|Spoiler Alert! This article describes a subject that is sensitive to plot development.|
The Decline Timeline is one of the three timelines occurring after Ocarina of Time. This timeline was confirmed by Nintendo upon the release of Hyrule Historia. This timeline is somewhat of an "alternate reality" of the Adult Timeline. In the Decline Timeline, Link fails to defeat Ganon at the end of Ocarina of Time, resulting in Ganon taking over Hyrule. The games in this timeline, in order of chronology, are: A Link to the Past, Oracle of Seasons, Oracle of Ages, Link's Awakening, The Legend of Zelda, and lastly The Adventure of Link.
The Imprisoning War
After many greedy Hylians went to the Sacred Realm in search of the Triforce, they were transformed into monsters in Ganon's army. Eventually, the army attacked Hyrule and the Seven Sages were commanded to seal the Sacred Realm once again and the soldier fighting bought them enough time to seal them away though at a high cost.
The Era of Light and Dark
This era contains the events of A Link to the Past, Oracle of Ages, Oracle of Seasons, and Link's Awakening.
After a series of disasters, the King of Hyrule offered a reward to one who could stop them. Agahnim stepped forward and stopped them using amazing magic. The King made him a chief advisor and a priest, however, Agahnim brainwashed all of the soldiers and sent six maidens to the Dark World. In order to prove worthy to become a hero, Link journeys to find the three Pendants of Virtue. The Pendant of Courage, Wisdom, and Power. Once he finds all three, Link is capable of wielding the Master Sword. Once he retrieves the Master Sword, Link confronts Agahnim, but during the battle, Link is pulled into the Dark World. Link must now rescue the seven Maidens, including Zelda. who was sent to the Dark World by Agahnim. Link finally confronts Agahnim once again in Ganon's Tower, and is successful in destroying him, but it turns out that Agahnim was being controlled by Ganon all along. With the power of the Master Sword, Link defeats Ganon. The Triforce appears before the Hero, and he makes a wish upon the Triforce. He wishes for peace to return to the world, and the Triforce returns into the hands of the Royal Family, and the Dark World fades away.
The witches Twinrova plotted to revive Ganon, however, they needed the flames of despair, sorrow, and destruction lit along with a human sacrifice. To do this they sent Onox to Holodrum, and Veran to Labrynna. The Triforce told Link to go to the castle and upon touching it he was sent to Holodrum. In Holodrum, Link met the Oracle of Seasons, Din. Almost immediately thereafter, Din was kidnapped by the evil General Onox. Link travelled through Holodrum, aided by the Maku Tree and using the Rod of Seasons, and collected eight Essences of Nature to defeat Onox and save Din. Upon his return to Hyrule, a similar story unfolded where he was transported to the land of Labrynna. There he met Nayru, the Oracle of Ages, where she was kidnapped by Veran. Link saved her as well, using the Harp of Ages and with the help of a different Maku Tree. After defeating Onox and Veran, Link combatted Twinrova and won. Unfortunately, they sacrificed the last of their power to resurrect Ganon, who Link then promptly defeated. Bidding farewell to the people of Labrynna, Link set out to return to Hyrule.
On his way home to Hyrule, Link was shipwrecked on the island of Koholint. The only way he could make his way home was to awaken the Wind Fish using the Instruments of the Sirens, which he collected on Koholint. Shockingly, the island existed solely in the dreams of the Wind Fish. By waking him up, Link destroyed the small island. Afterwards, he set adrift, and what occurred to him afterwards is unknown.
The Golden Era
Ever since Ganon was defeated by the hands of The Hero, each generation of Hyrule's kings used the Triforce to preserve order in the land. One king who had used the power of the Triforce was worried that it would be put to misuse after his death. In avoid this, he hid the Triforce of Courage, placing a spell over the land of Hyrule. His magic made it so that a crest would appear upon a person deemed worthy enough to wield the Triforce of Courage. Though the Prince and Princess were heirs, the king had doubts about his son, and seeing more promise in his daughter, Zelda, passed the Triforce to her in secret.
When the king passes away, the Prince becomes king. But with no crest upon his hand, the power of the Triforce he inherited was not complete. The new king was advised by his confidant, a wizard, that Princess Zelda seemed to know what was behind these events. Despite being interrogated by her brother and the wizard, Zelda tells nothing. The wizard finally lost his temper and threatened to cast a spell that would make her sleep for all eternity, but Zelda still refused. The wizard cast the spell and Zelda collapsed where she had stood.
Regretting what he had done and taken by sadness, the young king placed Princess Zelda in an altar in the North Castle, hoping someday she would be revived. To make sure this tragedy would never be forgotten, a custom was established that made it so every girl born into Hyrule's royal family would be named "Zelda." This story became the legend of the first Princess Zelda. The king reformed and continued to rule the land to the best of his ability, but the kingdom fell into decline.
No one appeared who was able to use the Triforce, and Hyrule continued to shrink. It continued until Hyrule was a single, small kingdom. Though the Triforce of Wisdom was handed down generation to the next, the memory of the Triforce of Courage and the Tragedy of Princess Zelda I was lost.
The Era of Decline
This era contains the events of The Legend of Zelda and Zelda II: The Adventure of Link.
Thousands of years later, a demon army led by the Demon King Ganon invaded Hyrule and stole the Triforce of Power. The current Princess Zelda divided the Triforce of Wisdom into eight pieces, hiding them in different places across the land. She ordered her nursemaid, Impa, to find one that could defeat Ganon. Ganon then captured Zelda and sent his minions after Impa.
Impa, after much traveling, finally found herself surrounded by Ganon's followers. Just then, a boy named Link appeared. He managed to outwit Ganon's underlings and rescued Impa. Impa explained the situation to Link, and he then made the decision to defeat Ganon and rescue Princess Zelda.
Link locates all eight dungeons and retrieves all shards of the Triforce of Wisdom. Using the power of the Triforce of Wisdom, Link is able to defeat Ganon and save Princess Zelda. Peace is brought back to the kingdom of Hyrule, but only for a short time.