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The crushing pressure of the deep Abyss was a palpable, terrifying thing. Here, miles beneath the surface of Teyvat, light was a myth and the only sounds were the slow, rhythmic pulse of the Ley Lines and the faint clink of Tartaglia’s Hydro-infused chainmail.
Lumine, however, felt none of the crushing weight. She swam beside him, her body irrevocably altered. Her traveler’s cloak was replaced by finned, crystalline appendages, and her bright golden hair flowed around her like a protective halo. She was beautiful, silent, and terrifyingly adapted to this alien, deadly world.
Tartaglia watched her. They were in his makeshift Abyssal ‘palace’—a vast, hollow cavern stabilized by Geo-archaic structures and glowing faintly with the sickly purple light of corrupted energy. He loathed every moment he spent here, but it was the only place she could now survive.
“We found another anomaly on the perimeter,” Tartaglia’s voice echoed, resonant and deep, a sound she could feel in the water pressing against her skin, but could no longer answer. “It’s a remnant of the old kingdom. We should collapse it before it draws unnecessary attention.”
Lumine nodded, giving him a quick, sharp gesture. Yes, we must keep the borders safe.
He sighed, running a gauntleted hand over his newly scaled arm. His transformation was partial; he was not a fully adapted creature like her, but a terrifying hybrid—half human, half something else, scarred by years of deep-Abyssal exposure.
“It wasn't my attention I was worried about, Lumine,” he said, his expression grim. “I’m worried about the attention you draw. That light you carry is too pure for this place. It’s like a lure for everything we fought to escape.”
Lumine swam closer, resting her transformed hand on the chest plate of his armor. She looked into his eyes—the once vibrant blue now streaked with Abyss-black.
I am not afraid. I made my choice.
“A choice you never had to make!” Tartaglia snapped, his control breaking. He pushed off the wall, kicking hard through the abyssal gloom. “You came down here with the delusion that if you understood the Darkness, you could save your brother! And when the Void offered you the power to survive—the power to breathe the Abyss like air—in exchange for your voice, you took it without hesitation!”
He swam until he was facing a smooth, dark wall, plunging his hand into the surface and pulling out a perfectly polished, Hydro-crystallized shard of rock. He turned and threw it toward her.
“Look at this. This is your price, Lumine,” he commanded.
Lumine caught the shard. It was a perfect mirror, reflecting her terrifying, beautiful new face—her wide, expressive eyes and the absence of a mouth where her voice should have been. She held it steady.
I gave my voice to save the one person who could teach me how to fight the Abyss without being consumed by it. You.
Tartaglia swam towards her again, his movement fluid and deadly. He stopped inches from her face, the terrifying closeness a constant feature of their life down here.
“You still think there’s a happy ending, don’t you?” he hissed, his breath disturbing the water around them. “This isn't a surface world folk tale, Lumine. There is no kiss that breaks the curse. Your transformation is permanent. My exposure is permanent. Every single day, I feel the Abyss trying to re-write my mind, and I fight it so I can protect you—the only light in this crushing darkness.”
Suddenly, the cavern trembled. A high-pitched, resonant sound cut through the water—a sound that was pure Cryo energy.
Tartaglia immediately snapped into action. “Someone is attempting a deep-drill elemental intrusion! They are looking for the anomaly!”
Lumine pointed toward the ceiling of the cavern—a solid barrier miles thick. They are looking for me!
“No, they are looking for power,” Tartaglia growled, pulling his Hydro Vision to him. The water around his hands turned sharp, crystalline. “They will break through this vault. If they find you, they will dissect you. They will study the perfect fusion of the Traveler’s elemental power and Abyssal adaptation. You are the ultimate prize.”
“I am not going to let them,” he muttered, more to himself than to her. He raised his hands, preparing to unleash his most destructive skill—the one that would stabilize the cavern walls at the risk of causing more physical trauma to his already corrupted body.
Lumine darted forward, placing herself directly in front of him. She reached out, her hands glowing with pure, elemental Geo energy—the only element she still wielded fully from her Traveler days.
She pressed her Geo energy against his Hydro-infused chest, not as an attack, but as an act of solidification. The Abyss was chaos; Geo was order.
We stabilize together. We fight together. Show me your true form.
Tartaglia stared at her, the silent command clear in her eyes. He was Erik, forever tethered to the crushing deep, and she was Ariel, who gave up everything to meet him there. He was dangerous. She was deadly.
He let the Abyssal energy he had suppressed rise up. His form shifted: the Hydro was replaced by the chaotic black and red of the Foul Legacy Transformation, but this version was adapted to the water, scales glinting, horns growing sharp. He became a weapon of the deep.
Lumine was unfazed. She mirrored his intensity, channeling the Geo energy until she was covered in a sharp, protective layer of golden armor, her form terrifyingly beautiful in its silence.
“Fine,” Tartaglia said, a shark's grin splitting his face. “Let them come. I will show them why the Abyss is better left alone. But stay close. If you lose your anchor, you dissolve.”
The intrusion sound grew louder. Lumine gave one last, quick gesture that was both a promise and a threat. I will not be lost again.
They turned together, two perfect, terrifying entities bound by an impossible transformation and a desperate love, swimming into the dark channels to meet the invaders. They had traded light for darkness, voice for survival, and the warmth of the surface for the crushing, perfect truth of their eternal bond in the Abyss. Their horror was their home, and they would defend it together.