Note: Dopplegangar is used throughout the story as Dark Link's name. This word is German, literally translated to: "Double Walker" A fitting name I thought. Enjoy.
Birth of Shadow
In the very beginning, there was Link. A hero that was born simply to defend, to protect and to serve his majesty. In the end there was Dark Link, an abyssal clone of Link, a villain that was born to kill, hurt, and to destroy those that were in the way to his path to power.
No one really knew where Dark Link was created, it was speculated that he was created by Ganon during the seven years of Links Slumber in the sacred realm. It was also speculated that he was created in a bordering kingdom as a ploy to infiltrate and ruin the reputation of Link, by causing trouble under the guise of the hero. Neither of these theories are correct. In fact the truth is one that is known only by a select few,even Link wasn't aware that he was the cause of Dark Link..
Dark Link was created unintentionally by Link himself. When Link set the third spiritual stone upon the altar, and grabbed the master sword, he was cleansed from all the evil that he had held in his heart. However this evil was only recycled, not destroyed. Merely weakened, the shadow waited until he could grow enough in strength to challenge his creator. To fulfill his only objective. Destroy Link.
Born into agonizing pain, the only way that this pain could subside would be if his creator was destroyed, as long as he would survive, all the evil that Link would think of, all the bad things that were purged from the Hero, went into the foul creation of the villain. The only way to kill a minion fed by source of power, would be to cut off this source. One could not live if the other was alive.
A hundred years ago
Clang. Clang. CRASH. An ongoing battle went on between two swordsman, unmatched by none other than each other. A battle of epic proportions, that would lead only to one outcome: Certain death. CRASH. A pot went flying towards Links head, only to miss at the very end, by a sharp dodge by the hero. CLANG. Link avoided the pot, only to be lead into a fight of epic swordplay, Link however had the disadvantage, as he was still barely recovering from his near miss from the pot. Sure it had missed, but the dodge had cost something that was vital to winning a sword fight: Balance. One thing was for sure: Dopplegangar knew how to keep Link on his feet.
Link just barely dodged a jab towards his shoulders, it was time to get offensive. Swinging to the left, Dark Link parried his attack with ease. He sent a flurry of swings each wild and in no way predictable. It was stupid and very unprofessional of him, but he had to see. Once again with ease Dark Link blocked the attacks and then countered each and every one. The amazement was easily seen on Link's face. Never had he been bested like this.
He wasn't going to do this so soon. He had never really even had the intention of using them. Reaching into his pocket he grabbed a small crystal. The crystal was translucent, and you could see the orange center. Dins Fire. A crystal enchanted by Din herself at the creation of Hyrule, and all else. Put into the protection of one of the Great Fairies, the guardians of Hyrule. This would have to help Link in his final moment.
The moment would have to be now. Dopplegangar jumped towards Link, Link had the sacrifice ready: A fist full of blood. He waited. Waited as the Shadow came near him, he wanted him to taste the element of Din. As the shadow started to descend upon Link, Link threw down the crystal, a sphere of fire appeared, and grew in volume until it imprisoned the shadow. Howls of agony pierced through Links head, and when he was sure that the shadow was dead, he released the spell. Nothing was left to be seen. Only ashes, to signify that something had once opposed Link.