AN: Laura, this is for you. You gave me the headcanon, so, enjoy. And for me, well, I asked if I could write an effective story without any dialogue whatsoever. Tell me what you thought.
For those of you so inclined (basically everyone, I guess) there is a deeper, more explicit version of this over on AO3, here archiveofourown org/works/4390574
Elsa heard it first after visiting the trolls—at Anna's insistence that they could help with her magic. They couldn't. The sound was soft and distant, carried far by an ethereal wind. It sounded like a voice, or a river, or a forest come alive. It was green—it felt green, it sounded green; the green of grass, of treetops and forest canopies. It was music—the song of earth; rivers and valleys and mountains and sky. It was haunting and familiar and altogether too beautiful for words. Elsa felt drawn to it so strongly that she only realised she was far off the path when she nearly tripped over a large root, cursing softly.
The song was gone.
There was a cave, in the border forest, and through it she could see the sky. Anna had shown it to her, so long ago. She looked up, the water falling in steady sheets from on high, into this secret place. Far, far above the sky was awake, twisting flashes of green and blue; flickers of red, and sudden glimpses of brightest yellow. The stars fell behind the spectacle, and the world seemed to drift away.
Deep in the water she heard it again. Coming up from the earth was a song that held a promise of life, and beauty. It was green, and quiet. It promised a soothing death, and a glorious rebirth. There would be no ashes on this wind, but great trees grown from the smallest seeds. A song of life, and a song of death. A song of the Earth itself. It was different than before, but still hauntingly beautiful and ethereal. There was no way to catch it but to drift free from herself.
She swam in water so black it mirrored the sky, stars mixing with cresting ripples and the voice of rushing water. Time passed, and the song ended. Elsa blinked, and the sun had risen above.
The third time she heard it, Elsa was in the depths of the castle. The song drew her down, deep, deep into the Earth. It echoed from the walls, and the dark stone turned to green life as the ethereal voice wove about the earth behind them. Her hand brushed the wall, moss clumping on her fingers. A dusting of ice cleaned them and spread over the wall. The moss grew back, cracking the ice in perfect silence, the song unabated. Elsa let out a quiet breath.
The song soothed her tangled nerves, taking her mind to a place of green, of tall trees and soft earths; of rushing waters and calming skies. It was no threat. The song had been touched, by something very strange, and had tried to respond in kind. She had no idea how she knew this from the wordless song, but it spoke to her as if it were a thought, not a sound. The song drew her to the deepest tunnels, beneath the fjord, and up, out into the forest.
But in the evening air the song was gone, its haunting melody a sense of great loss. Elsa sat, and wept, but could never say why.
She had wandered far, deeper into the forest than ever before. Far beyond the valley of the living rock. Beyond the trolls. Beyond the paths. Possibly beyond Arendelle itself. The air was still, and the earth soft underfoot. With barely a thought she dispelled her icy shoes, luxuriating in the feel of earth beneath her feet. It felt right. Something brushed gently against her foot. Deep green moss. Then the song began, quiet and longing; ethereal and haunting.
A song of death, and loss, of life, and rebirth. A song of cycles, of seasons. A song of the Earth itself. Carried on the wind as a whisper of a thought, it pulled her ever onward. Green the forest was, green too were the trees. Even the sky itself shaded to a green, not eerie but alive. The song was powerful, and she was close—closer than ever before. She could see the singer now.
Bare flesh, tinted slightly green. A spine gently curved, and hips so shapely they chased confusing thoughts of jealousy and arousal through her mind. Legs, thick and strong like the trunk of a tree. A body shaped like flowing water, sinuous curves and deep gullies. Shoulders solid and hard as rock, with arms as pliable as soft earth—or as strong as bedrock below. Hands and fingers that worked with the delicacy of a falling leaf. The figure turned, and Elsa's dress was gone, gently pulled away by a hidden greenness, yet she didn't feel exposed.
They were women, meeting as equals, only as themselves. The song continued, calming any disquiet Elsa might have had. The green figure approached, and closer Elsa could see the lines, the way the woman's flesh was made of new leaves and old branches. A hand reached out to touch her face, and Elsa had to fight to keep her magic in check. A caress softer than any feather ran down her cheek and swept across her neck, sending a shiver down her spine.
The hand continued, over her shoulder, and down, tracing the line of her breasts before stopping over her stomach. The green figure looked at her with sadness and concern, slowly moving closer. Elsa blinked, gently reaching out. Green flesh pressed gently into white, and the figure hugged Elsa more fiercely than even Anna had ever done. She didn't understand. They sank to their knees, and Elsa felt tears against her cheek—and they weren't hers.
Elsa gently lifted the mysterious woman's chin, looking into eyes of emerald. A great sadness lay within, but so did a stronger feeling of relief. A subtle greenness had spread beneath them, and suddenly Elsa understood. This woman, too, had magic. Magic of life. But the song spoke of death. Because all life had to end; but it was born again. The green magic was the ultimate expression of life, and for a moment Elsa wished it had been hers, so that she could never have hurt Anna; so that she could have had a sister for all those years—Been a sister for all those years.
The green figure placed a hand over Elsa's breast, touching a finger to her heart. Elsa watched in fascination as a tiny string of emerald smoke was drawn from inside of her. She felt a start as something seemed to be missing—or stolen. The green figure placed a finger to Elsa's lips, forestalling any protest or question. With a subtle gesture she dug the emerald smoke into the earth below, and above there were suddenly the boughs of a yew, green leaves hanging in tight fronds.
Then Elsa finally understood why the song was so haunting. To bring a new life to fruition, an old life had to be taken. Nature had to balanced. The woman smiled at her, then pressed their foreheads together. Emotion overcame Elsa, and when she looked up the singing grove was gone. The forest path had returned. The stream had bent back to its original course.
All that remained was a single yew.