Plesiosaurus

A species of dragon which has existed since ancient times. It is extremely large, and when viewed from afar looks like a mountain moving on its own. The dragon is a herbivore and quite gentle, but the moment it senses danger, it raises its spikes along its neck and back, and shakes them as a means of intimidation. The tail is very powerful, and can destroy a wooden structure to smithereens with a single blow.