Chain Chomps first appeared in Super Mario Bros. 3. Chain Chomps bear a resemblance to a ball and chain and are typified by their large, tooth-filled maws and incessant biting. Shigeru Miyamoto's inspiration for the Chain Chomps was from a childhood experience: a dog once ran up to him and tried to bite him, but the dog's chain held it back.
As a result, Chain Chomps also possess canine qualities, such as barking, and are commonly used as guard dogs throughout the Mario series. The presence of ancient statues of them in the Dry Dry Ruins suggests that they have been used as such for centuries. Many Chomps in the Mario series have been part of the Koopa Troop, though a couple of them have been shown to be independent. [Source: Mariowiki]
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