Firestarter

Alps, SHIELD Base Echo-9 – 0700 Hours

Snowfall muted the distant rumble of an incoming storm.

Not thunder.

Engines.

Y/N stood at the base of the valley, armor sealed, reactor steady, eyes cold. She hadn't slept. She didn't need to. The fire inside her now was its own fuel — all memory, rage, and clarity.

Next to her, Loki twirled his scepter once, calm as ever.

"Are you ready for this?" he asked.

"No," she replied. "But I'm doing it anyway."

He smiled faintly.

"You make a beautiful heretic."

Avengers Quinjet – Inbound, 0702 Hours

"They're there," Hill confirmed over comms. "Perimeter scans picked up Stark's arc core. Full charge. She's not retreating."

Inside the jet, Tony checked the diagnostics on his suit. The new one. The one he never thought he'd use against her.

Steve readjusted his shield. Bruce had already pre-dosed himself to let the Hulk out without resistance. Natasha loaded her last clip, lips tight.

"You think she'll talk?" Clint asked.

No one answered.

Because they all knew:

Y/N wasn't here to negotiate.

SHIELD Base Echo-9 – 0705 Hours

The first explosion took out the west tower.

Loki's magic surged upward in a cascade of green fire, laced with something darker.

Y/N moved fast, ripping through the outer gate with her gauntlet's newest pulse mod — an oscillating frequency she'd designed to destabilize vibranium structures.

The doors shattered inward.

SHIELD guards scattered. Some raised weapons. Most froze.

Y/N didn't fire.

She walked through the smoke like it didn't touch her.

"Facility Echo-9 is in breach," a voice screamed over comms. "Repeat—"

Then the speaker sparked, shorted, and died.

Inside the Control Room – 0710 Hours

She found what she came for in the third vault.

Files. Coded storage capsules. Black box tech she'd designed before they benched her. Before they called her a liability.

She keyed in her override. The vault opened with a hiss.

And there it was: a prototype AI drive — early-stage Stark tech, modified for threat prediction, tied to global surveillance.

She picked it up slowly.

"They weaponized my mind."

Loki stepped in behind her. "They always do."

She pocketed it.

"They're going to come through the sky," he said.

"I know."

She turned toward the ceiling as the first low whine cut through the storm.

"And I'm going to meet them there."

Above the Facility – 0715 Hours

The Avengers' jet dropped fast.

Too fast.

They weren't planning to circle.

They were landing to end this.

Tony stepped out first, repulsors flaring.

Steve followed. Then Bruce — already shaking, the green surfacing in his veins.

Natasha and Clint moved in sync, silent and sharp.

They found her at the base entrance, cloak whipping in the snow, violet arc core flaring like a beacon.

"Y/N," Tony said. "Last chance."

She didn't respond.

"Step away from the facility," Steve said. "And we talk."

She looked at them all — the people who trained her, fought beside her, loved her.

And said nothing.

Instead, she raised her gauntlet.

Fired it straight into the snowbank beside them — a warning shot, calibrated to shake the earth, not maim.

The message was clear.

Come closer and you burn.

The Fight – 0718 to 0730 Hours

Bruce transformed mid-step.

Hulk charged.

Y/N waited.

Then dove to the side, firing a kinetic shockwave that sent the Hulk skidding into a collapsed wall.

Steve ran in next, shield raised.

She met him blow for blow.

Each hit cracked the ground, each deflection sparked light off her reinforced gauntlet. He was stronger. She was smarter. She used terrain, misdirection, aerial propulsion — a fight built on muscle vs. mind.

Clint circled above, targeting her with stun arrows.

She caught one in midair.

Threw it back with a flick of her fingers.

Natasha flanked — fast, brutal.

Y/N barely ducked the first strike.

The second scraped her armor.

The third never landed — Loki intervened.

He grabbed Natasha's wrist mid-swing and twisted.

Not enough to break.

Just enough to warn.

Tony hung back.

Watching.

Waiting.

Until the rest were down.

Then he stepped forward.

"Y/N," he said again. "It doesn't have to go like this."

She was breathing hard now. Not tired. Alive.

She stared at him.

"You used to call me your legacy," she said. "Then you called me a mistake."

"I never said that—"

"You didn't have to."

He raised his hand.

So did she.

"Don't," he whispered.

But she already had.

The Final Clash – 0731 to 0735 Hours

Her blast collided with his midair.

The shockwave cracked the ice beneath them.

They flew at each other — repulsor vs. repulsor, father vs. daughter.

They clashed midair, skidding across broken terrain.

He fired. She dodged.

She fired. He absorbed.

They fought like they'd built each other — and in a way, they had.

He was stronger.

She was faster.

He hesitated.

She didn't.

Ending the Fight – 0737 Hours

She had him.

One knee on his chest, gauntlet charged, arc flare pressed to the core of his suit.

He stared up at her.

And saw her — not as the girl in his lab.

Not as the daughter who hugged him after every mission.

But as something other.

A weapon he hadn't tempered.

A wildfire he'd tried to cage.

And failed.

She panted.

He didn't speak.

"I didn't want this," she said.

"I know."

"But you made me this."

He closed his eyes.

"I know."

And she stepped back.

Aftermath – 0800 Hours

The SHIELD base was empty now.

Files gone.

Weapons dismantled.

Y/N stood at the edge of the crater that used to be Echo-9.

Her reactor hummed soft.

Loki stepped beside her.

"They'll regroup."

"I know."

"They'll retaliate."

"I hope they do."

He watched her for a long moment.

"You didn't kill them."

"No," she said.

"But they'll know I could have."

Avengers Compound – 0930 Hours

The team sat in silence.

Everyone was alive.

But it felt like they'd lost.

"She didn't take the shot," Steve said quietly.

"Doesn't mean she won't next time," Natasha said.

Tony stared at the floor.

Not speaking.

Because his greatest creation had just walked away again.

And this time...

...he didn't think she was coming back.