In two or three fics I've read about this scene (for those who want to take credit for the idea step up) and how it changed Harry but everyone just puts it in as a trivial fact and doesn't put it in as a major part of the plot. So I am going to attempt. Oh and I'm probably going to alter the scene a bit.
Oh and this belongs to J.K. Rowling not me.
Chapter one: Change Hurts
The memory of a most vile man taunted a young boy as he flung curse after curse at him, distracting the child from his fight with the giant beast known as a Basilisk; a giant snake that served under one of the four founders of the school they fought in, Salazar Slytherin.
At one point the bird who brought the boy the sword flew into the path of one of the killing curses he flung at the boy, shielding him from the damage but mortally wounding it's self. It landed in a bloody pile by the girl the boy was so desperately trying to save.
"No!" the boy yelled looking down towards his fallen friend, leaving himself open for the fangs of the beast to dig deep into his arm and push it's vile poison through him. He let out a scream of pain but still managed to push the blade of the sword through the beast's mouth and into its brain.
The creature let out its own shriek as the pain came but it refused to let go of its pray, wishing to take him down as it fell. Its body spasmed as it died, collapsing near its soon to be ex-master.
The man in question looked at the dying beast as though he were watching a pair of shoes get scuffed; annoying but no matter. "So this is the end of the great Harry Potter, the boy who defeated the older me when he was just a baby. Writhing in agony as death quickly sneaks up on him."
The boy in question was currently hobbling over towards him and the girl in pain, holding the broken off fang that was embedded in his arm. Harry fell to his knees in pain but still bent over to check if his friend was alright. When he touched her, his worry increased. She was cold, almost too cold for someone living.
"Isn't it funny what a book can do in a stupid little girl's hands?" the memory said as he walked over raising the wand he had stolen from Harry, preparing for another spell. But the look of pure rage crossing Harry's face as he pulled the diary from the girl's hands made him pause.
"What are you doing, Potter?" the man snarled as he lifted the wand up again but this time his arm visibly shook in what could be fear.
The boy said nothing as he continued to glare at the man and raised the fang he held in his hand high into the air. He then plummeted the fang into the book as hard as he could, making the ink bleed out of the hole he made.
The memory dropped the wand in pain as a light erupted from his belly and started to spread to his arms as Harry struck the book with the fang again. The memory left in the diary tried to move forward but Harry launched his final attack. Piercing the book from cover to cover, the ink blood poured out and the memory staggered forward as it dissipated in a blast of light.
With a sigh of relief, Harry fell back in pain as he felt the poison spreading through him. He could almost laugh right then; his crappy childhood was finally coming to an end at the one place he actually considered home and felt safe staying at; a place where he could finally be himself and make some friends. Mind you it was still hard with the fact that he was famous and, of course, his new found ability to speak to snakes; but he still managed to make some real friends, friends that he risked life and limb with, twice, against the same man.
Besides if he was going out, he went out with a bang, seriously, how many people could say they fought and won against a few centuries old Basilisk; one who's blood he was now laying in a puddle of; gross.
He stopped his musing when he felt something crawl onto his chest. Lifting his head up to look, he noticed the bloody Phoenix who helped him earlier crying, its tears dripping onto the puncture wounds, healing the flesh and lessening the pain a bit. But there were too many places for the bird to reach in time and they both know it. "Thanks for trying, Fawkes but it looks like it's the end for me. I did put up a good fight though, right?"
The bird nodded its head a few times, letting a few honest tears fall from its eyes as it watched the boy lay back down in the pool of blood. The bird did not want to see such a boy die so young and tried something it had never done before, something it did not know the consequences of. It started its cycle of rebirth and forcibly dragged Harry in with it.
The bright fire burned, engulfing both Fawkes and the blood covered Harry into its embrace. As they turned to ash, Fawkes worried that its plan wouldn't work and would just leave Harry as a pile of dust. But its worries were for nothing as it watched Harry reform out of the ashes with it.
Its young form screeched happily on the now naked boy's chest but noticed something was wrong. He was whole but something was off, really off. The phoenix wished it could be older and fly or teleport to get help but at its fastest it would take two hours to reach that state.
Thankfully that young witch was coming to and she might be able to do something. Okay no, all she did was scream, blush and faint. All they could do is sit and wait.
It took two hours but Fawkes was finally a decent enough size to fly and carry people with him. He picked Harry up using one of his tail feathers and grabbed the girl in one of its claws. The bird used its flaming teleporting ability and appeared inside the schools medical bay, where Madame Pomfrey and Headmaster Dumbledore were waiting.
"Ah, Fawkes," the old man said in a cheerful tone, before taking a grave look at the two children it held. The nurse instantly rushed over to the children, giving each a thorough examination. While Madame Pomfrey examined the two, Dumbledore spoke to his familiar, "I do believe that there were two others that went with them."
The bird just shrugged its wings and kept an eye on the now hospital gown clad Harry. "I do believe it would be wise to pick up Mr. Weasley and Professor Lockheart." The bird gave a weird look to its master, saying that it wanted to stay but it soon let out a defeated sigh and left.
After a few minutes, Madame Pomfrey declared that Ginny would be well after a full nights rest and moved on to Harry. She made a swipe of her wand and the tip glowed a healthy green. The nurse dragged her wand over Harry's body, examining it for any abnormalities. And it took all of six seconds before she let out a yelp of surprise.
"This isn't right. Albus! This isn't right. There is something wrong with Potter!"
The headmaster rushed over with a worried look on his face "Is he ill?"
"No he's perfectly healthy, even in better shape than when he arrived here first year."
"Than, what's the matter?"
"My scan shows that his skin can't even be counted as skin. It's a mesh of tiny scales and his hair is made of incredibly thin feathers. His body temperature is at 43oCelsius and he isn't burning up, his body is reacting as though this is his normal temperature. The scan says barely even human. Something has changed him, at a genetic level."
The headmaster stroked his beard as he tried to control his own emotions. This whole year was filled with shocking events. First his students were being petrified, then someone wrote on the walls, claiming that the 'Heir of Slytherin' had returned meaning the chamber of secrets had been open, after that, one of his students gets taken to the chamber, and now he had this, perfect. "We will have to wait for young Harry to wake up before we can tell what happened; maybe young Miss Weasley has an idea."
Poppy then turned to the bed where a groggy Ginny Weasley had woken up "Where am I?"
"The hospital wing, dear. Can you tell us what happened?"
"I don't know. Everything for last few months is a little hazy. A diary, a big snake, a chamber and….Harry! We've got to help Harry!" Ginny yelled as she sat up to rush back to the chamber to save her own savior.
"Ginny, dear, calm down, Harry is alright, just unconscious. Your parents should be here soon," Madame Pomfrey said before bringing her attention back to the poor boy that was still sound asleep in the hospital bed. "What do we do, Albus?"
"We wait. We wait for our young friend to wake up," Dumbledore said as he walked out of the room to announce the news to a wary school.
A week later Harry Potter finally opened his eyes.
I hope you guy's liked that, oh and applause for my new Harry Potter beta 'Slytherin's Silver Dragon'. She made sure I did everything right.