A week ago

'There is only one way for you to wield your unstable magic,' said the girl with the multicolor hair. 'But you must understand the true essence of Mana and Magic.'

Rem looked at the girl as the wind blew by melancholically.

'Magic is like a seed in your heart. Your world view and experience nourish that seed and define its development. Using that description, Mana is the sunlight germinating and growing the tree of Magic. Abilities and skills would be the animals relying on that tree as its habitat. This relationship is the secret to the power of the multiverse. Rem, your ecosystem have mutated due to your emotional instability and created unstable energy that couldn't activate [Arrival of Dream]. To activate your abilities, you must get power directly from the sun.'

"You mean Mana, " Rem replied soberly.

'No, Mana is the sunlight. What I mean is that you have to access the star itself.'

The girl spread her hand and conjured the image of the cosmos.

'Every mana originated from the Center Force, the power of just, and Malice, the entirely of depravity. Every world-view--no matter how uncanny--lies between the two. Their continual grinding creates Mana and replenishes the flow of the great stream.'

The girl looked at Rem.

'Oh my master, if you desire power, the sun of the Center Force welcomes your contract as the queen's champions. However, even her majesty lack the experience needs to save you from our ultimate price.'

The girl's eyes glowed.

'Center Force is ancient and brutal. Before the queen's time, we are the heavenly punishment of the wick. We are the executioner of justice, governor of the law of karma in the name of the greater good. There is no redemption for evil in our eyes. We have no time for such mercy n this holy war. If the sacrifice has to be made to uphold justice, then it must be done. Now, do you know what a contract with us entitles?'

Rem nodded.

To use his power, he had to become their serf.

...

'In a decade, things might change under our queen's new policy, but for now, even she can't curb Center Force's brutality,' said the girl, looking at the portal of light glaring before them.

Rem looked into the cruel glow.

He shouldn't find this strange.

For most of its life, good is an interchangeable concept dictated by the victor. Base on this, the Pre-Satholia Center-force would be a vicious power to punish evil and discourage wickedness. It was only when humanity and mercy got added to the action that good and justice ceased to be an excuse for slaughter.

"When I make contact with that thing, I will become its slave, right?"

The girl nodded.

'The encroachment will happen slowly,' the girl shuddered. 'You will gradually lose your self-control and humanity as the Center Force consumes you. Moreover, the Center Force will continuously attempt to hijack your body for the elimination of evil. Even death won't release you from this contract. You will spend all of the eternities as an unfeeling tool to preserve the Center Force's justice. There will be no peace or closure for you ever again."

"So it is becoming a war-slave for eternity, " Rem resolutely closed his eyes. "Do I have a chance to cheat the contract?"

'Unlikely, no miracle that can null the contract exist,' the girl shook her head before giving a tired smile. 'But again, even the Center Force did not predict her highness's ascension. All-mighty doesn't translate to all-knowing.'

Rem nodded, silently making his resolve and marched forward with his eyes closed. He was afraid, but if he did nothing, death would be inevitable. That would be an absolute defeat, and he would never accept defeat.

Rem blindly walked into the light and touched the radiance.

It was a gamble staking 100% chance of death for two innocent girls against 99.99% prospect for a fate worse than demise for himself.

Rem made resolved, but still, he was disappointed. 

Unlike Superman, mere humans like him didn't have the power to fix things in the blink of an eye. Instead, what he got is a convoluted path up the hill.

Rem made his resolve.

The black sky of that world shattered, bathed in a clash of inhuman power against the grim determination of humanity.

It was doing the right no matter what the cost--not the power--that was the proof of a hero.

'It will be an honor to serve you, Knight of Satholia,' the girl knelt.

 'I-- Central--deemed Sir Remus Breaker as our commander worthy of his station. Every agent of Center Force is yours to command.'

...

From Cytortia's perspective, Rem was standing powerlessly in front of the charging army. A tide of massive, brutal beasts surrounded them. The imminent ending was bleak and inevitable.

Then something changed. A light of dreams came torn that destiny asunder. The magical glow shone in a column, creating a lighthouse of hope in that see inevitability.

Cytortia felt the boy running to meet the small army. She felt great sadness from him, but also an undefeatable determination.

Sandstorm curled around the boy. A strand of white tainted his bark-color hair. Cytortia even caught a glimpse of multicolor sunlight radiating from him. It almost reminded her of Tai Hua, but this wasn't just a display of might. An awe-inspiring embedded into the light. It was something no raw power could replicate.

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In that light, she saw a painting of sort. A girl who gave up hope and a caped man convincing her everything will be okay.

Cytortia frowned. That man must be a deity, but since when did a god radiate maturely.

Before she knew what was happening, the corrupted hoard charged at Rem only to meet a wall of sand. The sand swiped, drying the monster into desiccated corpses. Some unlucky beasts experienced got sanded down into skeletons. Even the tentacle sneaking from the toxic pond couldn't escape being mummified by Rem's sand. Cytortia gaped. How could this be real? Every step Rem took turned national threats into piles of dust. The bureaucrat in the Grand Empire would have a heart attack when they saw how Rem managed to outdo their two billion credit budget.

Then Cytortia got it.

In previous cases of Paracis Corrupter's arrival, it had taken root in the spring.

Rem concluded that the World Enemy was an extremely Hydrophilic plant; an arid condition would likely be lethal to it.

The goddess's eyes lit up. There was another exploitable weakness: the Paracis's reliance on natural Mana. 

Cytortia crouched down, using her abilities as a nature goddess a way she never did. The goddess stretched her power under the ground and tried to find any part of the waterfall that remains free from the Paracis's control.

She found something, but it was as small as a bean. Cytortia gritted her teeth. With all the effort she could muster, the girl reached into the reservoir and built the resistance into a bonfire.

On the waterfall, the Paracis Corrupter painfully jerked. Inside the monster, the horde Natural Mana went out of control as Cytortia stoke it up and disabled the Paracis's function.

The table started turning as the crippled hive-mind started dragging the army down. Combined the management crises with the sandstorm mowing down like weed, and it wouldn't surprise the massive army was now barely a shadow of what once was.

As for Luxinna, she managed to resist the sandstorm by ionizing the air with her lightning. However, the magically charged kick in the face from Rem sent her back where she started.

By then, it was already too late for the World Enemy.

Using 7-days of intense training and absolute elemental advantage, Rem destroyed a total of 115 corrupted monsters. It was a fight that barely took two minutes for the victor to stand clear.

In the end, only the corrupted Luxinna remained standing as a final opponent.

The Paracis cried as its death's bell started to ring.

...

Rem was winning, but he was also out of time.

His body was exhausted. A part of him pulled too much energy. Energies he couldn't afford to channel, and now every muscle in his body lodged a complaint letter in the form of crippling pain. 

'My lord, you are hitting your magical limit,' Central chimed in his head. 'Your magic will go into overheat if you continue... moreover.'

DIEEEEEEE!

Rem blurring eyes widened. What the heck is that?

'This will explain it better.'

A piece of information flashed through Rem's head.

[Desolate Blade

Rank: B

Ability: 

Sand-Mastery [S]

Dehydration [A]

Sand-Storm Protection [B]

????

Demerit: Demonic Erosion [A]

Origin: Legend of Asthur

Info: The Desolater Blade was created by the hero-king of Asthur, Ar'muskur, using one of the three beasts of the Ruined continent—the Beast of Sand. Despite killing it and sealing it's damaged soul into this blade, the demonic nature of the Beast remained ready to turn against its bearer.]

Rem glared at the yellow, jeweled encrusted dagger accusingly. Who the hell put it there? Who the heck tagged a demonic entity into the weapon he was using?

'You created this blade, my lord,' Central replied painfully. 'Six years ago, you thought it would be cool if your hero used a demonic sword just like in the cartoon you watched.'

Rem cursed. His eighth-grade syndrome came to screw him at the worst moment.

'Truth to be told, this is a blessing in disguise,' the exasperated voice of Central continued. 'While the erosion hampered your physical and mental vitality, it also lowered the Desolator Blade from [A] to [B] rank, allowing you to use it without dying from the recoil.'

Rem suddenly remembered his weapon's anti-army function. Could he use that to cheese this fight?

'Do you want to die?' Central uncharacteristically roared. 'Ya think ya can open fire with Anti-army attack at your pitiful power-level? You only have a [E] rank [Territory Creation]! That's the only one-meter range, you fool!'

One-meter range, Rem's heart sank. At this point, Rem was ready to believe the universe had a betting pool reserved for his head.

The berserked Luxinna let out a tremendous roared and launched her lightning-clad tentacles at Rem. The barrier of sandstorms received the truck slamming into a brick wall.

Rem gritted his teeth, but that previous two-minutes cost him too much. His eyes started to blur as his footsteps turned sloppy. Numbness invaded his body like a hammer cracking a nut. Worst of all was the pain from overexerting his power. It felt like someone was dipping his nerves in molten salt.

Luxinna's lightning broke Rem's defense a split second later and sent him sprawling. The deflected tentacles fiercely struck a tree nearby and lighted it on fires. In that orange glow, one thought shone across Rem's mind. He needs an opening. No matter what, the cure still sparkled in his hand like the hope for victory.

Rem got up as Luxinna launched another tentacle. He mistimed his dodging maneuver and got electricity coursing through his body. Luckily, he inched back enough to avoid the worse of the attack, but he still felt the sharp pain and sticky sensation shimmering across his chest.

The corrupted elf sensed the opportunity and acted on it. She pounced toward Rem like a tiger. It was a fast and ferocious attack that could qualify as a finishing blow.

 Rem was disappointed.

Had she retained her sanity and her mastery with the blade, his half-dead self wouldn't have a chance. The corrupted Luxinna didn't have any of those things. She was powerful but lacked grace and technique she originally had. She was faster but also more readable.

Rem clenched his teeth and wrapped the sandstorm around his short sword. Waves of sand interwove to create one-meter long chainsaw of desert and wind. With his muscle enchanted with his Magic, he swung the [Desolator Blade] up in a cross-counter.

In the background, the tug-of-war between the Paracis and Cytortia continued. Both sides looked at their respective champions with expectation. Meanwhile, flames began spreading from tree to tree, covering the battlefield in a ring of fire.

They clashed.

Although Luxinna was much stronger than Rem, his sword helped remedy that with greater reach. This fact was especially valid when she was caught wide opened in an all-out leaped.

The blade of sand landed a firm cut. Blood spurted from the wound, followed by a massive cry of pain. The elf was blasted backward and smashed down hard from the force. 

However, the ordeal was not over. The corrupted Luxinna got up--her blistered skin and tentacles were healing itself. With a growl, she threw another desperate bolt at Rem, but the sandstorm-blade parried that blast successfully. 

Unlike his previous defense, Rem focused all his defensive capability into a thin blade, raising its deflection ability to the point it could deflect the enhanced lightning.

Rem huffed. He was still at a disadvantage. Up the waterfall, the Paracis's main body started recovering from Cytortia's hacking. The flowery maw opened up, revealing a gaping hole that sprouted out a swarm of tentacles.

The boy grimaced. They were in a deep end. They need a way to take get inside Luxinna's offense range and then killed the corrupter.

Rem sighed tiredly. For once in his life, he was out of the idea.

'Rem, you still need to answer me for today's debacle. You aren't allowed to give up this easily, young man.'

Rem perked up. He knew that voice. Unlike the previous time he heard it, the current tone was more disapproving.

'Your majesty?' Central panicked. 'How can you be here?'

'Blame your master's idiotic action. Rem, my dear, I am pleased with your dedication, but this self-sacrifice is overboard. We need to talk over this later. But, for now, you must splash the poor girl with Cytortia's cure then stabs her with your weapon.'

That was the plan? Should it be that simple?

'We must establish a connection. Luxinna's mental state is too fragile for me to directly force my way in. We are lucky your Magic got linked with the Center Force. If you manage to connect your Magic into her body, I might be able to communicate with her and deal the finishing blow.'

Rem gritted his teeth. Assurance slowly replaced the desperation in his eyes.

Nothing motivated a person like hope.