Summary

Killian's death was supposed to be the end, but when Tony discovers Bruce has been injected with Extremis virus he realizes things are far from over. As Hulk and Extremis battle each other for control of Bruce's body, Stark must help Banner through his toughest challenge yet.

Author Note

This story is set after and during Iron Man 3. This is the most excited I have ever been about any of my writing, I'm quite proud of this one so I really hope you enjoy reading it as much as I did writing it. Here is a short prologue to give you a taste : )

Playing with fire

Prologue

Tony Stark let out a huge sigh of relief as he took a long glance at the charred human remains that were scattered across the ground. He wrinkled his nose in disgust when he noticed that the ashes were still hot and smoking, but there was no doubt about it;

Aldrich Killian was dead.

'My apologies sir, but I must inform you that there appears to be one remaining Extremis heat signature within your proximity.'

'Gotcha!.'

Stark spotted a moving figure out of the corner of his eye, he turned quickly on his feet, thrusting the gun in his hands forward threateningly.

'Show times over pal, might as well show yourself!' he called to the shadowed figure hidden amongst the rubble.

He turned sharply as his words were answered with a rustle of movement. In the far corner of the room beneath a cave in wall was a pile of rubble and twisted mangled metal, the whole room was littered with bricks and dust.

'Sir I –'

'Not now Jarvis I'm busy!'

There was another loud groan and the pile shifted, causing more debris to fall to the floor. Despite the bad light Tony could make out a dark silhouette.

'Put your hands where I can see em or I'll put a bullet in your head.'

'Sir the heat source is showing unusual readings.'

The billionaire didn't answer, instead he inched forward, and his attention was focused on the shadowed body in front of him. As the lights flickered all he could see clearly was an exposed leg, torn pants were cut off at the ankle, exposing a bare foot covered in dust and bruises. There was another cry of pain as the figure struggled and twisted its body, squirming like a trapped animal.

'Sir the subject is not pure Extremis, I'm detecting an unusual reading, I strongly advise you to-'

'Jarvis mute.'

'Tony I-'

'Stay back Pep, I got this.'

He growled in frustration and kicked the leg sharply.

'Time to say goodbye pal, games ov-'

His words were cut short when the lights suddenly flickered on, illuminating the figure in front of him. Stark let out a gasp as his eyes locked on the writhing man on the floor.

'Holy shit' he breathed, the gun is his hands dropped to his feet when a familiar pair of brown eyes flickered open, unfocused in a pained daze of confusion.

The man shuddered for a moment as his trapped limbs spasmed uncontrollably; a pained cry escaped his throat as he tugged at them in desperation, his short curly brown hair stuck to his sweat ridden face as he panted in exhaustion.

'Tony?' Peppers whispered went unanswered as the genius fell to his knees.

Tony had to fight hard to repress the sick feeling in his stomach as his eyes took in the sight of limbs tinged with red and green.

'B-Bruce?'