The lab smelled of burnt circuitry and wounded pride. Leon found Tony sprawled beneath a scorch mark on the ceiling, one mechanical boot still sparking.
"Rocket shoes?" Leon nudged the smoldering footwear with his toe. "Didn't peg you as a Back to the Future fan."
Tony batted away the foam from Stark Industries' overzealous firebot. "Thrust vectoring prototype," he grumbled, prodding a bruised rib. "Needed baseline data for the Mark II's stabilization—"
"By using yourself as crash test dummy?" Leon hoisted him onto a hydraulic lift. "Remind me why we fund MIT when geniuses learn physics via concussions?"
Tony's glare could melt tungsten. "Says the human solar panel who thinks 'super-brain' means acing community college algebra."
The gauntlet thrown, Leon's eyes flickered with crimson amusement. "JARVIS, pull up schematics for all Stark propulsion systems. Let's educate Mr. 'Three PhDs Before Puberty.'"
Holograms bloomed – repulsor blueprints, ion drive equations, even a rejected design for rocket-powered rollerblades. Leon's pupils dilated as solar-charged synapses fired.
"Ah." He tapped a flawed torque calculation in Tony's latest design. "You're compensating for lateral drift with... prayer?"
Tony snatched the hologram. "That's a harmonic dampener!"
"Which fails above Mach 2." Leon scribbled corrections in midair, equations glowing like arc reactor plasma. "Add a gyroscopic array here, recalibrate the—"
"Stop." Tony's wrench clanged against the workbench. "Since when do you know Navier-Stokes equations?"
"Since my cells started photosynthesizing calculus." Leon tossed a graphene sheet into the molecular printer. "Your turn. Explain why your stabilizers resemble a drunk hummingbird."
The challenge hung like shrapnel in the air.
By dawn, the lab resembled a MIT hackathon gone feral. Tony's coffee mug now held liquid nitrogen. Leon's left boot had been repurposed as a flux capacitor prototype.
"Sir," JARVIS interrupted as Leon welded a titanium exoskeleton with his heat vision, "Ms. Potts has called seventeen times regarding the Osaka shareholders—"
"Tell her we're revolutionizing personal transportation!" Tony shouted over the plasma cutter's whine.
"And curing male fragility," Leon added, eyeing Tony's latest boot design. "Two birds, one super-sonic stone."
The AI's sigh manifested as a system-wide voltage dip. "Shall I prepare bankruptcy filings alongside the press release?"