Karl switched off the television.
George Stacy's situation no longer concerned him. In the grand scheme of things, it was nothing more than a ripple — one that would fade quickly in a world filled with far greater crises.
Just as he began considering his next move, his phone rang.
Tony.
Karl answered.
"Hey, buddy. Enjoy the excitement last night?" Tony's voice came through, full of amusement. "Hahahahaha."
Karl's tone turned flat.
"That must have really provoked you, having guns pointed at your friend's head. Want to try it yourself? I can arrange it. I promise they won't accidentally fire."
"Jesus— alright, never mind," Tony coughed. "Are you satisfied with the result?"
He paused, then continued.
"By the way, Yinsen says the gene research is finished. He couldn't reach you. Where the hell have you been all day? You weren't…?"
"Shut up," Karl cut him off. "Let's go take a look. I'll also introduce you to a big guy — someone who can stand toe-to-toe with the Hulk."
Before Tony could reply, Karl hung up.
Tony Stark was many things, but tactful was not one of them.
Bringing Juggernaut to the Lab
Karl entered the detached residence where Cain Marko was staying.
Moments later, the Juggernaut stepped through the Shadow World with him, emerging inside the biological research facility.
They arrived almost instantly — far faster than Tony could travel even in his Iron suit.
Juggernaut looked around with mild disinterest.
"Thought we were fighting."
"You might later," Karl replied.
The Lab
Karl approached Yinsen.
"Yinsen, how did it go? Have you conducted human trials?"
If the serum was to be used on Aunt May and the others, safety was paramount.
Yinsen turned, smiling.
"Carl — you're here. Yes. I tested it… on myself."
Karl blinked.
Only now did he notice.
Yinsen looked twenty years younger.
His posture was stronger. His complexion healthier. His eyes sharper. Even the subtle tremor in his hands was gone.
He looked like a man restored to his prime.
"My recovery speed has improved," Yinsen continued. "Metabolism enhanced. Cellular degradation slowed. To a significant degree, it may even extend lifespan."
Karl frowned.
Anger flickered across his face.
"Yinsen… why would you experiment on yourself?" he said sharply. "If something went wrong, we couldn't undo it. Genetics isn't a broken bone you can reset."
He exhaled slowly.
"There are death-row inmates Tony could legally access for trials. What you did was reckless."
Yinsen was momentarily stunned.
Then warmth crossed his expression.
"I… was impatient," he admitted. "Samuel and I verified stability multiple times. I'm fine. Better than fine."
Karl's expression softened.
"Don't do it again."
Red Room Genetic Data
Karl retrieved a data drive from his system space and handed it to Yinsen.
"I obtained genetic enhancement data from the Red Room — the modifications used on Black Widows. See if you can integrate it."
Samuel Sterns immediately snatched the data tablet.
"Boss… this is extremely similar to our base sequence," he muttered rapidly. "But key regulatory segments differ. If integrated correctly, the genetic expression could be significantly improved."
His enlarged cranium twitched slightly as his mind raced.
"I already have a pathway hypothesis."
He rushed back to the workstation.
Yinsen chuckled.
"That's Samuel. When it comes to genetic science, the man forgets the rest of reality exists."
Karl smiled faintly.
Nearby, Juggernaut slumped onto a reinforced couch, staring blankly at the ceiling.
He looked deeply bored.
He would have preferred a battlefield to a laboratory.
Tony Arrives
The lab doors slid open.
Tony Stark entered in a tailored suit, pausing mid-step.
"Holy hell… that guy is built like a tank."
He stared at Juggernaut.
Juggernaut waved a chicken bone.
Tony blinked.
"…Okay."
Karl spoke calmly.
"The experiment succeeded. Yinsen used himself as the test subject. I also brought enhancement data from the Red Room. Samuel is integrating it. If successful, this will surpass our current gene platform."
Tony's expression darkened.
"Yinsen… you tested it on yourself?"
Concern replaced irritation.
"You should've told me. Human trials can go wrong fast. How do you feel?"
"I'm fine," Yinsen laughed. "Stronger. Younger. Healthier."
Tony exhaled slowly, then clapped him on the shoulder.
"Don't do that again."
Breakthrough
Samuel suddenly shouted from the workstation.
"Boss! Alignment complete! The gene sequences are compatible!"
Karl, Tony, and Yinsen approached.
"If expression stabilizes," Samuel continued excitedly, "the enhancement could approach Super-Soldier Serum performance levels — though without access to Erskine's original Vita-Ray activation method, exact equivalence cannot be confirmed."
Karl nodded.
"Let's synthesize it. Test on mice first."
Samuel and Yinsen worked together.
Within minutes, two vials of serum were produced.
The solution carried a faint metallic sheen — bioactive nanoprotein clusters suspended within the medium.
They injected a lab mouse.
The animal remained calm.
Then—
CRACK.
The mouse struck the glass wall.
The reinforced container fractured.
Tony stared.
"…That mouse just bench-pressed its enclosure."
Karl used telekinesis to gently capture the mouse and transfer it into a bulletproof containment chamber.
No signs of aggression.
No neural instability.
Just enhanced strength and vitality.
Karl picked up one vial and activated system analysis.
[Super Gene Serum]
A biological enhancement serum derived from hybridized genetic augmentation formulas.
Effects include:
• Enhanced physical strength and endurance
• Slowed cellular aging
• Accelerated metabolism and recovery
• Strengthened immune response
• Comprehensive enhancement of six core physiological attributes
No mutagenic instability detected.
Karl lowered the vial slowly.
No abnormalities.
No corruption.
No instability.
This meant…
It was ready.
And for the first time, a gene enhancement existed that could rival the Super Soldier Serum — without its fatal failure rate.
Karl's eyes gleamed faintly.
The future had just changed.
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