Algae clogged the corridor like damp smoke, muffling every lamp-beam as Horizon Team slipped from the city's outer ring. I swam point, Rejah beside me, Veshra behind with a crate harness, and the Exile guide Echo-Hand closing the file. The sentry lamps above followed our progress, pale eyes tracking the masked outsider until reef shadows swallowed all light.
City currents faded into a heavy stillness. The deeper we pushed, the louder a thin whistle rang inside my inner-ear ridges, a tinnitus that pulsed exactly once for every heartbeat my pearl managed. Too much shaping earlier, I thought, forcing slow breaths. Push water gently, do not shear it.
"Ringing already?" Rejah whispered, sensing my hesitation.
"Every time I draw," I answered, pressing fingertips to the side of my helm. "I can manage."
Echo-Hand spoke for the first time since the launch. Their voice, muffled by barnacle-thread mask, carried a clipped accent I still could not place. "The caverns ahead stand quiet, but quiet does not mean empty. Stay within my wake and avoid the silt shelves."
Yera's orders echoed in my head: trust the guide, yet verify everything. I gestured agreement, and we slipped into the trench.
The silt canyon glowed weakly, but the light was wrong, stuttering in pockets as if someone dimmed a lantern with every other breath. Plumes of violet drizzle drifted here too, though thinner, like pollen rather than rain. Bioluminescent plankton should have shimmered along the rock ridges; instead they blinked out one by one, leaving patches of darkness that unnerved me more than any shadowspawn.
Veshra drifted to a halt at a fork in the canyon. "Light starvation," she murmured. "Plankton use trace mana, and the drizzle pulls that trace away." She raised the mirror shard, catching lamp-beams and spinning them into a tight cone. Plankton inside that cone flickered awake, bright for a heartbeat, then faded as she lowered the shard. "Proof of concept."
I nodded, but Echo-Hand cut in, "Mirror tricks will fail down-murk. Crystals sing a different chord, stronger against thin drizzle." They lifted one gloved hand, showing a faint cut on the pad, violet residue hissed there a moment, then dissolved in the water.
Rejah's scanner pinged low energy. "Then we keep moving. Show us the pocket."
Echo-Hand led us along a narrow slot where the canyon wall looked folded upon itself. I followed, wary. Each time I tapped the pearl for a stabilizing eddy, the ringing in my ears rose in pitch, then ebbed only when I released the flow. My lateral line blurred for a breath, outlining shadows that were not there, a disorienting haze that forced me to blink hard.
We squeezed between fins of basalt and emerged in a vaulted chamber. Blue quartz veins streaked every surface, radiating their own faint melody, barely audible yet felt in the chest like a distant flute. Crystals sprouted from floor and ceiling, some as thin as reedgrass, others thick as tide pillars. They vibrated when our lamps hit, scattering motes in tiny arcs.
Veshra's eyes shone behind her visor. "Quantifiable resonance," she breathed. She slid a chisel from her kit. "Echo-Hand, which nodes first?"
"Core clusters closest to heat fissures." The guide pointed past a steaming crevice. "But harvesting calls the worms."
Rejah frowned. "How territorial?"
"Enough that they taste mirrors before strangers."
I tightened my grip on the spear. "We work fast."
Veshra and Echo-Hand anchored a lattice of chisels around the brightest crystal bloom. Each strike released a hum deep enough to tickle my gills. I steadied a containment swirl underneath to keep shards from drifting. Rejah recorded harmonic shifts, her slate pulsing gentle gold.
When the third core cluster cracked free, the chamber walls answered with a low groan. Silt dust rose. Echo-Hand froze, mask turning toward a black seam in the far wall. "They wake," they whispered.
The seam widened. A segmented worm, spine plated in shadow-glazed scale, slid free with eerie silence. A smaller worm followed, coils rippling. Their eyeless faces bore rows of cilia that tasted water. They oriented on the crystal hum, then on us.
"Scatter pattern six," Rejah hissed.
I flared a water lens, thin as glass, using Veshra's lamp to lace the beam. Motes inside the lens erupted, spraying violet sparks into the worms' cilia. The larger worm recoiled, but the smaller surged forward, jaws like serrated coral snapping at Veshra.
Echo-Hand crossed its path in a blur, twin hook blades flashing. One blade caught the worm's gill fold, burst a pocket of oily fluid. It shrieked, felt more than heard, twisting to coil Echo-Hand. I thrust my spear through the loop, forcing it wide. The ringing in my head spiked so sharply I tasted copper. My lateral vision smeared, yet I pushed water harder, shaping a hammer wave that slammed the beast into quartz spires.
Rejah hacked twice at the plated segments, carving through joints. The worm convulsed then drifted limp. The larger worm tried to retreat, but a reflected beam from the crystal lattice blinded it. I lunged, caught the fissure behind its jaws, driving bone into core. The beast folded in on itself, motionless.
Victory tasted like stone dust.
Then the whistle in my skull rose so high it became silence. The world blurred for a breath. Rejah's hand closed on my elbow. "Easy," she said quietly. "You are bleeding from one ear ridge."
I touched the ridge, felt warmth drift into the water. "Overreach," I muttered, pulling a steady breath. The pearl flared once, then steadied, like a warning glare from a tired mentor.
Echo-Hand retrieved the final crystal cluster. "We linger too long. Rise, through the vent."
The vent was a jagged slit climbing toward faint light. Echo-Hand swam first, blades away, guiding by touch along the stone. Rejah tucked the crystal crate against her chest. I followed, mind splitting between shielding them and controlling the tremor in my arms. The ringing calmed to a dull throb as we ascended, but my lateral line still flickered, sensing shadows too slow or too fast.
Halfway up, Rejah's scanner went dark. She smacked it, nothing. Echo-Hand paused. "Vent shifts," they said. "Follow my handholds."
Trust an Exile or turn back into motes and worms? The choice was an illusion. "Lead," I said.
Hand over hand we climbed, the stone warm from geothermal veins. Echo-Hand's route bypassed lit city conduits, slipping through abandoned mining ducts and narrow surge pipes. Each bend felt wrong, like walking hallways of a house you had known in childhood but rearranged by strangers. Yet we emerged into a mid-level runoff gutter within sight of reef watchlights.
Veshra exhaled relief. "Crystals intact." She patted the crate. "Now to prove they can protect crops."
Echo-Hand watched the lights across the reef, mask unreadable. "We trade knowledge," they said softly. "Decide if your council values knowledge more than comfort."
Before I could answer, a faint shimmer drifted past my visor. Motes—but no, these motes moved upward, climbing the current as though gravity had reversed.
"Motes are rising?" I whispered, watching them thread into the dark above.
"No," Echo-Hand replied, voice cool behind the mask, "something below is breathing them in, and we are walking toward its mouth."