The chalk dust motes danced in the afternoon sunbeam cutting across the classroom. Ryohei Seiji watched them, his mind a million miles away from the droning lecture on the Heian period. In his head, he was running alongside a crimson streak of justice, hearing the roar of an engine and the triumphant cry of a hero.
"...and thus, the shift in political structure…" the history teacher's voice was a distant hum.
Seiji's fingers, calloused and strong from years of relentless training, traced the kanji for 'justice' on the cover of his notebook. Beneath it, drawn in meticulous detail, was the helmet of Kamen Rider Kuuga. He knew them all. Not just their names, but their hearts. The unwavering resolve of Godai Yusuke, the burdened hope of Tendou Souji, the burning passion of Kazuraba Kouta. Their chants, their poses, their power—it was his scripture. While his classmates dreamed of university and part-time jobs, Seiji trained his body and drowned himself in knowledge, fueled by a singular, burning hope: to become a grand hero, just like them.
"You're crazy, Seiji," his mother would sigh, watching him perform knuckle push-ups on the gravel driveway. "Heroes like that don't exist in the real world."
His friends would laugh, clapping him on the back. "Give it up, man! Come watch the game with us!"
But their words were like water on a duck's back. He saw their world as grey, his own painted in the vibrant, heroic colors of the 20 Heisei Riders.
The bell rang, a shrill sound that shattered his daydream. He began packing his bag, his movements efficient and practiced.
"Hey, Seiji," a voice called. It was the class leader, Charlotte Rin, her silver hair tied in a neat ponytail and her expression one of mild, perpetual concern. "You were zoning out again. Are you even prepared for the exams?"
Next to her was Takuma Ishimori, his bulk seeming to strain against his uniform. "Leave him be, Rin. He's probably planning how to shoot a Rider Kick in the gym." He chuckled, but it wasn't entirely malicious.
Mizuki Hinata, gentle and soft-spoken, offered a small smile. "I think it's nice to have a dream."
Megumi Mei, sharp and observant, just adjusted her glasses, her gaze analytical. "The statistical probability of developing superhuman abilities through self-training, however, is functionally zero."
Seiji just smiled, a quiet, knowing thing. "A hero's path is never understood by the masses."
Takuma rolled his eyes. "See? Crazy."
It happened as Seiji reached for his pencil case. The world didn't shatter or explode; it blurred. The classroom window, showing the familiar Tokyo skyline, warped and swam like a mirage. A nauseating vertigo gripped them all.
"What's happening?" Rin cried out, clutching her desk.
The air itself seemed to thicken, humming with an unseen energy. The fluorescent lights flickered and died, replaced by a kaleidoscope of swirling, impossible colors. Seiji's heart hammered not with fear, but with a sudden, electrifying anticipation. This is it, he thought, his knuckles turning white as he gripped the desk. A transition! Just like when they were pulled into the Game World!
The five of them—Seiji, Rin, Takuma, Mizuki, and Megumi—were the epicenter of the distortion. With a final, soundless pop, the classroom vanished.
Cool, damp stone met Seiji's knees. The air was different—thick with the scent of torch smoke, old stone, and something vaguely floral. He blinked, his eyes adjusting to the dim light of a vast, cavernous throne room. Banners depicting a roaring lion hung from towering pillars. At the far end, on a throne of white marble and gold, sat a man in regal robes, a crown of intertwined antlers upon his brow. His eyes, cold and assessing, scanned the five disoriented teenagers.
Guards in gleaming plate armor flanked them, their hands resting on the pommels of massive swords.
"Wh-where are we?" Mizuki whispered, her voice trembling.
"Silence," a guard boomed.
The king, Arthen, raised a hand. His voice echoed through the hall, practiced and grand. "Children of the other world. Do not be afraid. You have been summoned by the great ritual, called upon in our world's most dire hour." He leaned forward, his gaze intense. "The forces of the Demon King march upon our kingdoms. Darkness threatens to consume all of Landeran. You… you five are the prophesied heroes, awakened to save us."
A thrill shot through Seiji. Prophesied heroes. His years of training, his obsession—it wasn't for nothing. It was preparation. This was his call to adventure.
A wizened old man in deep blue robes, a staff topped with a glowing crystal in his hand, stepped forward. The court magician, Owyn.
"The awakening ritual will reveal your latent potential, your sacred gifts," Owyn intoned. "Step forward, one by one."
Takuma, ever impulsive, went first. As Owyn's staff hovered over him, a raw, orange aura erupted around Takuma's body. His muscles swelled, rippling with visible power. He laughed, a loud, booming sound, and effortlessly lifted a nearby stone bench meant for two guards. "Incredible strength! Yes!"
Next was Mizuki. A soft, white light enveloped her. She gasped, and a small, shimmering dove of pure light manifested in her hands, cooing softly before dissolving. "The Holy Force," Owyn declared. "The power to heal and purify."
Megumi was third. Arcane symbols, violet and complex, spiraled around her arms. A small flame ignited in her palm, then transformed into a swirling mote of water. Her analytical eyes widened with genuine wonder. "Fascinating. Direct manipulation of thaumaturgical principles."
Then, it was Rin's turn. The moment the staff passed over her, a brilliant, golden pillar of light shot towards the ceiling. When it faded, she was holding a sword. It was long and slender, its blade seeming to be made of solidified light, the crossguard shaped like unfurling wings. The very air hummed in its presence.
"The Holy Sword!" King Arthen rose from his throne, his voice filled with awe and triumph. "The mark of the Hero! The prophecy is fulfilled!"
All eyes then fell on Seiji. His heart was a drum solo in his chest. This was it. His moment. Would it be the form-changing power of Kuuga? The evolving might of Agito? The limitless imagination of Build? He stepped forward, his posture perfect, his mind clear and ready.
Owyn moved the staff over him. The crystal glowed… and sputtered. A faint, pathetic flicker of light appeared around Seiji, then died instantly.
A confused murmur ran through the court.
"Again," the King commanded, his brow furrowed.
Owyn tried again, chanting with more force. The staff glowed brighter, but when it passed over Seiji, nothing happened. No aura, no light, no weapon. Just a normal, slightly-too-well-built high school boy in a gakuran.
Silence. A heavy, oppressive silence.
Seiji's mind raced. No. This can't be. There must be a chant. A pose! He remembered the words of Emu Hojo. "A doctor's determination!" he shouted, striking a confident pose. Nothing. He recalled Eiji Hino's desire. "I want to help everyone!" Still, nothing. The cold stone floor seemed to leech the heat from his body.
King Arthen's face, once filled with hope, twisted into a mask of contempt and disgust. "Nothing," he declared, the word echoing like a death knell. "A dud. An empty vessel. You possess no sacred power." He waved a dismissive hand. "You are a waste of the ritual's energy. You are no hero. Guards! Seize him and cast him out from the royal capital. He is unworthy to stand in the presence of the true heroes."
The words hit Seiji harder than any physical blow. No sacred power. A waste. Unworthy.
"Wait!" Rin cried out, holding the Holy Sword. "Your Majesty, he's our classmate!"
"The prophecy speaks of five heroes, does it not?" Megumi reasoned, though her voice lacked its usual certainty.
"The king has spoken," a guard grunted, his grip like iron on Seiji's arm.
As he was dragged away, Seiji locked eyes with his classmates. Takuma looked away, almost embarrassed. Mizuki had tears in her eyes. Megumi looked puzzled. Rin's face was a conflict of duty and friendship. In that moment, he saw not his comrades, but the chosen ones, and he was the fool being cast into the darkness.
The massive gates of the castle city slammed shut behind him with a final, thunderous boom that sealed his fate. The sun was setting, painting the sky in hues of blood and orange. He stood on the dirt road, alone, the grand spires of the castle a mocking silhouette against the dying light.
Despair, cold and absolute, washed over him. All his training, all his belief, all his dreams—shattered. He was just a crazy kid after all. His parents were right. His friends were right. There were no Kamen Riders. There was no grand hero named Ryohei Seiji.
For three days, he wandered. He slept in ditches, scavenged for rotten fruit in market trash heaps, and drank from muddy streams. He learned more in those three days than in all his time in the throne room. He saw the gaunt faces of the peasants, heard the bitter whispers. Taxes were crushing. The king's knights were cruel. The "Heroes" were a distant, gilded hope, while the reality was hunger and fear.
"Maybe the Demon King ain't so bad," a drunken farmer slurred at a rundown tavern where Seiji was trying to stay warm. "Maybe he'll burn that bloody castle to the ground and we can start over."
The words festered in Seiji's soul. A tyrant king. A suffering people. Heroes who were oblivious, chosen not by merit, but by a fluke of magic. This wasn't a world that needed saving; it was a world that needed changing. And the king had declared him the enemy the moment he cast him out.
On the evening of the third day, huddled in a damp alley, hunger gnawing at his insides, he heard it.
Bzzt.
A sound, clean and digital, utterly alien in this medieval world.
In front of his eyes, a semi-transparent blue screen materialized, hovering in the air. At the top, in bold, blocky letters, was a line of text:
VANGUARD AWAKENING: YES / NO
Beneath it was what looked like a personnel file.
NAME: Ryohei Seiji
AGE: 17
GENDER: Male
BLOOD TYPE: O
DATE OF BIRTH: ...
ABILITIES:
- Kamen Rider Kuuga (Locked)
- Kamen Rider Agito (Locked)
- Kamen Rider Ryuki (Locked)
- Kamen Rider Faiz (Locked)
- Kamen Rider Blade (Locked)
...
- Kamen Rider Build (Locked)
- Kamen Rider Zi-O (Locked)
His breath hitched. His heart, which had been a numb, cold stone, began to beat a frantic, wild rhythm. This wasn't the kingdom's magic. This was something else. Something… familiar. This was a system. A driver interface.
Tears, hot and unbidden, welled in his eyes. This was his. Not a granted power, not a sacred gift. An awakening. With a trembling, but determined hand, he reached out and selected YES.
A mechanical, monotone voice spoke directly into his mind.
[Link successful. Equipment loaded. Enter the Armed Summon Command.]
A command prompt blinked at the bottom of the screen. There was only one word it could be. The word that had been his mantra, his prayer, his dream. He input the command, his fingers moving with surety.
[Armed Summon Command: HENSHIN]
The screen updated.
[Equip Now or Not?]
Seiji didn't need to think. He pushed himself to his feet, his body thrumming with a power that was not magical, but systemic. He concentrated his mind, drawing on every ounce of his training, every moment of despair, every spark of defiant hope. He stood tall, his feet planted firmly in the muck of the alley. He struck his pose—one arm thrust out, the other bent across his chest, a pose born of a thousand imaginations.
He took a deep breath, and into the quiet twilight, he shouted the word that would break his world and reshape it.
"HENSHIN!"
The mechanical voice responded instantly, devoid of emotion yet full of promise.
[Command enter complete! Loading Armor.]
The world erupted in a torrent of black and crimson light. Geometric lines of energy swarmed over his body, materializing into solid form. A jet-black, biomechanical armor encased him, sleek and powerful. On his chest, a crimson emblem resembling a stylized, roaring dragon glowed with inner fire. His helmet was a knight's visor, sharp and intimidating, the eyes glowing with a fierce red light. Power, raw and absolute, coursed through him—the power of 20 legends, now his to command.
From the nothingness, the mechanical voice announced his arrival to the world.
[VANGUARD! ROAR!]
Seiji—no, Vanguard—looked down at his armored fists, clenching them. He felt the strength of Kuuga, the potential of Agito, the contract of Ryuki, the speed of Faiz… all dormant, all locked, but all there. A arsenal of heroism, waiting to be unleashed.
He turned his glowing gaze towards the distant, illuminated castle, where a tyrant king and four oblivious heroes slept soundly.
A new thought, cold and clear, solidified in his mind. The words of the farmer echoed, merging with the philosophies of Riders who fought against corrupted systems.
If I can't be their hero… then being the hero's enemy isn't so bad.
He would not be a hero for the crown. He would be a warrior for the people. A nightmare for the fallen in power. He would protect the helpless and destroy the corrupt. He would walk his own path, clad in the armor of 20 heroes, a Vanguard of a new, darker justice.
"Let the game begin," he whispered, his voice filtered into a low, mechanical growl, as he took his first step into the shadows.