(Kaelen narrates unless noted)
Water hammered the heart chamber like a drumline gone mad. Cables as thick as reef roots lashed from the sphere overhead, rune‑tips spitting sparks each time they struck stone. I parried one swipe, steel rang, shoulders jarred, and slammed against a pillar of cracked glass‑bloom. The pillar chimed; pain thrummed down every rib.
Move, I told muscles that wanted to cramp. Move or drown on your fins.
Lis's anchor cannon fired, tether bolt yanking a flailing cable aside so Ashekan's blade could cut it clean. No triumph, three fresh tendrils dropped to replace it. The heart was fully awake, and the room itself had become our enemy.
A bass vibration rolled through the floor: faster than a swimmer's pulse, slower than drill chatter, steady as fate. Each beat pulled drifting motes into seams along the walls, feeding them to runes that glowed molten amber. The water tasted of copper slag. The pearl in my chest begged for calm; calm was impossible.
I coaxed a ribbon of current around my cracked wrist crystal. Violet sparks bled through my glove as migraine heat climbed my spine.
"Veshra," I called, voice shaking more than blade.
She knelt by a fallen strut, helm lamps flickering against her slate. "Runes at meltdown temp. Cooling spiral or we boil."
"Working," I muttered.
A cable swept toward her. Ashekan vaulted, blade intercepting the strike in a spray of amber shards. The tendril recoiled, scoring a smoking trench in the glass‑bloom floor.
Lis
Anchor spool screamed, gloves smoking where friction bit. First deep patrol and the ceiling sprouted nightmares. A skitter drone crawled a conduit, bleeding motes like puppet string. I swung the cannon and fired. The spike punched its shell, marking but not killing.
"Second contact, overhead," I barked.
Rejah's calm reply flowed through comms: "Drone mass three stone, organ‑count one." Irregular organ meant unpredictable, lovely.
Kaelen
The pearl thumped once, heavy as a warning bell. I spread both arms, guiding cooler water from fissure vents into a broad spiral. Motes fluttered, cables slowed. Chest grafts in the sentinel above us glowed sunset orange, halfway between spent red and hungry yellow.
Echo‑Hand, helmet off, salt scars bright, slipped beneath the wavering tendril and cut a cable linking graft to spine. "Heartlines severed," he announced, voice low but certain.
Salt‑sweet tang filled my mouth; pressure ballooned behind my lateral line. Vision narrowed, held. I spun a tighter lens to keep Veshra covered, though every turn sent migraine sparks skittering.
Rejah's numbers sliced through the chaos. "Mote density down thirty, core output dropping."
Veshra wedged broken planter lids into the wall, turning them into mirror baffles that kicked sonar back at the sentinel. Its pings stuttered. The skitter drone slewed sideways, Lis's second spike shattered its graft. Motes gushed, violet and angry.
The sentinel rasped five clipped clicks, first words we'd heard from living metal. No one understood, everyone felt the threat.
Fog thinned, revealing a spiral hatch rimmed in turquoise. Tracks vanished into gloom, rails wrapped in mineral vines. A rusted ore cart lay like a carcass.
"Report or pursue?" I asked, heart hammering.
Lis looked to Ashekan. The floor's tremor sped up, heartbeat of something larger waking.
"We move," Ashekan decided. "Hearts grow faster than wounds."
We clipped to the rails and descended. Cold bit exposed palms; helm lamps pushed back dark. Turquoise veins pulsed in the rock. I brushed one, it buzzed like distant thunder. Echo‑Hand whispered Exile scripture: "Stone cords coil, metal pollen sleeps, silver breath obeys the buried king." Veshra recorded each word.
At the first landing, a fossilised drill head slept half‑buried. Shadow‑plant vines turned to crystal wrapped its frame. My visor reflected there: lines of fatigue I hadn't earned a cycle ago.
Pearl strain shrank vision to a tunnel. I counted teal veins across my wrist, five bright, three dim. We pressed on.
The second platform smelled of copper. Rail lights flickered violet, matching my pulse. Above, rumble of cables slackened; below, something larger inhaled.
The rail ended at a cavern bigger than the hatchery plaza. Dim amber runes ringed the walls, restless but contained. Cracked glass‑bloom crystal carpeted the floor, magnifying every whisper into a crawling undertone that tickled gills. The sentinel's corpse had fused to stone, organs still glowing orange, cables draining them deeper.
Five cautious strokes forward. The ceiling unfurled. A sphere of metal muscle glided free, cables pulsing like veins. Runes ignited, flooding the cavern with honey‑dark light.
The room inhaled, and somewhere far above, the reef seemed to flinch.
Pressure folded inward, wrenching mind from body. Machine constellations bloomed in darkness: rings nested in trenches on worlds under alien suns. A thought not my own asked, Why does the water resist? I clutched the memory of demi‑god lessons, screamed silent refusal, and the vision tore away.
Ashekan's arm yanked me behind a cracked column. "Live now, dream later," he snapped.
Rejah called, "Core temp down ten, maintain spiral!"
I drew colder current, weaving layers like tangleweed baskets. Frost crawled over cables; amber dulled. The heart convulsed once, then sagged. Runes dimmed to tired embers.
Water fogged my visor. Even quiet weighed heavy.
Lis slumped beside her cannon. "No one warned me architecture could hate."
Veshra tapped her slate; relief and worry shared her gaze. "Pulse neutral. Second wake, and we're lanternless."
Echo‑Hand laid a palm near the sleeping shell. "Sleep is not death."
Amber runes pulsed once, faint but sure.
We stood in the hush. Our reef would feel this heartbeat soon, and we had no idea whether it would wake as guardian or butcher.