The red sands of Mars stretched endlessly into the horizon, an unbroken expanse of desolation and silence.

To the casual observer, it might have seemed lifeless---another barren, hostile world unsuited to sustain life. But beneath the surface, nestled in the subterranean caverns and crevices, life thrived.

Not human life, but something older, more alien---creatures that had adapted to the harsh conditions over millennia.

These creatures, the Athkiri, had once ruled the underground of Mars, building intricate cities from the mineral-rich crust and surviving off geothermal energy.

Their bodies were perfectly suited for the planet's atmosphere---thin, cold, and unbreathable by human standards. The Athkiri had no use for oxygen.

But that was before the virus.

The humans arrived on Mars a century ago, seeking refuge from the ecological collapse on Earth. With them, they brought their machines, their technology, and, unwittingly, a virus.

It spread like wildfire through the Martian ecosystem, infecting not just the Athkiri but other native species as well. At first, the symptoms seemed mild---a change in skin texture, slight behavioral shifts.

But then the transformations began.

The virus, it seemed, had one horrifying effect: it was turning the Athkiri into humans. Not entirely, not at once, but piece by piece, their bodies began to morph. At first, an arm, then a leg, then their lungs.

As the changes progressed, they found themselves suffocating in Mars' thin atmosphere. Their new human-like lungs needed oxygen, but Mars couldn't provide it.

They were dying.

Fast.

Sela crouched in the entrance of a narrow cave, her four eyes scanning the horizon for any sign of movement. She could feel the pressure building in her chest---the transformation had begun to take hold.

Her arm had already shifted, its once sleek, dark scales replaced by pale, soft human skin. Her fingers trembled as she flexed them, trying to hold on to her alien form. But she knew it was only a matter of time.

Behind her, the others waited in silence, their bodies at various stages of the transformation. They had taken to hiding in the caverns, away from the human settlements, away from the labs where their kind were being taken and experimented on.

The humans didn't understand what was happening, didn't realize the virus was their doing. They thought the Athkiri were simply mutating, becoming more like them. Some even saw it as progress.

But to Sela and her kin, it was a death sentence.

She had heard stories of what happened to those who fully transformed---how their bodies collapsed, unable to survive in the thin Martian air. The lucky ones died quickly, but others… others suffered, gasping for breath until their hearts finally gave out.

"We can't keep hiding," a voice said from behind her. It was Orin, his voice strained with pain. He had lost his ability to breathe in Mars' atmosphere two days ago and now relied on a stolen human oxygen tank to survive. But even that was running out.

"What choice do we have?" Sela replied, not turning to face him. She didn’t want to see how much of him had changed.

Orin let out a bitter laugh. "We could go to them. The humans. Maybe they can help us."

"They don't want to help us," Sela snapped. "They don't even know what they’ve done."

She had seen the human cities from a distance, the domes they had built to keep the oxygen-rich air contained. She had seen their labs, where they took Athkiri---those who were too far gone in the transformation---and studied them like lab animals.

To the humans, this was a scientific mystery to be solved, not a catastrophe.

Orin fell silent, but Sela could feel his desperation. They were all desperate. Every day, more of their kind succumbed to the virus. Every day, more of them became… human.

Sela stood, her legs shaky beneath her. The ground felt different now, strange under her new human-like skin. She couldn't feel the vibrations of Mars' heartbeat the way she used to. It was like she was losing her connection to the planet that had always been her home.

"We need to find a cure," she said softly, more to herself than to Orin. "There has to be a way to stop this."

"There isn't," Orin replied, his voice hollow. "We're dying, Sela. One by one."

She turned to him then, finally meeting his gaze. His once vibrant black eyes had dulled, turning a sickly shade of brown. His skin, now almost entirely human, was pale and fragile, and his breath came in shallow, labored gasps. He looked more human than Athkiri now, and it broke her heart.

But she couldn't give up. She wouldn't.

Sela straightened, squaring her shoulders. "I'm going to the human city."

Orin stared at her, stunned. "What? You can't---"

"I don't have a choice," she cut him off. "If we stay here, we die. If I go to them, maybe---just maybe---I can find something. A cure, or a way to stop the transformation."

"You're walking into their hands," Orin said, his voice rising in panic. "They'll experiment on you, Sela. They'll cut you open to see what's happening inside you."

"I know," she said quietly. "But I'm already changing. I don't have much time left."

Orin didn't argue further. There was nothing left to say. They both knew what was at stake.

Without another word, Sela turned and began the long trek toward the nearest human city. Each step felt heavier than the last, the transformation sapping her strength. Her human-like arm was weak and awkward, her muscles clumsy and unfamiliar. She stumbled several times, but forced herself to keep going.

The human city, named New Terra, loomed on the horizon---its great glass dome glittering in the weak Martian sunlight. It was a marvel of human engineering, a testament to their determination to survive on a planet that wasn't theirs. Inside, they lived in comfort, breathing air rich with oxygen, their bodies thriving in an artificial atmosphere.

To Sela, it looked like a prison.

As she approached the city’s outer perimeter, she kept to the shadows, avoiding the automated drones that patrolled the area. She knew the humans didn't trust the Athkiri. They saw them as threats, dangerous creatures from another world. If they caught her, they wouldn't hesitate to detain her.

But she had no other option.

Her heart pounded in her chest as she slipped through a breach in the city’s outer wall---an area where a mining drill had malfunctioned weeks ago.

She squeezed through the opening, her body trembling with exhaustion. Inside the dome, the air was thick and humid, a stark contrast to the dry, cold atmosphere outside.

She stumbled forward, her vision swimming. She could feel her lungs struggling to adjust, the transformation accelerating now that she was inside the human city. Her body craved the oxygen, but it also rejected it, confused by the conflicting signals it was receiving.

Sela collapsed to her knees, gasping for breath.

"Hey!" a voice shouted from nearby. "Are you okay?"

She looked up, her vision blurry, to see a human standing over her. He was young, with dark hair and wide eyes filled with concern. He reached out to help her, but froze when he saw her arm---half Athkiri, half human.

"Oh my god," he whispered, backing away. "You’re one of them."

"Please," Sela rasped, her voice weak. "I need… help."

The human hesitated for a moment, torn between fear and compassion. Then, with a shaky breath, he knelt beside her and pulled a small device from his belt---a portable oxygen tank. He placed the mask over her face, and she inhaled deeply, the rush of oxygen filling her lungs.

For a moment, the relief was overwhelming.

But it was short-lived.

The transformation wasn't just physical. It was changing her on a cellular level, rewriting her DNA. No amount of oxygen could stop what was happening inside her.

"You need to come with me," the human said, his voice urgent. "We have a lab---doctors who can help you."

Sela shook her head, her body trembling. "No… no lab. Just… cure."

The human looked at her, confused. "What cure? We don't---"

"Your virus," she gasped, her vision fading. "Your people… did this to us."

The human's eyes widened in horror as he realized what she was saying. "No… no, that's not possible."

But it was.

And deep down, he knew it.

As darkness crept in at the edges of her vision, Sela could feel her body failing. The transformation was nearly complete. She was more human than Athkiri now, and soon, she would die like all the others.

But as her consciousness faded, she held on to one last thought: even if she didn't survive, someone had to know the truth. Someone had to stop the virus before it wiped out her entire species.

With a final, shuddering breath, Sela closed her eyes, her body going still.

The young man knelt beside Sela's lifeless form, his hands trembling as he removed the oxygen mask from her face. The weight of what he had just witnessed settled heavily on his chest.

His mind raced with a thousand questions.

How could this have happened?

How could humans have unknowingly brought destruction upon an entire species?

He stared at Sela's body, now more human than alien, and guilt gnawed at him.

"We did this," he whispered to himself, his voice barely audible. XWe killed them."

Footsteps echoed in the distance, drawing closer. His heart leapt into his throat as he realized the security drones were likely coming, alerted by his movement near the breach in the wall.

Panic surged through him.

If they found him here with Sela, they would take her body to the labs. They would dissect her, study her, and her death would be nothing more than another data point in their research. They would never see her as he did now---a victim of their own carelessness.

He had to act fast.

He gently lifted Sela's body, her frail human-like form far lighter than he expected. With each step, the weight of responsibility grew heavier in his mind. He couldn't let the truth die with her.

If the virus had transformed Sela and the other Athkiri, it meant it could still be stopped. There had to be a way to undo the damage humans had done to this world.

The nearest lab was just a few blocks away, hidden in the heart of New Terra. But he couldn't take her there. They wouldn't listen to him. They would dismiss his concerns, wrap it in red tape, and continue their experiments.

Instead, he knew where he needed to go: the undercity, where the resistance lived.

The undercity was a place few dared to venture. It was home to those who had grown disillusioned with the human colony on Mars. Scientists, engineers, and activists who believed humanity had no right to terraform and exploit another world.

They had been branded as radicals by the government, but now, with Sela's body in his arms, the young man realized they might be the only ones who could help.

He hurried through the alleyways, avoiding the patrols and security checkpoints that dotted the city. His breath came in ragged gasps, and he could feel his heart pounding in his chest. He didn't have much time before someone noticed the breach in the wall.

After what felt like an eternity, he reached the entrance to the undercity---an old, abandoned mining shaft that had been converted into a hidden community.

He tapped a sequence of numbers into the control panel, and the metal doors slid open with a hiss. As he descended into the darkness, the cool air of the underground hit him, a stark contrast to the humid atmosphere above.

The undercity was dimly lit, with makeshift homes and shops built into the walls of the cavern. People milled about, their faces marked with the same exhaustion and frustration he felt. But these weren't people who had given up---they were fighters, driven by a deep sense of justice.

He made his way to the far end of the cavern, where the resistance leaders held their meetings. They would know what to do.

As he approached the meeting hall, he was stopped by a guard---a tall, imposing woman with a stern expression. Her eyes narrowed as she saw Sela's body in his arms.

"What is that?" she demanded, her hand resting on the hilt of a blaster at her side.

"She's… she's an Athkiri," the young man stammered, his voice shaky. "Or she was. The virus… it's turning them into humans. And it's killing them."

The guard's eyes widened in shock, and for a moment, she seemed unsure of what to do. Then, without a word, she stepped aside, motioning for him to enter.

Inside the meeting hall, a group of people sat around a long table, deep in discussion. At the head of the table sat Dr. Lysandra Mallory, one of the most brilliant scientists on Mars and the leader of the resistance. She looked up as the young man entered, her eyes sharp and calculating.

"What's going on?" she asked, her gaze falling on Sela’s body. "Who is this?"

The young man swallowed hard, feeling the weight of the moment. "This is Sela," he said. "She was one of the Athkiri, but the virus… it's turning them into humans. I think we brought the virus with us when we came to Mars. It's killing them."

A heavy silence fell over the room as the others processed his words. Dr. Mallory rose from her seat and approached him, her eyes studying Sela's lifeless form.

"Put her on the table," she instructed, her voice calm but laced with urgency.

The young man carefully laid Sela’s body on the table, stepping back as Dr. Mallory and her team of scientists began examining her. They moved quickly, running scans and tests, their faces growing more grim with each passing moment.

"This is worse than we thought," one of the scientists muttered under his breath. "The virus isn't just transforming them---it's rewriting their DNA, turning them into humans at a molecular level."

"And once they're fully human, they can't survive in the Martian atmosphere," Dr. Mallory added, her voice heavy with sorrow. "It's a death sentence."

The young man felt a lump form in his throat. "Is there anything we can do? Can we stop the virus?"

Dr. Mallory looked up from her work, her expression grave. "We'll do everything we can. But this virus… it:s unlike anything we've seen before. It's adapting faster than we can study it."

She paused, her eyes flicking to Sela's body. "But if we can figure out how it works, we might be able to develop a cure."

Hope flickered in the young man's chest. "You think you can save them?"

Dr. Mallory sighed, her gaze softening. "I don't know. But we have to try."

Over the next several days, the resistance scientists worked tirelessly to unravel the mystery of the virus. They studied Sela's body, tracing the transformation from Athkiri to human, searching for a way to halt the process.

The young man stayed by their side, helping wherever he could, driven by the guilt of what humanity had done to the Athkiri.

It wasn't long before they made a breakthrough.

"The virus was engineered," Dr. Mallory said one evening, her voice filled with both triumph and horror. "It was designed to target the Athkiri specifically, to transform them into humans. But it's mutating, evolving faster than we anticipated. Whoever created this… they knew exactly what they were doing."

The room fell silent as the implications sank in. This wasn't an accident. The virus had been created intentionally---likely by the very same scientists who had come to Mars to terraform the planet.

Perhaps they saw the Athkiri as obstacles to human colonization, or perhaps they believed turning them human would allow them to coexist more easily. Whatever the reason, it was clear that humanity had brought this disaster upon the Athkiri.

"Can we stop it?" the young man asked, his voice barely above a whisper.

Dr. Mallory hesitated. "We've developed a prototype of a cure. It's risky, and we're not sure if it will reverse the transformation, but it should stop the virus from spreading further."

The young man felt a surge of hope. "Then we have to distribute it. We have to save them."

Dr. Mallory nodded. "We will. But we need to act fast. Every day, more of the Athkiri are dying."

With the cure in hand, the resistance prepared to leave the undercity. They would travel to the hidden Athkiri settlements, distributing the cure and doing everything in their power to save the remaining survivors.

The young man stood at the entrance to the undercity, watching as the resistance members loaded up their supplies. He had done everything he could, but the weight of his guilt still lingered. He couldn't forget Sela's face, her final words echoing in his mind.

"Your people… did this."

He knew that humanity would have to answer for what they had done, but for now, all that mattered was saving the Athkiri.

As the resistance set off toward the settlements, the young man couldn't shake the feeling that this was only the beginning. The virus might be stopped, but the damage had already been done. Mars would never be the same again.

And neither would he.

***

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