Valley of Seers

The Valley of Seers is a stage in. It contains the Scenarios "The Sorceress of the Valley", "Shining Beacon", and "March of the Demon King", the fourth, thirteenth, and fifteenth Scenarios in Legend Mode. In the Master Quest DLC pack, it contains the Scenario "Darkness Falls", the fifth and final Scenario in Cia's Tale.

The Sorceress of the Valley
After learning that it was Cia who opened the Gate of Souls and used it to summon monsters and invade Hyrule, Lana joins Link, Impa, and Sheik and accompanies them with the rest of the Hyrulean Forces to the Valley of Seers, where they seek to close the gate and thus stop the tide of monsters pouring out from it.

With Cia waiting atop the Ruins Summit and summoning more Dark Forces to attack the Hyrulean soldiers, Sheik suggests that they capture the West and East Keeps to provide a foothold against the Enemy Base. However, Volga soon appears and engages in combat against Impa and her soldiers, delivering powerful attacks against the Hyrulean Forces. After Lana aids Impa in defeating Volga, he flees from the battlefield and allows the Hyrulean Forces to capture the two vital keeps. This leaves a path to the entrance to the ruins, but the allies find that it is being blocked by vines and the only way to get into the ruins is by lowering the bridge in the east side. It is then that an Engineer offers to assist them and begins to head out to it from the Allied Base while the Hyrulean Forces protect him from the advancing Dark Forces trying to stop him.

Once the Engineer safely reaches the East Ruins and lowers the bridge, Cia sends Summoners to the battlefield to thwart the Hyrulean Force's advance. Furthermore, the allies discover that there are vines impeding the path to the summit of the ruins, thus Lana searches the Western Room for an item capable of cutting them down. Conquering the temple reveals a Treasure Chest containing the Boomerang, which Lana, Link, Impa, and Sheik use to enter the Ruins Summit and confront Cia once and for all.

At the summit, the dark sorceress continues to summon monsters from within the Gate of Souls but stops when she realizes that her Triforce of Power is resonating due to Link and Sheik arriving at the scene. Sensing the presence of two pieces of Triforce, she summons Manhandla from within the Gate of Souls. Although the giant monster begins to attack the Allied Base, it is quickly defeated by the Hyrulean Forces. Back at the altar of the ruins, as the Hyrulean allies are readying to close the Gate of Souls, Cia summons a dark circle and engulfs the allies from below, stealing Link and Sheik's Triforce pieces. With the Triforce complete, Cia opens three Gate of Souls from across three different timelines and frees the fragments of an evil spirit within her, empowering the dark sorceress even more and leaving only one fragment left to free: the one guarded by the Master Sword.

Due to Cia opening the Gate of Souls through the ages, three portals from different appeared in the present day Hyrule. The young heroes, left with no other option but to split up and handle all three gates simultaneously, each depart to a different era, all charged with the task of closing their gate and returning safely from their quest.

Shining Beacon
When Link visits the valley for the second time, he finds Cia using all of her strength to power up Volga. After defeating Cia, she passes the Triforce of Power down to Lana.

After the Scenario finishes, Ganondorf becomes a playable character and his weapon, the Swords of Despair, becomes available for use.

March of the Demon King
The third visit follows the events from the Gerudo Desert. Ganondorf arrives to the valley, along with his servants Zant and Ghirahim, seeking to obtain the Triforce of Power which resides with Lana. While attempting to reach Lana, Impa enters the mission and tries to intervene. Upon being defeated, she splits herself into four other copies. Fighting the other copies however proves to be fruitless for Ganondorf's army as they respawn. Zant then suggests they should continue to pursue Lana, which would make the real Impa reveal herself and rush to Lana's location to defend her. While Ganondorf pursues her, the real Impa reveals herself and is fought. After she is defeated, she hints towards a plan that suggests Lana will be able to escape. Immediately afterwards, she leaves the mission.

Ganondorf then continues onward to the top of the Valley of Seers, eventually confronting Lana. Upon defeating her, she will suddenly warps away and relocates to the Fairy Fountain Keep. Impa then instructs her to use one of the Magic Circles she had set up during the confrontation with Ganondorf to escape the battle. To further increase her chances of survival, Lana splits herself into two copies as both attempt to reach different Magic Circles. Ganondorf and his forces charge after her, and defeat them both. He obtains the Triforce of Power, and sets out to Hyrule Field to claim the other remaining pieces of the Triforce.