Maro pressed his fingers against the cool, smooth surface of the tetrahedron Traveler, feeling its pulse hum beneath his skin. The alleyway behind Rue Chartres was deserted, save for the gentle flicker of a neon sign reflecting off damp cobblestones. He had followed the frequency for hours, the vibrations leading him here like whispers in the wind.

The portal was unstable. That much was clear.

He adjusted the tuning fork pendant around his neck, a personal amplifier for his power. Harmonic resonance had always been his gift—an ability to manipulate sound frequencies, creating reverberations through matter and even thought itself. It was how he first discovered portals, how he learned to step through the world in ways few others could.

Tonight, however, the resonance was wrong.

A distortion pulsed through the Traveler’s frame, its frequencies fluctuating between order and chaos. Someone had left it open, either by mistake or by intention, and now the portal threatened to unravel.

Then, the message came.

A voice, barely perceptible, vibrated through the structure. It wasn’t sound in the traditional sense—it was something deeper, more profound. A Thought Trail left behind.

"Maro. The path is broken. We are lost. Find us."

The signature of the speaker sent a chill through him. He knew that mind.

Kailani.

She had vanished two years ago after attempting to map an unstable node in the Manta Network. Most assumed she had simply faded into some unreachable corner of the Sub-Side, her presence scattered among the echoes of failed portals. But now, her voice resonated through the tetrahedron, distorted and desperate.

Maro inhaled deeply, centering himself.

He struck the tuning fork against the Traveler’s frame. The sound it produced was clear, but not quite right. He adjusted his stance, angling his body to match the frequency’s flow, then struck again. This time, the sound elongated, stretching into something richer, deeper. The portal shimmered in response, its edges stabilizing.

He stepped through.

—

The Sub-Side was always disorienting at first. Maro emerged into a space that defied logic—a vast, infinite expanse where thought shaped reality. Floating geodesic shapes pulsed in the distance, the telltale markers of other portals overlapping like echoes in a canyon.

Kailani’s trail was here, but fragmented. Pieces of her presence clung to the space, flickering in and out like a weak signal.

Maro closed his eyes, extending his senses.

Harmonic resonance wasn’t just about sound—it was about intention, about finding the right frequency to bridge gaps. He let his mind attune to the scattered fragments, humming softly, his voice weaving through the currents of Sub-Side.

The echoes responded.

Images formed—Kailani trapped within a collapsing Thought Trail, unable to step forward or back. A miscalculated portal jump had locked her in a cycle of distortion. If Maro didn’t act soon, she would be lost for good.

He placed his hands on the nearest tetrahedron, aligning his breath with its vibration. The resonance had to be perfect—too sharp, and the portal would shatter; too soft, and it would close without retrieving her.

With a final exhale, he struck the tuning fork one last time.

The space around him trembled.

A rush of sound—voices, memories, the hum of infinite frequencies colliding—filled the void. The portal pulsed violently, then stabilized.

And then, Kailani stepped through.

Her expression was one of shock, then relief. “Maro…” she breathed.

He caught her before she collapsed, the strain of her long entrapment evident in her trembling form. The portal behind them flickered once, then sealed shut, its purpose fulfilled.

They were back in the alleyway. The neon light cast long shadows as Kailani steadied herself.

“You found me,” she said.

Maro smiled, his fingers still buzzing from the resonance. “I always find the echoes.”

The portal was gone. The Thought Trail had closed. But something told him this wasn’t the last unstable frequency he would have to face.

Not by a long shot.