The frozen lake crackled underfoot as Su Changye dragged Ling onto the shore. The woman with ivory horns stood motionless, her starless eyes tracking their every move. The air thickened with a scent like burnt ozone, and the Heartstone in Su’s palm flickered weakly, its cracks deepening. “Who are you?” he demanded, shielding Ling with his body. The woman tilted her head, her horns casting jagged shadows across the ice. “I am Zhurong, Herald of the Eclipse. And you… are late.”
Before Su could respond, the ground trembled. The frozen lake shattered, shards of black ice erupting skyward like spears. Zhurong raised a hand, and the shards halted midair, trembling with pent-up energy. “The Eclipse demands balance,” she intoned. “Your light has delayed the inevitable. Now, you will rectify this.” She snapped her fingers, and the ice shards reconfigured into a bridge leading into the depths of the cavern. “Walk.”
Ling gripped Su’s arm. “Don’t trust her.”
Zhurong’s lips curved into a smile devoid of warmth. “Trust is irrelevant. Your brother’s blood sings to the Eclipse. He will obey… or watch you crumble.” As she spoke, Ling’s skin began to flake away like ash. She cried out, clutching her disintegrating fingertips.
Su’s left eye roared to life. Black energy surged toward Zhurong, but the Herald merely flicked her wrist. The attack dissolved, absorbed into her ivory horns. “Petty defiance,” she sighed. “The Demon Lord’s power is a child’s toy to me. Walk the path, Keybearer. Or let her die here.”
The bridge of ice glowed crimson, its surface etched with constellations Su recognized from the temple altar—the same map that had nearly claimed Ling’s life. “What’s at the end of this?” he growled.
“Truth,” Zhurong replied. “The truth of what you are… and what you must become.”
Ling’s knees buckled. Su caught her, his right hand glowing white to stabilize her disintegrating form. The effort strained the Heartstone further; a sliver broke off, disintegrating into dust. “Do it,” the demon within whispered, its voice tinged with unfamiliar urgency. “The Eclipse will devour her regardless. Save yourself.”
Su ignored it. He stepped onto the bridge, half-carrying Ling. The ice burned beneath his feet, searing through his boots. Zhurong followed, her footsteps silent.
The cavern walls shifted as they walked. Stone melted into fleshy membranes, pulsing with veins of molten gold. Ling gagged at the stench—rotting meat and scorched metal. “Where… are we?”
“The Threshold,” Zhurong answered. “Where realms bleed into one another. Where your brother’s bloodline will be… purified.”
The bridge ended at a circular chamber. Its walls were lined with mirrors, each reflecting a distorted version of Su: one clad in celestial armor, another wreathed in demonic fire, a third with Ling’s throat slit in his arms. “Illusions,” Su spat.
“Truths,” Zhurong corrected. She gestured to the largest mirror, where a figure in tattered imperial robes stood chained to a monolith. Su’s breath caught. The man’s face was his own, but aged centuries—his left eye a black sun, his right a dying star.
“The Heavenly Emperor,” the demon hissed, its voice laced with hatred. “Your ancestor… and your curse.”
Zhurong pressed a clawed finger to the mirror. The image shifted, revealing a battlefield strewn with corpses. A younger version of the Emperor drove a blade into a shadowy titan—the Demon Lord. “Millennia ago, your bloodline betrayed ours,” Zhurong said. “The Emperor sealed my master here, using the Eclipse as his prison. But blood calls to blood, Keybearer. Your sister’s life is the final key.”
Ling shuddered. “No…”
Su’s left eye blazed. “I won’t let you touch her.”
Zhurong laughed. “You already have.” She snapped her fingers. Ling convulsed, her body levitating toward the mirror. Cracks spread across her skin, glowing crimson. “Her blood is the Eclipse’s conduit. When it fills this chamber, the seal breaks. You can only choose how it happens—by her pain, or yours.”
The demon surged forward, seizing control of Su’s voice. “Let her die! Claim the Eclipse’s power and crush this wretch!”
Su fought the compulsion, his right hand tearing at his left arm. Blood dripped onto the Heartstone, its white light flaring. Zhurong watched, amused. “How poetic. The Emperor’s blood resisting his own descendant.”
Ling’s screams crescendoed. The chamber shook, stalactites plunging from the ceiling. Su slammed his fists together, merging light and dark into a storm of gray energy. The mirrors shattered, their shards embedding in Zhurong’s flesh. She staggered, her ivory horns cracking. “Fool! You’ve doomed both realms!”
Su ignored her. He leapt, catching Ling midair. Her blood seeped into his wounds, burning like acid. The chamber collapsed around them as he channeled the last of the Heartstone’s energy—not to attack, but to escape.
The world dissolved.
They awoke in a field of withered flowers under a sky torn between day and night. Ling lay beside Su, her wounds healed but her skin translucent, veins glowing crimson. The Heartstone was gone—only a scar remained.
“What… did you do?” she whispered.
Su stared at his hands. The left was scorched black, the right bleached bone-white. “I think… I merged our blood.”
The demon laughed, its voice clearer now—a mirror of Su’s own. “Clever boy. You’ve bound her life to yours. Now, when the Eclipse claims her… it claims you too.”
Ling touched her chest, where a faint light pulsed in rhythm with Su’s heartbeat. “How long do we have?”
Before he could answer, the ground split. A hand clad in rusted gauntlets clawed its way to the surface, followed by a figure in ancient armor—a man with Su’s face and Zhurong’s starless eyes.
“Not long,” the figure rasped. “But long enough to learn why you were born, brother.”