Bone Dragon

Bone Dragons are large dinosaur skeletons of Yoshis that you encounter underground. They spit fire and can somtimes be found in groups of three. Their weakspot is found on their head, meaning you want to jump on top of them to defeat them.

Bone Dragons resemble skeletons of the monster from Greek Mythology known as the hydra, a monster with multiple heads. In fact, on the beta version of Yoshi's Story, Bone Dragons weren't bones at all, but a full-fledged purple hydra.