Rock Chuchu

Rock Chuchus (or Rock ChuChus ) are a type of red Chuchu that wears a stone mask over its head for protection. The weight of the rock prevents them from jumping at Link, however.

The Legend of Zelda: The Minish Cap
In The Legend of Zelda: The Minish Cap, Rock Chuchus wear brown, horned rocks, and appear wandering around Mount Crenel and Veil Falls. Normal sword attacks will not work against their armor, but certain advanced ones such as the Rock Breaker will. They can be quickly defeated with bombs.

The Legend of Zelda: Phantom Hourglass
In The Legend of Zelda: Phantom Hourglass, Rock ChuChus now have smooth, gray rocks, and hide inside large rocks that resemble the throwable rocks. When Link approaches, the rock vibrates before bursting, with the Rock ChuChu emerging. From here, they act the same as previously, though their masks can be destroyed with the grappling hook, and the hammer also defeats them instantly. They first appear in the Temple of Wind, reappearing on Goron Island, the Goron Temple, and Dee Ess Island. A single one also appears in the Temple of Ice.