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A Bubble Beat's body is round, blue-grey, and limbless, with the Heartless emblem adorning its chest. It neck is black and its head sports two glowing, yellow eyes. It also has two short, blue-white horns on either side of its head, and a black and cyan pattern decorating its head that resembles headphones. A large, twisted, blue-grey horn sprouts out of the back of its head. Its most prominent feature is the large, cyan trumpet in the center of its face.
"Bubble" refers to the Heartless's manipulation of water. "Beat" references musical beats, which, in turn, is a nod to the Bubble Beat’s trumpet.
As with all Heartless of his species, it can use healing magic to heal its comrades. Its attacks are water-based, meaning they can damage-drain their opponents.