The rover hummed softly as it moved across the red expanse, its wheels leaving long tracks in the fine Martian dust. Inside, silence filled the cabin except for the occasional creak of metal and the faint hiss of the oxygen filters.
Eris sat by the window, watching the endless dunes glide by. The light from the distant spire was still visible even now, flickering like a star on the horizon. He could feel it in his chest — not painful this time, but constant, like the steady beat of a second heart.
Jonas was driving, eyes fixed ahead, hands firm on the control sticks. "We've been running for hours," he muttered. "Navigation's unstable. Magnetic drift is throwing off the compass — again."
"Keep heading north," Selene said, scanning a holographic map projected in her palm. "If my calculations are right, we're within range of the Valles Marineris comm tower in two sols."
Liora sat beside Eris, her voice soft. "Do you think they know what happened back there? The base, I mean."
Jonas scoffed. "If they don't, they will soon. That energy surge was visible from orbit."
No one laughed.
The silence that followed was heavy, broken only when Mara passed a ration pack to Eris. "Eat," she said quietly. "You've barely had anything since the collapse."
He looked down, realizing she was right. His hands trembled slightly as he unwrapped the pack, the silver light beneath his skin pulsing in slow rhythm.
Selene glanced at him. "It's stabilizing," she noted. "That's good. The resonance is less aggressive now."
Eris looked at her, confused. "Resonance?"
"The connection between you and the Heart," Selene said. "When you bonded with it, it imprinted your genetic signature. It's not just calling you anymore, Eris. It's adapting — aligning its frequency with yours."
Mara frowned. "That sounds like it's evolving."
Selene nodded grimly. "Exactly."
The rover jolted suddenly, throwing everyone slightly forward. Jonas cursed and slammed the brake. "What now—?"
Outside, the ground had changed. The flat plain gave way to sharp ridges of dark stone — unnatural formations that hadn't existed on any of their maps. They pulsed faintly, like veins of molten iron, glowing in rhythmic patterns that matched Eris's heartbeat.
Liora's breath hitched. "Oh no…"
Selene stepped out first, her boots sinking into the dust. The air around the ridge shimmered faintly, warping light. She knelt and touched one of the glowing lines. "This isn't geological. It's energy. The Heart is reshaping the planet."
Jonas grabbed his scanner and waved it toward the nearest ridge. The display flickered violently, then shut off entirely. "EMP interference. It's everywhere."
Eris climbed out of the rover and approached the glowing stone. The closer he got, the brighter it pulsed. The light beneath his skin flared in response, his chest burning with heat.
"Eris, stop!" Mara called out.
But it was too late. The ridge split open with a sudden hiss, revealing a deep fissure beneath it. A wave of heat rolled out — and then a faint whisper, so soft it was almost imagined.
"Return… to the cradle…"
Eris froze, eyes wide. "It's speaking again."
Selene moved quickly, pulling him back. "That wasn't the Heart. That was something else."
Jonas frowned. "Something else? You mean there's more of them?"
Selene looked at the fissure, her face pale. "The Heart isn't alone. If Mars was built as a prison… then there are others — chained deeper."
The wind howled through the broken ridges. Dust lifted, swirling into thin, ghostly forms before dispersing again.
Mara shivered. "We shouldn't stay here."
"No," Selene said. "We keep moving. Whatever's down there — it's not meant to see the light."
They climbed back into the rover, the tension hanging thick in the air. The vehicle began to roll forward again, its headlights cutting through the red haze.
Eris leaned back in his seat, breathing hard. His voice was quiet, almost trembling. "If there are more Hearts… then maybe that's what it wants. To wake them all."
Selene didn't answer. She just looked toward the horizon where the distant beam still shimmered faintly.
"Then we'd better pray," she murmured, "that we reach the northern base before it finds another."
Outside, Mars groaned — a deep, echoing rumble that came from beneath the surface, like something vast shifting in its sleep.