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Perhaps the most famous ushi-oni appears as a protective symbol in the Uwajima Ushi-oni Festival, which is held in late July in Uwajima of Ehime Prefecture. Something like the dragon dancers at a Chinese New Year celebration, this ushi-oni is represented with a huge, multiple-person costume with a cloth body and a carved, painted head held upon a pole. It has a sword for a tail, and is thought to drive away evil spirits.
Another well-known ushi-oni is a massive, brutal sea-monster which lives off the coast of Shimane Prefecture and other places in Western Japan and attacks fishermen. It is often depicted with a spider- or crab-like body. This ushi-oni seems to be connected to another monster called the nure-onna, who sometimes appears before an ushi-oni attack and tricks the victim into holding her child, which then becomes stuck to the person's hands and grows heavier in order to hinder escape.
Yet another ushi-oni is depicted as a statue on the grounds of the Negoroji temple in Takamatsu, Kagawa Prefecture. It is a bipedal monster with huge tusks, spurred wrists, and membranes like a flying squirrel. A sign nearby explains that this creature terrorized the area about four-hundred years ago, and was slain by a skilled archer by the name of Yamada Kurando Takakiyo (山田蔵人高清). He dedicated its horns to the temple, and they can still be seen to this day. 
In One Piece, Gyūki: Yuzume is the name of an attack Zoro uses to defeat T-Bone.
In both the Nurarihyon no Mago manga and anime series the beast known as Gyūki, happens to be an ushi-oni with the head of an ox and the torso of a spider-like creature with large claws that with its demonic powers would lead lost travelers astray and prey on them.
In Naruto, Gyūki is Killer Bee's tailed beast, a cross of an ox and an octopus. He can transform into the beast at will.