Bone Dragon

Bone Dragons are large dinosaur skeletons 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 and ground pound to defeat them. Another way to defeat them is to hit them a couple times with eggs.

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.