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The Sword of the Vale (Japanese: 大地の剣 Sword of the Earth) is an anime-exclusive location in the Unova region. It is one of the settings of the first Best Wishes series movie, White—Victini and Zekrom and Black—Victini and Reshiram.
Inside the Sword of the Vale
One thousand years prior to the events of the films, the Sword of the Vale was at the center of the Kingdom of the Vale, with the King of the People of the Vale residing in it with Victini. However, when the king's sons, the Heroes of Truth and Ideals, began fighting over their beliefs, the Dragon Force flowing through the kingdom reversed, leading to the devastation of the land. To save his people, the king borrowed Victini's power and used it to enhance the strength of hundreds of Solosis and Duosion in the castle, lifting it into the sky with all of the village's people within. It flew from the vale to the top of the mountain where the Dragon Force's leading edge flowed before landing.
Eindoak Town developed on that same mountainside, into a prosperous and rich town. Despite this, Damon, a descendant of the People of the Vale, wished for the restoration of the Kingdom of the Vale, and ultimately discovered that he could accomplish that goal by reactivating the Sword of the Vale and flying it back to its original location. Once Ravine, Glacine, Mannes, Juanita and others supported him, he captured Victini using the castle's Pillars of Protection and lifted the castle skyward, allowing the Dragon Force to flow back to the ruined land and begin restoring it. However, shortly thereafter, the Dragon Force went out of control again, spreading devastation over the land once more.
The Sword of the Vale flying through the air
Once Damon discovered this, he asked Reshiram and Zekrom for help in using the castle to stop the chaotic Dragon Force, and they caused the Dragon Force to reverse on itself and move upward into the Sword of the Vale itself. Juanita, Carlita, Cilan and Iris escaped, but Damon insisted on staying until the crisis was solved, and Ash could not leave because the barrier generated by the Pillars of Protection sealed Victini inside. As the Dragon Force flowed through the castle, it began to fly out of control, first throwing Damon off and then rocketing into the atmosphere with Ash, Victini and Pikachu still aboard. Damon, after being rescued by Juanita's Golurk, used the shared power of Golurk, Reshiram and Zekrom to try to destroy the Pillars of Protection so the castle would descend, but they failed. Victini, however, was able to destroy the pillars using Searing Shot and then V-create.
Once the power of the Dragon Force was released from the castle into outer space, it began descending once more. Damon, with the help of Golurk, Reshiram and Zekrom, carefully guided it downward, following the Dragon Force until it reached a mountaintop near the ocean, where it landed. This suppressed the flow of the Dragon Force and stopped it from causing any further devastation. Now in a new location, the Sword of the Vale was last seen in the credits of the films, when Damon and his family began the task of rebuilding the Kingdom of the Vale.
The Sword of the Vale has several properties that are unique to it. Most notably is its ability to fly, through a combination of the psychic power of the many Solosis and Duosion in its lower chambers, Victini's strengthening those powers, and control provided alternately by the King of the People of the Vale or Damon's Sigilyph. Also involved with the control of the castle are eight "Pillars of Protection", magical structures that generate a barrier to seal Victini and its energy inside the castle. Using a pedestal that projects holograms of the Pillars of Protection, the pilot of the castle can use it to control the flow of the Dragon Force.