Vah Medoh is a mechanical construct in The Legend of Zelda: Breath of the Wild. It is one of the four Divine Beasts. Vah Medoh is made from Ancient Sheikah technology and takes the form of a giant eagle in the Tabantha Frontier region. Ganon sent Windblight Ganon to corrupt it, transforming it into one of the main dungeons. Link must defeat this boss to free Vah Medoh.
One hundred years before the events of Breath of the Wild, Rhoam Bosphoramus Hyrule, his daughter, her Knight Link, along with four other Champions sought to seal Ganon through the use of the Divine Beasts and Guardians. Ganon retaliated by taking control of Vah Medoh and the other Divine Beasts, turning them against the people of Hyrule. Revali, the Rito Champion who was in charge of controlling Vah Medoh, met his demise by Windblight Ganon, who then assumed control of Vah Medoh for the next one hundred years.
Once Link frees Vah Medoh from Windblight Ganon's control, it will fire a laser towards Hyrule Castle, weakening Ganon.
The name for Vah Medoh, like all four of the Divine Beasts, is based on a sage from a past installment of the Legend of Zelda series. Vah Medoh's name is a reference to the name of the sage of earth, Medli, from The Legend of Zelda: The Wind Waker. Vah Medoh is the only Divine Beast not to have a name in reference of a sage from The Legend of Zelda: Ocarina of Time.