Summary: Instead of stopping when seeing an image of his mother, Jin decides not to hold back. Where he, in his devil form, finally kills Heihachi and Kazuya once and for all with his bare hands. With that victory has some consequences in regards to both their deaths and dealing with other threats.

Universe: Canon-Divergence from the end of Tekken 4 onward.

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A/N: Just a disclaimer in regard to this series lore and how convoluted it can be, as well as the characters covered in plot armor, this is made in the sake of a What If scenario. Not at all is it meant to turn some well deserved attention to the other great characters in this series. Honestly if I had to choose, King is my favorite if just because he's a Mexican wrestler who speaks in growls. In no way is this supposed to say Jin is the strongest as there's other stronger ones than the Mishima family outside the Devil Gene like Lars, Heihachi, and of course Paul Phoenix.

This is made just for the sake of argument regarding how it may go in my mind, and keep in mind all graphic depictions are for an older audience and how I think it fits the series that frequently has a family throw one another off cliffs or into volcanos.

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It would be so easy...

"Nnnghhh..."

His father was on his back, unconscious and his grandfather held up by his neck, weakened and ready to accept any fate he so rightly deserves.

"DO IT BOY... KILL HIM AND KAZUYA..."

Deep in the back of the mind to that of one Jin Kazama thought darkly, speaking like the devil as the young fighter glared right down at his grandfather. For years he's dealt with the man and his evil, just as much as the rest of the world has with him just ready to laugh it off. Not too far from the devil like man was an equally as dangerous man on his back with a large scar across his chest. The man didn't need to be in Jin's life at all and only cares for himself, the boy having no compassion or love to him after that.

Kazuya and Heihachi have warred with one another for literal decades and so many lives ruined because of it.

'I could end it.. right now...'

And Jin, the boy who had no part in this minus the blood he shared with them, had them right where anyone could want them.

Unconscious or severely weakened, ready to put on any form of punishment and Jin ready to assert himself by his own, clawed hands. Growling, Jin hoisted his grandfather up higher, Heihachi grunting as he felt himself held up higher, his feet now odd the ground and dangling in the air. Heihachi growled as he punched and tried to pry Jin's clawed grip from his neck, the devil man keeping it strong.

"Y-you can't... do this..." Heihachi barely gasped out as his grandson growled harder, "Y-you could never... b-be strong enough..."

'He tries to insult me... despite all he did?!'

Images of his first win of the King of Iron Fist Tournament rang through his head as he recalled the victory he took over Ogre. Instead of congratulating him on his victory, Heihachi instead had him shot up by armed guards, the final shot from the old man himself. How he knew from that moment he would never care for the man or all he stood for, which was more proving himself the better to everyone else.

"J-Jin..." Weakly, Heihachi tried to reach forward and grab the boy's face, the devil man frowning as he tightened his hold once more.

SNAP!!!

A strong, quick jerk of his wrist snapped the man's neck as it fell to the side against his grandson's clenched hand. Jin himself growled as he felt the man grow limp in his hold, as well as his breathing stopping against his palm. Shaking him, he made sure the man was dead in his hold as he's been fooled before in thinking he's dead. Pulling his head closer, Jin stared down the man's eyes, rolling to the back of his head, paled and without any light.

CRASH!!!!

Either way, the man was gone so Jin had no further need and tossed him right into the side wall,  spiderwebbing around it before falling limp forward. Him taken care of, Jin turned his attention to his father, no, that title wasn't deserved to the man, as Jin stomped closer. He just killed his grandfather in cold blood, showing no remorse for it, and was ready to end the legacy of his father.

'You don't need to do this..'

The one voice of reason in his mind spoke as he stomped closer to Kazuya, trying to reason with Jin in hopes of sparing the pain. Only thing was that he would be spared of even greater pain if he doesn't hold back and take down both the world threats. Anything in forms of remorse he may feel were so weak to defend for either men as Jin cycled through his memories.

Heihachi?

Sure the man took him in when his mother was gone, but the man saw him only as a tool, nor once cared for his feelings. Even when he go strong enough to avenge his mother, the old man shot him down with his own gun, proving he never cared.

And Kazuya?

The first time he actually meets him in person is being strung up by chains, intent to kill him and take back what was his. He didn't care for his bastard of a son, and Jin felt the same could be said for his own mother, who he never bothered to see after he was born.

C-crack...

Jin growled as he clenched his elongated teeth together angrily with his knuckles cracking from how strong his grip was.

"NNGH..."

Slowly, Kazuya opened his eyes, greeted by the silhouette of his own son peering down at him, his own wings giving the visage to the Angel of death.

SLAM!!!

"NNGH!!!"

Kazuya barely raised his arm before Jin's boot slammed down hard against it, pinning him down with his knee to his chest. Leaning down closer, the man could see the devil in his eyes with his own laser ready and willing to fire. Had the man cared in any way, he would have actually been proud to see Jin summon the devil.

"Hmph, still so disappointing..." Kazuya said lowly as Jin growled lowly, the man still smug and arrogant despite his position.

"Even now, you can't face me like your original self, instead using a power I wield." He added Jin grew even angrier.

Kazuya could see the anger and know that the boy wasn't ready to play around, and knew just how to work with that. Regardless the situation, the inherited devil man will stop at nothing to get what he wants and some brat he spawned will not get in his way. Unseen by the younger Kazama was the dark, devil aura forming in Kazuya's hand, ready to show the boy a proper rematch.

SWISH!!

Raising a brow, the man saw Jin raised his clawed hand up while keeping the glare up as he did.

"What? You going to kill me? You don't have the guts, you never will." Kazuya continued egging on as Jin glared more.

GLOOOOOM....

All while the Devil's aura grew more wild between the two, Jin more wild and Kazuya's more controlled, but just as deadly. Kazuya didn't want to waste any more time with the boy and get back to kill his father, going back to his original plans, and won't have any random brat-

SHING!!!!

"GAH!!!"

In a swift movement, not giving Kazuya any time to recuperate, Jin plunged his hand right down and through his chest. Clean through the very scarred tissue with his clawed gloves, Jin pierced the skin and went in deep. As he did, he was far enough that his full hand was inside Kazuya's chest and past his ribs, shattering like glass.

Ba-bump...Ba-bump...Ba-bump...

'Hmph, surprised he has one...' Jin thought faintly when feeling something bump against his hand.

Kazuya meanwhile was mostly stunned by the sudden attack, looking down and seeing his own son's hand actually cutting his skin. The man himself had been apart enough battles to know the sting of bruises and scrapes all over his body, the scar itself example of that. This however wasn't something he expected, least of all by his own son, who he assumed was too soft to try.

Drip drip drip drip~...

Off the sides of the wound, Kazuya felt his own blood drip out, him trying to pull Jin's hand out.

TUG!!!

"G-GAH!!"

But retracted when feeling something pulled alongside it.

"Do that and I'll pull out your heart..." Jin spoke darkly as he looked at the struggling man's face, who bit his lip hard enough to bleed.

"Y-you think you can k-kill me... boy?" Kazuya gasped out, spitting blood to the side of his face, Jin squinting his eyes, "N-not even that old b-bastard could... y-you're no better..." He said with a few gasps as Jin scoffed.

Carefully, Jin stood up on Kazuya's sides, his grip still like iron inside the man's chest, Kazuya grunting hard in pain. At full height, Jin kept Kazuya up like a reverse puppet and the blood dripping down his pants and to the floor. Now in that position, Kazuya tried more than ever to break free of his son's hold, painful grip he damned if to get free.

"It killed him well enough..." Jin said, looking to the side with Kazuya following to see what he meant.

!!!!!!!

And Jin could actually feel the man's heart freeze against his grip when seeing the old man laying in a heap of rubble on the floor. While this was no different to other times he'd taken Heihachi down himself, it was the angle at where he laid. Sprawled out on his upper chest, his head laid on an angle to better show just how mangled Jin left his neck, snapped in two. No matter how tough the man was, that strike would kill any man with his spine no longer connected to the rest of his brain.

"Y-you..." Kazuya said while staring at his dead father's body.

"So easily."

Kazuya looked back at him in shock, the boy keeping him up to show how this was still serious, his son's hand penetrating his chest.

"Don't worry..." Jin began as Kazuya growled and tried to get free.

"You'll be joining him soon..."

SQUELCH~!!!!!

A foot to the chest and grip still up, Jin harshly pushed Kazuya forward, his back harshly hitting the adjacent wall hard enough to make a dent. Blood was flying around when he sailed from his son's outstretched hand to connect the two right in place. In Jin's soaked hand laid Kazuya's own slightly beating heart if just faintly holding on with what little connection it had.

Kazuya meanwhile was left so short short of breath he felt as though he was hyperventilating in both his growing hysteria and pain. Down he saw a clear hole in his chest, blood still pooling from it and onto his lap in growing quantities. Weakly, he raised his hands to try and block the streak, his mind too lost for what to do next in losing such a way. In front of him, he saw his own son, the man who left him like this, holding his heart in front of him like it was a precious gem.

"You know, I once dreamed of meeting you..." Jin began as Kazuya tried and failed to push himself up, his strength leaving his arms.

"That once I did, I would make you proud and you and my mother would be a happy couple, no worries and no more hurting..." Jin continued as he stepped closer, Kazuya already having his back to the wall and couldn't back away anymore.

Squish~!!

Kneeling before the man, he held the heart that lost more and more movement in his grip to the lost of it's remaining ounces of blood. The seasoned fighter didn't know what to do, having not felt this weak and helpless since the fight that began his path of revenge. He tried and tried, but he couldn't summon the power of the devil, feeling nothing but a cold emptiness inside. All that was there was the growing fear of his own son, staring at him with a look that told him one thing.

"But now, I'm ending this, once and for all."

He was going to die that night.

SLAM!!!!!

SQUISH~!!

Once again the former devil man couldn't anticipate Jin's fast fist right to his face with the heart right against it as well. And like before, it didn't just break his bone, it went clean through his face and into the wall from behind. The rest of his body slumped, limp under the brutal attack with Jin let out a small, faint growl from the brutal take down.

GLEAM...

"N-Nnnghhh..."

However a new pain shot through his body, the dark purple aura spread from both their forms as it almost joined from his father's corpse to his own hold. Growing stronger and more deadly, Jin felt as though the evil inside him grew stronger, a deep spiritual grin tightening on his soul. As he felt the power transfer, Kazuya's body slowly grew thinner, like all that kept him alive originally was completely gone. Around him the demonic traits he carried grew more wild, extended past his forearm to his shoulder.

S-SHINK!!

The horns grew sharper with a few extras around them and soon the rest of the sides to his head, piercing out of his skull. His skin grew even more grey, hardening like steel like his gloves, which were more gauntlets now med of metal. Added to that, his feathered like wings were sharper, longer, even with a wider wing span then before. All his breathing became more ragged and beast like with how different he felt, all his teeth sharpening like knives.

"GRRRRRR..."

Growling, he started down at his blood soaked, demonic hands and claws like miniature knives, feeling even more angry then before with the power overwhelming.

[There should be a GIF or video here. Update the app now to see it.]

R-R-RUMBLE!!!!!

Around him the entire temple rumbled from the sheer force of his yell was strong enough to damage it even greater than before. Around him the rafters and ceiling fell and covered Heihachi's body with Jin giving his father's body one last look.

BOOOM!!!!

Till he shot up high and straight through the collapsing ceiling, causing a greater hole in the building as, with a single leap, he was now in front of the moon. Wings extended out, he appeared almost like a demon rising from the depths of Hell brought to bring chaos onto man. Jin himself couldn't even control himself as he soared through the skies, his wings shooting him faster than a small jet.

With what little conscious mind he had left from his fly away, he could only think of one thing;

'What... have I done...'

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A/N: Before anyone starts on the whole "that was dark", "he couldn't have killed them so easily", or "why remind us of Blood Vengeance", let me explain.

This, again, is made as a massive "what if" scenario of what could have happened and, if I decide to make it a full story, would greater lengthen this and any other concepts I make. Better explain the situation, as well as how easily Jin could have killed either if he decided not to hold back and let the devil take control.

Irregardless, I hope you enjoy.