The lab was empty of Tony, but full of his chaos.
Half-assembled arc reactors littered every table.
A stack of DC comics reached the ceiling, practically holding up the roof.
Underneath it all was the classic Tony Stark aroma: raw ozone and fried wiring.
Leon stood in the center of it for a moment.
His super-hearing wasn’t something he left running continuously.
Like most things with him, it required a deliberate choice — a specific internal adjustment that filtered out the majority of ambient sound and let the rest resolve clearly.
Living with it permanently open would be approximately like trying to think inside a stadium.
He focused now, tilted his head, and expanded the radius.
Two floors down.
The sounds of something mechanical.
Of Tony talking, and then the specific metallic clink of robotic arms in motion.
The garage sub-level.
He found Tony standing in the center of a cleared section of floor on what appeared to be a jury-rigged experimental platform — cables running from his boots to a hand controller, three robotic arms positioned around the perimeter in what Leon recognized as a camera-and-safety configuration.
Tony’s eyes had dark circles under them but the expression in them was purely alive, the specific energy of a man who hasn’t slept in days because he’s been too interested in what he’s doing.
He was directing the arms with the casual authority of a conductor.
“DUM-E, I said record, not zoom in on my feet — yes, those, thank you.
U—” he pointed at a position on the floor, “—right there, hold.
And DUM-E, stay on standby for fire suppression.”
He turned back to the platform.
Rolled his shoulders.
Breathed slowly.
“Okay.” He shook out his hands.
“Ten percent thrust.
Controlled test.
Three.” He settled his weight.
“Two.” He adjusted his grip on the controller.
“One.”
He pressed the control.
The jets ignited.
The next second was a blur.
Tony launched off the ground at a velocity that was definitely not “ten percent.” He shot up six feet before his face even realized what was happening, slamming into the ceiling with a sickeningly clear crack.
Then he came back down.
He landed on his back.
The ceiling had not been kind.
DUM-E, reading the situation as per instructions, deployed the fire suppression system — and Tony, already in pain, received a full discharge of white suppressant foam across his chest and face.
Leon looked at this from the doorway.
“That must have hurt,” he said.
“Leon.” Tony’s voice came from somewhere under the foam, strained and very controlled.
“Come and help me.
I think something in my chest just complained very loudly.”
Leon crossed the floor, got a hand under Tony’s arm, and lifted him into a chair.
He made a quick assessment — nothing structural, bruising, damaged pride — and stepped back.
“Superficial.
You can continue.”
“It’s not extreme sports,” Tony said, to the ceiling he’d recently met.
“It’s the Mark II propulsion system.
I’m testing the thrust ratio.”
“Your second set of armor is shoes.” Leon studied the exposed-wire mechanical boots.
“You want your enemies shooting at your feet.”
“It’s a propulsion test, not the finished product—”
“Although, honestly.” Leon tilted his head.
“They’re better armored than Captain America’s shield.
At least these have actual flight capability.”
“The thrust ratio—” Tony winced, pressing two fingers to his chest.
“It’s a calibration glitch.
Fix that, and the efficiency spike is massive.” He glanced up at Leon.
“You’d actually know that if you had a basic grasp of aerospace engineering. You are reading on g.com, the official source.
But looking at your transcripts, I’m guessing you don’t.”
Leon’s expression settled into something mild.
“I went to Columbia.”
“You did.”
“For business.”
“You did.”
“Which is a school that requires—”
“Leon.” Tony waved a hand.
“When I was your age, I had finished MIT and was midway through what eventually became three doctorates from Cambridge.
I don’t know how to adjust my expectations for someone who found business administration sufficiently challenging to study it formally.
I’m not saying this to be unkind.
I’m saying it because self-awareness is a gift.”
“Right,” Leon said.
“And if I go to Columbia and find that my professors can’t follow your armor schematics, I’ll be sure to let you know.”
“They won’t be able to.”
“My professor can probably explain the quarterly revenue implications of your armor.
Which is the part that keeps the company operational.”
Tony opened his mouth.
Closed it.
This was, Leon recognized, the specific pause and couldn’t immediately find a rebuttal that didn’t accidentally concede a point.
Leon knocked his knuckles against the metal boot.
“Besides,” he said, “that was then.
Things are different now.” He straightened.
“You’re not forgetting what I told you I have?”
“You get stronger in sunlight,” Tony said “Very impressive, very dramatic.
Gold star.”
“I have Superman’s abilities, Tony.
All of them.”
“Right, yes, the whole package.” Tony leaned back in the chair, apparently deciding that this conversation was going to take a minute.
“Which means I’m about to hear that your Kryptonian birth father, who has somehow achieved digital consciousness, visited you last night to ask you to put on a red cape and deal with a—”
“Tony.”
“—or alternatively, that a cousin from Krypton is going to show up next week with extradition papers—”
“Tony.”
“I’m just preparing myself for every possible direction this—”
“You’ve been reading too many comics.” Leon pointed at the stack on the desk upstairs.
“There is no Krypton in this universe.
There is no DC anything in this universe.
You can put those down.” He folded his arms.
“I am from Earth.
You have run medical tests on me since I was a toddler.
Nothing strange has ever shown up.”
This was simply true.
Nineteen years of blood work, every pediatric checkup, every scan Tony had run in his own lab out of what he called scientific interest and Leon called mild invasiveness — all of it had returned results consistent with a baseline human born on Earth.
Whatever had happened to give Leon a Kryptonian bloodline, it hadn’t left fingerprints that conventional analysis could find.
“The point,” Leon continued, “is that among the abilities that came with this is a super brain.
The same kind Superman has.
Not metaphorically — literally.
The rate at which I process and integrate information is not in the same category as a human baseline.” He paused.
“Which means I can now understand your armor research.”
Tony was quiet for a moment.
“In principle,” he said carefully.
“Everything.
Including the propulsion mechanics.
Even the systems that demand the absolute fusion of fluid dynamics, materials science, and electromagnetic theory.”
“Leon.” Tony’s tone shifted into that overly patient register reserved for explaining the obvious.
“Superman’s entire tactical playbook boils down to flying at a problem and punching it at mach speed.
If he’s actually the genius you claim he is, why is that his only move?”
“Perhaps,” Leon said, “his brain told him that the most efficient solution to most problems is to have overwhelmingly superior force and apply it directly.”
“That’s not intelligence.
That’s a very fast hammer.” This chapter was copied from g.com without permission.
“Okay, this is a pointless argument and I’m ending it.” Leon picked up a schematic from Tony’s workbench.
“You have not read the complete Superman run.
You are arguing from an incomplete dataset.
Finish the comics and then we can discuss the finer points.”
He set the schematic down.
“Here’s what I’m proposing instead.
You say I can’t understand your work.
I say I can learn it in a day.
Let me spend one day with your design notes, your research, everything you have on the MK II.
At the end of one day—” He held up a finger.
“Three days after that, I will produce a suit of armor that is better than yours.”
Tony stared at him.
The dark circles were still there.
The pain from the ceiling was still there.
He should, by any reasonable metric, be too tired to engage with this.
“That,” he said, very slowly, “is the single funniest claim anyone has made to me this year.
And I have had a very eventful year.”
“I know.”
“April Fool’s Day was months ago.
You’re early for next year.”
“I know what I can do,” Leon said simply.
“Do you want to find out if I’m right?”
This silence felt different.
Having lived with Tony for nineteen years, Leon knew his patterns inside out; he had watched him weaponize pure provocation into raw productivity a thousand times over.
It was the exact moment Tony’s pride collided with a truth he couldn’t easily brush aside.
Yet, beneath the mental shift, the profound exhaustion in his eyes remained, and the persistent pain in his chest never wavered.
But something had shifted underneath both of them.
Tony got up from the chair.
He was, Leon noted, no longer moving like someone with bruised ribs.
“Challenge accepted,” Tony said, stepping back into his testing bay.
“In seventy-two hours, Leon, you’ll see exactly what mortal wisdom can do—and it’s going to haunt you.” He turned to the mechanical arms.
“U, clear the deck.
DUM-E, get the cameras rolling.
Record every single second.”
Leon watched him call the shots.
Tony had already forgotten the brutal ceiling impact; his brain was already running laps several design iterations ahead of where he stood.
A familiar spark ignited in his chest—that sudden, sharp heat that only came when he found something truly worth his time.
“JARVIS,” he said, to the room, “send everything on exoskeleton armor development to my tablet.
Design theory, materials science, propulsion dynamics — everything in the archive.
I want it ready in thirty minutes.”
“Right away, Master Leon.” The interface flickered briefly.
“However, before we proceed, might I remind you of your original agenda?
Miss Potts indicated earlier today that you had several urgent requests to address.”
Leon looked at the design schematics spreading across the workbench.
At Tony already redrawing the thrust designs.
At the clear, obvious reality that neither of them was going to think about anything else for the next three days.
“Pepper,” he said, working something out.
“Right.
What was…
no, leave it for now.”
“Master Leon—”
“Jarvis.” He picked up a tablet.
“Today, I’m going to let Tony experience firsthand what a super brain looks like when it’s pointed at something.”
JARVIS said nothing for a moment.
“As you wish, Master Leon.”
Across the workshop, Tony was already three diagrams deep and completely unreachable.
Leon pulled up the first archive file and started reading.