"Since this is a sword of light enhanced with additional spells and magic-boosting abilities, maybe it can..." Lina thought to herself as she began to concentrate and gather her magical power.
As a genius magical girl, Lina's magical power was immensely strong. While it couldn't compare to her sister Luna Inverse, among mortal sorcerers, she was undoubtedly at the pinnacle.
There was only one spell left. If she wanted to help Aoko defeat Shabranigdo and save the world, this was the only path forward.
"Rezo!" Gourry shouted unwillingly, "Are you content to watch Shabranigdo destroy the world, Rezo?!"
Shabranigdo, who was locked in fierce combat with Aoko, paused for a moment, giving Aoko an opening to strike hard. A magical projectile from her hit its mark, leaving a large wound on Shabranigdo's body and enraging him further.
"Huh?" The somewhat fatigued Aoko noticed something odd. "Is it a lingering soul? Or is it...?"
As Aoko pondered while fighting, she suddenly sensed a familiar yet unfamiliar energy coming from Lina's direction. It compelled her to turn and look.
At the same time, the Ruby-Eyed Demon King Shabranigdo stopped his attacks on Aoko and shifted his focus to something far more significant.
The voice of the young sorceress with fiery orange-red hair echoed atop the ancient tower that had stood for millennia. The stormy sky above grew even more ominous, filled with lightning and thunder.
"Sword, please lend me your strength...
"Darkness beyond twilight, crimson beyond blood that flows, buried in the stream of time is where your power grows..."
"I make a plea to thee, I make a vow to thee! Let all the fools who stand in my way be annihilated by the power you grant me!"
The dazzling blade of the Sword of Light was now engulfed in infinite darkness. An incomparably immense power and will descend from the heavens, converging upon the sword.
Lina Inverse's body trembled, but her resolute will never waver. She gripped the sword hilt tightly with both hands, struggling to restrain the overwhelming magical energy.
"Devour the darkness and transform into a blade—Giga Slave!"
The moment Aoko realized the nature of Lina's spell, she immediately used her arcane spell to retreat as far as possible from the area of effect. She was also deeply shocked, for within this magical darkness, she felt a sensation akin to the one she had experienced when she first encountered the Root.
"Just a mere human..." Shabranigdo, struggling under the immense pressure of the darkness, roared in frustration. "Do you think you can defeat me with just a fragment of the power of the Lord of Nightmares?!"
The destructive range of Giga Slave continued to expand, but Shabranigdo seemed to have gradually adapted to the pressure. A crimson barrier emerged around him to resist the encroaching darkness.
"Shabranigdo, you truly deserve annihilation," a voice—Rezo's—came from nowhere, sounding distant and layered.
"Don't bother me, you damned nuisance!" Shabranigdo shouted in fury. He hadn't anticipated that Rezo's mortal soul, after reviving this fragment of his essence, could still exist within his body.
The flow of power in the crimson barrier faltered for a moment before the blackness of Giga Slave corroded and shattered it. The spell struck Shabranigdo's body directly.
The profound darkness exploded outward, completely consuming the fragment of the Ruby-Eyed Demon King. However, before Aoko could catch her breath and retreat further, tendrils of darkness extended from the spell and dragged her into it.
"Eh?!" (in English)
Aoko's last words in this world, surprisingly, were a phrase of incomprehensible profanity from another world—something Lina and the others couldn't understand. The irony was palpable.
Swallowed by the darkness, Aoko didn't die. She felt oddly comfortable, as though soaking in a warm bath.
No sound could be heard, no objects could be seen. Even time and space themselves seemed to lose their meaning here.
This wasn't the first time Aoko had encountered such a situation. Memories of the last time she had been in a similar place suddenly resurfaced from the depths of her mind. She realized where she was.
"The Root… or rather, the Swirl of the Root?" Aoko mused. "But this isn't the Root I once reached. This must be the origin of everything in this universe."
"Who would have thought that little girl Lina possessed magic capable of directly summoning the Swirl of the Root? If the folks from the Clock Tower heard about this, they'd go mad with jealousy..."
As Aoko let her thoughts wander, she drifted aimlessly through the alien Swirl of the Root.
She had obtained the Fifth Magic from the Root of her own universe. What could she gain from the Root of this other world? Could it be this world's equivalent of the True Magic?
After an indeterminate amount of time, Aoko sensed an unfamiliar will within the void. At first, it seemed curious about her, scanning her from head to toe. But soon, it lost interest and left her alone.
"How am I supposed to leave this Swirl of the Root? Am I going to turn into Kars or something?" Aoko pondered.
Perhaps the will within the Root grew bored, or perhaps she had drifted long enough. Suddenly, she found herself back in the flow of time and space. Light and shadow, heat and cold, the breeze brushing against her skin—all of it returned.
And then, so did the voices of her companions.
Floating in midair, Aoko blinked and realized she was back in the real world. Before her were her teammates—Lina, Gourry, Zelgadiss, and Golf—rushing toward her.
"I'm sorry, Miss Aoko!" Lina cried, rushing up and hugging Aoko tightly. Aoko could feel the girl trembling slightly, seemingly tormented by the guilt of accidentally hurting her. "I thought you were gone..."
"Things are complicated, but it's not your fault," Aoko said, patting Lina on the back. "Are you all okay? Let's talk more after we land."
The five members of the Rezo Subjugation Party returned to the ground. Considering the complete devastation of the surroundings (as Rezo's tower had been obliterated), they decided to retreat to a nearby town.
At a local tavern, Lina treated everyone to a feast, ordering a table full of food. As they ate, they discussed the details of the battle.
Some topics were sensitive, so Aoko had to use soundproofing magic to ensure their conversation couldn't be overheard.