There were chances in life, odd bends of fate that caused things to go one way sometimes, and other times they went in the opposite direction. Sometimes those changes are massive, with entire armies falling in battles they rightly should have won. Other times, those changes are small, when a butterfly flaps its wings at the wrong time, causing an eye to move away, just before they would have seen the face of their one true love.
Sometimes though, a small change, can make big things happen. During an era called the Third Shinobi World War, a man was left adrift. His village, one that had been dwarfed by strong neighbors, was destroyed in an attack. The elders laid dead at his feet, the attacks fleeing into the rain, leaving the man alone to mourn. A hastily dug grave served to cover the bodies of his fellows, and he was left with a choice. One he chose to leave up to a coin.
In most times, the coin came up tails. Thus he would go north, and offer himself to the Tsuchikage. The Kage, seeing a man with a bloodlimit that might be useful as the war dragged on, took him as a mercenary, giving him many missions. These tasks he fulfilled with the strength of his heritage, cutting down swaths of enemies, crushing resistance beneath his power, blowing away whole legions, only to vanish in a flash.
The war ended, and the man was now bitter, alone, and very much old. So when an assignment came to patrol the borders of the Land of Fire, he took it. He then found a patrol from the other side a bit too far on the Rock side of the border, so he struck, slaying one of the three, and injuring another, leaving him alone against a blond haired man, who had claimed to be returning home to see the birth of his son. The man from Rock battled him, and injured him, before falling to the Yellow Flash, dying unmoruned in the forest.
The injuries he inflicted may have been something greater than most would know, as the delay kept the Yondaime from his village, and when a seal was broken, his speed wasn't what it should have been, so a great monster was able to close with the village, and many lives were sacrificed upon it's claws. A seal was made, and a life was begun that would lead the world through a war, and show all a path that was different.
But sometimes, a change can happen. In some times, the coin came up heads, and the man instead went south, his blood limit a boon to the Village Hidden in the Leaves. Instead of the coldness, the man found warmth. Instead of being alone, he found a friend, and then a love. A woman who, nine years after he had arrived, had their child. Tragedies can happy in the midst of miracles though and she passed giving birth to the next generation.
Then a seal was broken. A woman in a cave far from the village cried out, and something came from within her. It's power was overwhelming. It was opposed by the Man however. He had aided the Yellow Flash of Konoha, and the two stood before the thing, staring at a mountain of red fox, which growled down at them. Both saw the hate that filled those eyes, and neither moved, as they prepared to defend their home.
"Minato!" shouted Hiro, as he leapt into the air. His feet seemed find purchase even in open sky as he moved like a red rocket, slamming hard into the paw that had been aiming for his friend, diverting it just enough that it missed.
"Are you almost done yet?!" cried out the man, as the beast he fought hopped back, its landing sending a quake through the ground they probably felt all the way back in the village.
"Not yet, this is the most complicated Seal ever cast, and it must be perfect," said the yellow haired man, as he made seal after seal with his hands, the signs of jutsu he was casting appearing in the air about him as he kept going.
"That pervert you call a master would be faster than this!" shouted the man, as he charged forward, unable to hear the response of his friend through the roar of fury that came from the Kyubi no Kitsune. The man roared right back, curling his body into a ball in the air, and beginning to spin. Out of the spin came pouring black chakra, which formed a shield of nearly impenetrable power.
The kyubi's jaws locked on that shield, the teeth digging into it, but finding no way to pierce it, the monster shook its head, tossing the man aside, who uncurled and drew his hands back. Instantly, shining white chakra came from his finger tips, the stuff forming into long blades that shone like moonlight in the sky as he bounced off a tree, and dove for the surprised tailed beast, who roared out in pain and anger as the bladed dug home.
The thing was chakra given form and flesh, but the blades were of the same make. While smaller, and only a drop in the ocean of power that flowed from within the beast, the blades still hurt it in a way few mortal techniques could, driving the thing to take to the sky, jumping so a mountain was between them, even as the man leapt backwards himself, landing and then vanishing into a red blur that stopped beside Minato atop Gamabunta's head.
"How much longer?" he said, his voice barely a whisper as his breath came in ragged gasps.
"A minute more, but I need him to be still for a moment. Can you hold him?" asked Minato, and Hiro looked at him, before staring across the valley at the Kyubi, who's red eyes now shone like furious suns.
"It will be the end of me, but then, we both knew this was our last battle," responded Hiro, and Minato could do nothing but nod at him. Idly, Hiro wished they hadn't been so brash. The pair of them, some of the strongest in the village, him with the Four Gods Blood Limit, and Minato with all his skills, earned through hours of study, had ordered everyone else back. No one else needed to meet their end today, though he doubted many who had thought they would save the village knew this would be the two's final battle.
"Then I shall see you on the other side. Let us hope our wives forgive us for entrusting our children to Sarutobi," said Minato, finishing up one last seal, causing a noise like the ringing of a great bell to echo around them. That noise was then counterpointed by a howl of pure killing intent, as the kyubi charged over the mountain towards them.
"Til we meet again," Hiro told him, and then breathed in deeply, gathering the last of his chakra to him, exhausting even the energy that kept his heart beating as he did so, but giving him enough strength for one last assault.
"Dance of the Four Gods!" he cried out as he shot forward, chakra of red, black, white, and blue bursting from every part of his body, his clothing, battle armor thick enough to turn a blade, tearing itself apart from the inside, as the man dove towards his enemy.
"Speed of the Phoenix!" he shouted, and the instant his foot touched the ground, the red chakra flared, and he was gone into a blur.
"Armor of the Tortoise!" he added, curling into a ball again, a shield of black chakra surrounding him once more. This time he slammed home hard, smashing into the monster's face, causing even it to break a tooth as the force of the impact drove it back, and the man rolled over his snout, and onto his back.
"Claws of the Tiger!" he screamed, his body telling him it was over, but his will forcing it forward, as blades of chakra leapt out of his hands, which he held at his side, his fingers pointed downwards, so the technique dug into the kyubi's back, gouging a line into it, before the man hopped from it's back, landing behind it, and forcing it to turn around to face him, putting Minato at the monster's back.
"Roar of the Dragon!" he said finally, his voice nearly giving out on him as he brought his hands to his face, and blew. A gale of wind that shredded trees came from him, and smashed into the kyubi. That thing's flesh did not yield to the wind, but even it felt the stuff ripping at its form, the distraction serving its purpose, as a great hand of chakra grabbed the kyubi from behind, surprising it, as it was dragged into the form of Minato, the seal locking it within him.
Then the pair died. Either both at once, or one and then the other, it mattered little. The pair fell, their bodies pushed beyond their limit. In Konoha, a cheer rang up, celebrating the safety of the people, even as the shinobi looked dour and grim. They would find the bodies of the pair a few minutes after they fell, to be taken back to the village and buried with all honors, heroes to their people. Few even acknowledge in the lead up to the funerals, two young boys being sent to the orphanage, two boys who's names were changed so that none would suspect their heritage, at least, for a time.