This list of mythical creatures that begin with this letter and I am constantly gathering information from each continent, and is continually being updated.
Daidarabotchi (Japanese)
Daidarabotchi was agiant in Japanese mythology, sometimes said to pose as a mountain range when sleeping. The size of a Daidarabotchi was so great that his footprints were said to have created innumerable lakes and ponds. In one legend, a Daidarabotchi weighed Mount Fuji and Mount Tsukuba to see which was heavier, but he accidentally split Tsukuba's peak after he was finished with it.
The Hitachi no Kuni Fudoki, also told of a Daidarabotchi living on a hill west of a post office of Hiratsu Ogushi who fed on giant clams from the beach, piling the shells on top of a hill. In the larger Ibaraki Prefecture, Daidarabotchi was considered a benevolent giant, moving mountains to aid the people of Ibaraki.