The waters around Blackreef Island were the color of clotting blood.
Lion stood at the bow, watching the fog-shrouded silhouette of jagged cliffs emerge. The waves here slapped the hull with a sick, wet sound—like some great beast swallowing. Since entering these waters, his Shadowheart had pulsed in eerie syncopation, as though answering a summons.
"Tide's turning." Calvin's voice came from behind. The old knight wore his antiquated drakescale armor, its central crest matching the one Frostscar had preserved in ice. "We make landfall before sunset or—"
"Or what?" Lion turned to find Calvin wrapping oil-soaked bandages around his iron hook.
"Or you'll learn why they call this the Boiling Trench." The knight ignited the bandages—flames burning ghostly white in the humid air. "Every Bloodmoon, the Corruption fissures erupt. Took twenty dragon-riders to seal the main vent three centuries back."
As the skiff closed in, the "reefs" resolved into horrors—thousands of crystallized corpses frozen in agonized poses along the shore. Dragonkin. Conclave adepts. Twisted things unidentifiable.
"Containment breach." Calvin pointed his flaming hook toward a prominent figure. "Third warden. Tried freeing the 'Vessel.'"
The corpse clutched a crystalized logbook. As Lion reached for it, his Shadowheart spasmed—the cover bore Selene's face in blood, split down the middle: one side benevolent, the other monstrous.
At the island's heart loomed a grotesque black tower, its surface veined with pulsating ridges. As they approached, those "veins" squirmed—the structure splitting open along a yoning fissure that dripped viscous fluid.
"Welcome home, traitor." The tower's voice was Selene's—layered with an elder woman's tones.
Calvin's eye twitched violently. He tore off his left vambrace, revealing festering skin now patterned with identical veins. "They activated my watcher spores. Lion—inside, trust nothing—"
The tower convulsed. The fissure yawned wide, sucking them in.
Lion fell for ten stomach-dropping seconds through mucilaginous channels before slamming onto a hemispherical chamber's membrane floor. Below his feet, gray-white flames churned. And at the center...
"Selene?"
Two of her.
Back-to-back against a crystal pillar—one in tattered Conclave robes (flesh-left arm, crystal-right), the other their missing companion (drakescale prosthetic glinting). Their hair was braided together, threaded with dancing gray flames.
"At last, the Shadow Vessel." The robed Selene lifted her head—left eye gold-red, right corpse-gray. "I am Aelin, Seventh Seat of the Conclave. Or... 'sister,' if you prefer."
Lion's shadow-tendrils wilted upon exposure. The air thrummed with magic-nullifying spores.
"Don't bother." Aelin's rune-carved teeth gleamed. "This tower lives. It feasts on—"
Her scream split the air as the other Selene slammed her prosthetic into the pillar. Cracks spiderwebbed across the chamber.
"Run..." Their Selene rasped, her right side fully crystallized. "Mother made us... filters... she—"
Aelin's hair-flames lashed out like vipers. Calvin intercepted with his burning hook—immolating his own leg in the process.
"Should've done this... twenty years ago..." The knight laughed through the pain, driving his hook into his chest scar. Dragonblood sprayed, forming ancient script in midair:
[BY WATCHER'S BLOOD, THE ETERNAL PACT BREAKS]
The tower came apart.
As both Selenes fell toward him, Lion saw the truth in flashes:
A laboratory three centuries past. Selene's mother cleaving an infant's soul—one half gifted with phoenix-fire, the other made Chaos-touched. And Calvin in the shadows, his lance through a Shadow Prince who tried to stop it...
"Vessels must be paired..." The twins spoke as one, their bodies merging against their will. "...filters require dual poles..."
The floor turned transparent. A hundred feet below, a colossal heart pulsed in the gray flames—the Corruption's true form. With each beat, it ejected memory-fragments:
The Shadow Royals willingly becoming shackles.
Dragonkin and Conclave rewriting history.
And the crucial lie—Selene's mother as Patient Zero of Corruption.
"Now you see." The merging Selene's voice overlapped. "The Chains were always the deception... Mother spent three centuries letting Corruption seep into every race..."
Calvin crawled through fire, pressing something into Lion's palm—another Heartchain fragment, twin to Shadowglow's.
"Stab it... through her heart..." Crystallization crept over his face. "Only Twin Vessels... can reforged the true seal..."
The Shadow Prince's voice came clearer than ever:
[WE WERE DECEIVED. THE CORRUPTION IS NOT THE ENEMY—IT WAS THE FIRST PRISONER.]
As the Selenes fully merged, the entire trench erupted.
In the apocalyptic flames, Lion made his choice—
He plunged both fragments into his own Shadowheart.
The sixth chain shattered.