Kuri stood atop a hill, the wind whipping through her hair as she overlooked the devastation in the valley below. The Source, a towering monstrosity of dark energy, tore through the land, its malevolence corrupting everything it touched. Trees withered, rivers turned black, and the air itself felt suffocating. The sight filled her with dread, but also with resolve.
Down in the valley, her allies fought fiercely.
Tanjiro's flames blazed across the battlefield, his Hinokami Kagura dances graceful yet ferocious. Each swing of his blade sent waves of fire crashing toward the Source, but it seemed to absorb the heat, growing stronger.
Nezuko, silent but determined, struck the ground with her bare feet, summoning tremors that cracked the earth beneath the Source. The demon staggered, but its strength remained unbroken.
Reiko's power surged as vines erupted from the ground, snaking toward the Source, attempting to ensnare it. The plants grew rapidly, blooming with vibrant, glowing flowers, but the demon burned them away with a single roar.
Zenitsu darted across the battlefield like lightning, his Thunder Breathing strikes flashing bright and fast. "Why won't this thing go down?!" he shouted, panic creeping into his voice despite his efforts to remain focused.
Reiko turned toward him, growling as she slammed her hand into the ground. The earth melted beneath the Source's feet, trapping it momentarily. "We'll find a way!" she called out, her voice fierce.
Kuri stood tall on the hill, watching her friends fight with everything they had. Their combined efforts were incredible, but it wasn't enough. The Source absorbed every attack like a bottomless void. Her grip tightened on Kiboken, the crystal blade at her side, and an idea began to take shape in her mind.
Kuri moved quickly, descending the hill toward the group. She raised her voice, calling to them. "Gather your powers! All of them! We can combine our strength into one attack!"
Tanjiro hesitated, glancing back at her. "Are you sure that'll work?"
"It has to," Kuri said firmly. "We don't have another choice."
With a nod, the group rallied. One by one, they channeled their powers toward her.
Tanjiro's flames danced, spiraling around her in a blazing vortex.
Nezuko stomped, sending tremors of energy rippling through the ground, adding an earthen stability to the swirling chaos.
Reiko's vines wove through the air, intertwining with the fire and earth, their luminous flowers glowing brighter as they joined the mix.
Zenitsu, trembling but determined, summoned a crackling surge of electricity, his Thunder Breathing adding a sharp intensity to the blend.
The energy gathered into a single point, a glowing cauldron of phosphorus light that hovered before Kuri. Her hands trembled as she mixed the elements together, infusing them with her own spiritual energy. The light grew brighter, pulsing with power.
"We have one shot at this," Kuri said, her voice steady despite the strain. She hefted the cauldron, now transformed into a glowing orb of pure energy, and ran toward the Source.
The Source roared as Kuri approached, its hollow eyes burning with rage. It lashed out, sending a wave of dark energy toward her. The ground cracked beneath her feet, but she didn't falter. She hurled the glowing orb toward the Source, the combined power of her allies slamming into the demon like a meteor.
The Source howled, its form beginning to fracture, but it wasn't enough. The cracks in its body started to seal, its energy returning stronger than before.
Kuri gritted her teeth, gripping Kiboken tightly. "This ends now," she whispered, surging forward.
She plunged the crystal blade deep into the Source's chest, the weapon glowing brightly as it absorbed the demon's energy. With her free hand, she threw the glowing potion from the cauldron directly at the wound. The Source screamed as the potion seeped into its core, its body beginning to break apart.
Kuri raised her voice, chanting with all her might:
"Ultimum potentiae statuimus,
Ultimum potentiae liberabit vos,
Ultimum potentiae et interficiam te laboravi rogans!"
The words echoed across the battlefield, the air trembling with their power. A massive explosion of light and energy erupted, shaking the valley to its core. The Source let out one final, terrible roar as its form began to disintegrate, its essence scattering into the wind.
"You kill me, and yet you summoned me here!" the Source snarled, its voice dripping with malice as it collapsed to one knee. "Die with me, witch!" With a final burst of energy, it lashed out, striking Kuri with its remaining strength and sending her flying backward.
"Kuri!" Tanjiro shouted, his voice breaking as he sprinted toward her.
She lay crumpled on the ground, blood pooling beneath her. Her breath was shallow, her eyes fluttering as she looked up at him. "Goodbye… flame heart…" she whispered, her voice barely audible, before falling still.
"No!" Tanjiro's cry echoed across the battlefield. He turned toward the Source, his grief and fury igniting within him. With a roar, he unleashed a final fireblast, the Hinokami Kagura dance reaching its apex as flames engulfed the Source, obliterating it completely.
The battlefield grew silent, the light of the flames fading into the cold night. Tanjiro knelt beside Kuri, tears streaming down his face. "Please… don't leave me…" he whispered, his voice trembling.
The stars above seemed to dim, as if mourning with him.