such a quick move that the robot didn’t even notice until now.

“I believe there’s a misunderstanding, Constellation.”

Her words echoed across the entire Domain, as the Heavenly Empress Aura grew even stronger, spreading like a sea of golden light everywhere, completely overwriting the cosmic domain entirely!

“The Domain?!” The Constellation panicked. “You’re… impossible! How are you capable of overwriting my Domain?!”

“You truly believe I am as weak as I showed you to be?” the Heavenly Empress asked, her golden eyes glowing like two stars, her white feathers waving by the pressure created by her presence. “I oftentimes take my time fighting a foe, you see. I don’t even like showing a tenth of my power. I maintain it sealed, at all times.”

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“You maintain ALL your power sealed?!” the Constellation asked. “Hah… You must be bluffing! There’s no way a Mortal like you could ever—”

RUMBLE!

“Guh?!”

The Constellation suddenly felt a tremendous weight, as if a massive planet was weighing over her entire Cosmic Soul!

The Heavenly Empress looked down at the robot, which had been moving down more and more as she unleashed her power.

At this point, the intensity of her light was so strong she resembled a golden star itself, and it wasn’t just in appearance.

Like a star, her entire surroundings changed; her power carried such density that a gravitational force was generated around her.

“Not all, about 99.9% of it,” said the Heavenly Empress. “I do it because my power is dangerous… I could kill people without realizing. The Heavenly Demon never does this because he’s an unhinged berserk warrior; he doesn’t care about anything around him… or well, he didn’t before.”

“T-That’s…!” the Constellation’s robot gritted its metallic teeth, glaring at her with fury. “You’re just lying to buy time, aren’t you? Perhaps you took one arm, but so what?! Can you take on this entire powerful vessel? Even more as I evolve it to its ultimate form to fit my Cosmic Soul?!”

“Oh? Well, show me, be my guest,” the Heavenly Empress nodded. “Come with all your power. It wouldn’t be fair for you otherwise.”

“Y-You…! You’ll regret saying such things!”

RUMBLE!

The power of the Constellation descended, the Domain was once more overwritten, or well, half and half, a Domain Clash ensued, the power of the Heavenly Empress against the Mother of Artificial Life.

TRUUUMMM!!!

The Venerable Machine rapidly transformed, absorbing the powerful Cosmic Energies, it rapidly began to grow larger, growing hundreds of mechanical tentacles through its body and becoming much more streamlined, abandoning most of its humanoid appearance.

“What is that? You became a squid?”

The Venerable Machine was now over fifty meters in height, and its monstrous form could not even resemble its previous appearance, becoming a physical vessel of the Constellation completely, taking upon her Constellation Body appearance.

“A squid? Hardly. My body has evolved and improved to adapt to any situation and environment. My children, ever-growing and ever-expanding, have invaded over a hundred planets with this shape, which has proven to be effective.” The Constellation spoke.

“Interesting, are you done? Let’s begin,” the Heavenly Empress said, holding her sword tightly. “Show me what you got.”

“…Irritating, but I will gladly see your face after you realize your mistake,” the machine spoke, her tentacles rushing forward.

FLASH! FLASH! FLASH! FLASH!

Each tentacle was over six meters thick, carrying compressed metal plates and immense weight within them, further fueled by cosmic energy, strengthening its attack power and speed.

The tentacles rushed towards her, piercing through her barriers and shattering through space itself, as her Domain was warped and damaged, shockwaves being released across their surroundings.

CLASH! CLASH! CLASH! CLASH

However, she kept up.

Her movements became incredibly fast and precise, her sword overflowing with light, easily intercepting the incoming blows; sparks of electricity and holy light reverberated, and the robot’s tentacles began to rapidly bend over.

“This… is nothing.”

Her eyes overflowed with golden light as her wings spread out; thousands of feather projectiles were fired at once, engulfing the robot entirely; the tentacles that were hit instantly exploded into pieces.

BOOM! BOOM! BOOM! BOOM!

“Ngaah?!”

The Mother of Artificial Life was left speechless, her gigantic body being pushed back by the barrage of explosions, which seemed strong enough to pierce through her several layers of defenses.

“T-This cannot be… My calculations said that…!”

“Your calculations are simply wrong then.”

“Ah!”

The machine’s gigantic red eye widened as the Heavenly Empress appeared above it, her golden sword being swung down as a massive slashing wave was summoned, splitting the entire robot apart.

SLAAASH!

Forcefields were deployed, anti-gravity barriers, cosmic soul barriers, and even raw cosmic energy crystalized into metal and diamond-like materials to reinforce the machine body.

And yet…

CRAAASH!

It was still split apart, shattering into countless pieces right after that, as wires, circuits, and more blew up, scattering across the space of the Domain.

“It’s not…! Over yet!”

The Machine Constellation didn’t give up; her powers rapidly manifesting even more, the machine parts turned into a huge swarm of nanomachines, quickly fusing back into her form, healed completely.

“So you’re that type of robot, understood.”

The Heavenly Empress remained stoic and calm, resembling a robot more than her own opponent, who seemed overly emotional, perhaps a side effect of gaining a Soul after becoming a Constellation.

“DIE!”

The robot transformed, creating hundreds of massive cannons from its tentacles and firing several blue-colored beams against the Heavenly Empress at once!

“I suppose it’s time,” the Empress said, becoming more serious.

“{Heavenly Golden Flames of Hope Arts}: {Heavenly Golden Dragon Shield}”

FLUOOOSH!

Her flames gathered into a single point, materializing into a beautiful golden shield in a mere second and rapidly tanking the massive series of explosive beams at once.

BOOM! BOOM! BOOM! BOOM!

As this happened, she pushed forward, the shield rapidly absorbing the energies and then firing them back as a powerful golden breath of its own.

TRUUUM!

“NGUH?!”

The Machine Constellation was shocked, as the shield kept pushing forward; her cannons were beginning to overload; she couldn’t keep firing these attacks indefinitely!

“AARGH!”

Crack, crack…!

“T-This cannot be…! My calculations, once more, failed?!”

CRAAASH!

The cannons exploded into pieces one after another, disappearing entirely. The Heavenly Empress unleashed her shield’s power before it disappeared, as the dragon’s breath pierced through the Machine Constellation, leaving a gigantic hole through it!

BOOMMMM!!!

“AAAGGGH!”

The scream of agony from the Machine Constellation was heard, her Cosmic Soul taking massive damage, which the Heavenly Empress quickly used to rush forward, swinging her blade down and up, then to the right and left in quick succession, cutting and cleaving through hard metal plates, circuits, and wires.

SLASH! SLASH! SLASH! SLASH! SLASH!

“Dammit! Damn you!”

The Constellation screamed as her powers continued growing larger the more she descended, rapidly opening hundreds of blue portals around her out of nowhere.

“Come, my children! End her life!”

As she commanded, hundreds of smaller machines identical to her appeared everywhere, attacking and surrounding the Heavenly Empress.

“Hm, so this is your special ability, huh? Summoning, amazing.” She smiled, cutting through hundreds of smaller machines even if they were powered by cosmic energy as if it were nothing. “Now let me show you my special ability!”

Her left hand gathered her Flames of Hope and quickly began concentrating it within a single point, constantly making it stronger, more powerful.

Until…

“{Heavenly Golden Flames of Hope Arts}: {Radiant Nova}”

FLAAASH!

The bright golden light of the Heavens themselves encompassed everything, as the fiery flames of the Nova exploding consumed the robots, vaporizing them instantly.

BOOMMMM!!!

At the same time, the Mother of Artificial Life screamed, her army being completely obliterated with each passing second.

“W-What?! This is hopeless! I… I should retreat; it doesn’t matter anymore!”

She quickly began to pull back her Cosmic Soul while the Heavenly Empress was distracted fighting her children.

Her Cosmic Soul rushed outside, only for…

Something to stop her.

CRAAASH!

A massive mechanical arm smashed her Cosmic Soul back into the Domain, as the Constellation could swear she saw a brown-haired human right before she was struck down.

“T-That’s…!”

And then she appeared, entering the Domain unaffected, looking at the Constellation with a serious face.

“Did you think I was going to let you escape?”

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