The twin moons of Elyndria cast their silver-blue light across the Whispering Plains, illuminating the frost-tipped grass that swayed in the midnight breeze. Lyra Moonshadow crouched at the edge of the ancient standing stones, her fingers tracing the ethereal runes that pulsed with a light that hadn't been seen in the realm for over three centuries. The Etherfrost—that mysterious convergence of elemental energies that once allowed communication between the living and ancestral spirits—was stirring again.

Behind her, Thorne Blackthorn adjusted the twin blades strapped across his back, his eyes constantly scanning the perimeter. "You're certain this is the place from your vision?" he asked, voice low and graveled from years of command in the Stoneheart Legion.

"I'm certain," Lyra replied, not looking up from the runes. As the last living Resonance Mage, she alone could interpret the ancient language of the Etherfrost. "These markings speak of the Severing—the cataclysm that separated the spirit realm from ours. But there's something more..." Her voice trailed off as her fingers found a pattern she didn't recognize. The rune beneath her touch flared with sudden intensity, sending a pulse of energy up her arm that manifested as frost-like patterns across her skin.

Thorne was at her side instantly. "What happened? Are you harmed?"

Lyra stared at the crystalline patterns spreading across her forearm, not with fear but with wonder. "No... I think it's responding to me. The old texts mentioned this—the Frostmark. Only those carrying the bloodline of the Ancient Wardens could bear it." She looked up at her companion, amber eyes wide with realization. "My mother always said our lineage was ordinary, that we came from simple herbalists from the Verdant Glades."

"Apparently," Thorne said with the hint of a smile, "she didn't tell you everything."

A sudden chill swept through the standing stones, carrying with it a whisper that seemed to come from everywhere and nowhere at once. "Find the Keystone. The veil thins. They are coming through."

Lyra and Thorne exchanged glances as the whispering faded. Far to the north, beyond the Frostpeak Mountains that served as the realm's natural border, a column of ethereal light pierced the night sky. The ground trembled beneath their feet.

"Whatever's happening," Thorne said, drawing one of his blades with practiced ease, "it's happening now."

Lyra rose to her feet, the Frostmark now extending up to her shoulder and pulsing in rhythm with her heartbeat. With her free hand, she withdrew the ancient map they'd discovered in the ruins of Thornwood Abbey. "The Keystone," she murmured, studying the faded markings. "According to this, it lies within the heart of the Spiremist Catacombs."

"The catacombs?" Thorne's expression darkened. "Those tunnels run beneath the Blighted Lands. No one has ventured there since the Shadow Plague a century ago."

"And that," came a new voice from the shadows beyond the standing stones, "is precisely why it's the perfect hiding place for something of such immense power."

Both companions turned, weapons ready, as a figure emerged from the darkness. Tall and lithe, with skin that shimmered like polished obsidian and eyes that gleamed with an inner light that mirrored the stars above, the newcomer wore robes that seemed to be woven from the night sky itself.

"Erevan Nightsong," Lyra breathed, recognizing the last of the Starborn Elves, a race long thought extinct after the Mage Wars. "The histories said you perished defending the Western Gate."

The elf's ageless face showed a flicker of amusement. "History, dear Resonance Mage, is written by those who rarely witness its true unfolding." His expression grew serious as he approached the stone circle. "The barriers between realms are failing. The Void Wraiths sense the weakness and gather their forces. If the Keystone is not returned to the Etherwell before the convergence of the three moons in seven days' time, the Severing will be undone—and this time, there will be no Ancient Wardens to save your realm."

Thorne's grip tightened on his weapon. "And why should we trust you? The Starborn were allies of convenience at best, manipulators at worst."

Erevan's gaze fell to the Frostmark on Lyra's arm. "Because, Stoneheart warrior, I was there when her ancestor, Aria Moonshadow, used her final breath to seal the Etherwell and save your kind from annihilation. I made a vow to protect her lineage until the time came." He extended his hand, palm up, revealing a small crystal that emitted the same blue-silver light as Lyra's mark. "And that time, it appears, is now."

As the crystal touched Lyra's marked skin, ancient memories not her own flooded her consciousness—visions of a devastating war, of shadowy entities consuming entire cities, of a desperate ritual performed by seven mages as the world crumbled around them. And at the center of it all, a stone of impossible geometry that bent light around it in ways that defied natural law.

"The Keystone," she whispered as the visions receded. "I can see it. I know where it is."

In the distance, the column of light intensified, and with it came the unmistakable sound of something ancient and terrible awakening from its long slumber...