This list of mythical creatures that begin with this letter and I am constantly gathering information from each continent, and is continually being updated.
Bennu (Egyptian)
According to Egyptian mythology, Bennu was a self-created being said to have played a role in the creation of the world. He was said to be the ba (personality component of the soul) of the sun deity Ra, and to have enabled the creative actions of Atum. He was said to have flown over the waters of Nun that existed before creation, landing on a rock and issuing a call that determined the nature of creation.
He was also a symbol of rebirth and, therefore, was associated with Osiris. The Pyramid Texts, which date to the Old Kingdom, refer to the 'bnw' as a symbol of Atum, and it may have been the original form of Bennu. In this word the shape of a bird used is definitely not that of a heron, but a small singing bird.