"You mean this, right?"
Shiratori Riku gave Tony no chance to react. In zero frames he produced his custom reactor.
It was no larger than two fingers, tiny yet radiating a stable and immense energy.
Tony's easy smile froze.
"What is that?"
"An improved arc reactor," Riku said mildly.
"I discovered a new element for the core and refined the design. Output is three times yours."
Tony's pupils tightened. He snapped his faceplate shut, and the HUD immediately spat out staggering numbers.
At the same time JARVIS spoke in his ear.
"Sir, he is correct. The device's output far exceeds our latest model, with no detectable side effects. It is effectively perfect green energy."
Tony took in the readings, then looked again with his own eyes.
He had to admit the person in front of him, or whoever built it, was a genius.
He lifted the faceplate, gaze grave, pride gone from his eyes.
"Who are you really?"
Riku chuckled.
"Me? Just an ordinary man among the masses."
The calm, slightly showy line made Tony's mouth twitch.
So this is what everyone feels when I drop a humblebrag.
He was quiet for a beat, then spoke.
"So your reason for flashing this at me was to peacock?"
"Fine, you succeeded. I..."
"No, no."
Riku shook his head and cut him off.
"Honestly, attracting you was an accident. I never planned to meet you."
"But once I sensed you coming, I changed my mind. I wanted to see you."
"Tony Stark, they call you the smartest man on this planet. That piqued my interest."
"So I want to test whether that claim holds up."
Tony's eyes lit with interest.
"Oh? Fun. First time someone has challenged my intellect."
"Your terms are abrupt and rude, but I accept."
Riku smiled.
"Refreshing. That is you, Tony."
"I will not take advantage. I know you are a busy man."
"Here is the deal. If you win first in the contest, I will give you this reactor."
"If you lose, I will not push you too hard... let us say you become my junior."
The proud Tony almost refused on instinct.
But seeing Riku's teasing look, he shut his mouth.
Fine. He cared too much about appearances.
Refusing would imply fear, and that he could not accept.
He was certain he would not lose anyway.
"All right, I accept. Kid, ready to lose? Try not to cry."
Riku chuckled, ignoring the jab.
"Since it is a battle of wits, let us start with your forte."
"You try to replicate my arc reactor, and I will try to break your AI."
"JARVIS, right? Great name. Soon to be mine."
Tony scowled.
"Fine. I would love to see you crack JARVIS."
"But there is no fabrication floor here, I..."
SNAP!
Before he finished, the world blinked.
They stood in a blank white expanse.
Riku swept his hand, and Tony's familiar benches, fabricators, even the idiot robotic arm sprang into being.
Tony stared in disbelief.
"How did you do that?"
Riku smiled like a man enjoying a show.
"A small trick, not worth mentioning. If you win, I will tell you everything."
"If you lose, I will also explain. You will be my junior by then, and a big brother should take care of his own."
Tony dragged himself back from shock and muttered, annoyed.
"Wow. Now I know how it feels to face a mouthy punk like you."
"You make me want to hit something."
Seeing Tony squirm made the mischief in Riku dance. He wiggled his shoulders and grinned.
"Oi, Tony, planning to borrow a victory before we start? That would make you unbeatable."
"But since you crave victory so much, I will toss in a small perk when I win. Deal?"
Tony inhaled, fighting the urge to swing, and said flatly, "Enough talk. Start."
Riku eased his smile and asked quietly.
"Tony, do you think you will win?"
"I will win."