In the bustling metropolis of some modern Earth, oblivious to existential threats most days, Saitama flipped through a sales flyer with an expression of intense concentration he rarely showed monsters. "Hmm, the vegetable sale ends today..."
Suddenly, the air around them ripped open. It wasn't a physical tear, but a dimensional one, a purplish-black hole that opened soundlessly, swallowing a nearby takoyaki stand before expanding to engulf the bald hero. Saitama blinked, the flyer still in his hand. "Ah. A portal? I hope it doesn't make me late for the sales." A strange robotic voice echoed directly into his mind, ignoring his apathy. [Alert! Individual classified as 'Existential-Class Anomaly Detected'. Meets requirements. Initiating dimensional extraction process.] Saitama yawned as darkness enveloped him.
In the Jura Tempest Kingdom, Rimuru Tempest, in his human form, was reviewing reports with Shuna and Shion. The peace had lasted for a while, allowing him to focus on administration. Suddenly, he felt a cosmic disturbance, something not even Ciel could immediately identify, an echo resonating through his federation's web of souls and mana. The space around his desk distorted, the air growing thick with energy that was neither mana nor spirit energy. A translucent screen appeared before him. [Beings with 'Domain Lord' potential detected. Meets requirements. Selected for participation in 'The Nexus'. Initiating transport.] Rimuru frowned. "Ciel, analysis!" [Analysis impossible with current data. Origin unknown. Threat level: Incomprehensible.] Before he could react, the distortion sucked him in, pulling him and part of his desk into the unknown. Shuna and Shion shouted his name, but it was too late.
In a dimension where magic was the norm, but physics was a suggestion, Cid Kagenou, alias Shadow, dramatically rehearsed a monologue by moonlight in a forest far from Midgar Academy. "Yes... I am he who dances among the shadows... he who pulls the strings of fate unseen... the Eminence..." A sudden shock in the very fabric of reality interrupted him. The night sky was tinged with a strange aurora, and a sensation of being watched by something vast washed over him. Cid (Thought): This is it! The next phase! A larger force, manipulating dimensions! Exactly the sort of scenario where the Eminence must make an unexpected appearance! This must be the work of... a secret faction within the Cult? Or perhaps an even more shadowy organization? Intriguing! A strange interface, like a poorly made game screen, flickered in his vision. [Unit 'Latent Eminence' detected. Meets requirements. Beginning integration into the 'Nexus Theater'. Let the performance begin! Cid smiled beneath his mask. "The performance... it was always in the cards," he murmured, allowing himself to be drawn into the distorting light.
Meanwhile, in other corners of existence: Sung Jinwoo, overseeing the training of his shadows in his desolate Eternal Realm, felt a chill that did not come from death. An alien, domineering presence invaded his conceptual domain. The air around him solidified into unfamiliar runes. [Shadow Monarch ranked. Meets requirements. Joining the 'Prime Arena'.] Jinwoo clenched his fist, his shadow armor materializing. "An... invasion," he snarled, but he was unable to withstand the force that tore him from his throne.
In the vibrant world of sorcerers, Gojo Satoru was about to play a prank on Nanami when he sensed something his Six Eyes had never perceived before: a "wall" or "boundary" crumbling on a cosmic scale. It was fascinating. "Oh! What the hell is this? This is new," he exclaimed with a smile. ['Immeasurable Singularity' entity detected. Meets requirements. Adding to 'Participant List'. Enjoy the show.] A perfect geometric portal, surpassing even the complexity of his own spatial techniques, opened at their feet. Gojo took a casual step. "Well, a little excitement is always good."
And in the sleepy village of Easton, Mash Burnedead had just finished his giant log bench press routine and was reaching for his fill of profiteroles when the sky split. It wasn't magic; it was something alien, a dull, echoing sound that seemed to come from everywhere. A disembodied voice, simple and direct, boomed. ['Pure Force Anomaly' unit detected. Meets requirements. Teleporting to Play Area. No complaints!] Mash tilted his head. "Play Area? Are there profiteroles there?" Before anyone could answer his question, a bright light enveloped him.
Six figures abruptly materialized in a vast, empty dimension. The floor was a metallic gray slab that stretched to an indefinite horizon, beneath a perpetually twilit sky dotted with stars that belonged to no known constellation. In the center, floating in the air, was a massive geometric structure, emitting a faint, constant light, which appeared to be the source of the robotic voice.
[Welcome, Participants! You have been gathered in The Nexus. You are the identified Singularities from your respective realities. You will be divided into teams for a series of confrontations. The rules are simple: Defeat your opponents. The victorious team may proceed. Those who do not meet the requirements will be... returned. The teams are as follows.]
Two elevated platforms appeared on opposite sides of the arena. On one, Cid, Rimuru, and Saitama materialized. On the other, Jinwoo, Gojo, and Mash.
[Alpha Team: Participant 1-Alpha (Cid Kagenou). Participant 2-Alpha (Rimuru Tempest). Participant 3-Alpha (Saitama).]
[Beta Team: Participant 1-Beta (Sung Jinwoo). Participant 2-Beta (Satoru Gojo). Participant 3-Beta (Mash Burnedead).]
An awkward silence fell. Cid adjusted his gloves, observing the others. Cid (Thought): Alpha Team, huh. And Beta Team... just as I predicted. A simple organizational structure to mask the complexity. My teammates... the slime looks dangerous, but his aura is a bit... affable. And the bald guy... I don't sense anything from him. A masterful concealment technique! Or he's a low-level "extra" so low he goes unnoticed. Probably the latter. Interesting... I'll have to "integrate" them into my narrative.
Rimuru, in his human form, looked at his teammates. Saitama simply stared off into the distance with a bored expression. Cid was posing dramatically. Rimuru (Thought): Ciel, analysis on my teammates? [Ciel: Analysis complete. Saitama: Energy level undetectable by conventional means. Strength and stamina level: Infinite (confirmed by simulations based on dimensional data scanned during transport). Danger assessment: Maximum. Cid Kagenou: Mana level: Unlimited. Mana control: Perfect. Abilities: Numerous and constantly evolving based on... "self-proclaimed fantasies." Danger assessment: Extreme, unpredictable.] Rimuru broke out in a cold sweat. "Both are... impossible," he muttered to himself.
On Team Beta, Jinwoo was sizing up Gojo and Mash. Gojo was smirking, Mash was looking around for something edible. Jinwoo (Thought): Gojo Satoru... I felt his power in the breach. Dangerous. His energy... not mana or spiritual energy. Different. And the other one... Mash. I don't feel power, just a ridiculously dense mass of muscle. Some kind of physical anomaly? This System... has brought us together with freaks from other realities.
Gojo laughed. "My, my. Look who we got. The shady guy and the... muscle? This should be fun." He patted Mash on the shoulder, who stumbled slightly from the force, something that surprised Gojo for a moment. "Wow, you're tougher than you look, Muscle. Got any tricks?"
Mash blinked. "Trick? Just punches."
[The System: The first round will begin shortly. First match: Cid Kagenou vs. Sung Jinwoo.]
A section of the main arena lit up, forming a battle arena. Cid and Jinwoo felt a force pulling them toward it.
Cid (Thought): Here we go! Act one. The showdown of the "shadows." Just as I planned. The "Shadow Monarch" must be a high-ranking lieutenant in this "rival organization." Time to show him the difference between a mere shadow and the true Eminence.
Sung Jinwoo (Thought): The one with the cape and the weird lines? His power is real, but his attitude... strange. "Shadow Monarch" vs... Eminence? This is going to be complicated.
Both stepped onto the stage of the duel, the tension palpable in the air. The System was preparing to watch.