A Thunderbird is a very large bird that can create lightning. They can also however shrink themselves down to the size of a regular bird.
According to "Hilda's Book of Beasts and Spirits", Thunderbirds spend their lives flying across the Earth, gathering knowledge and bringing back storm clouds. They are mostly solitary, but congregate in order to share the wisdom they gathered. They are however also prone to memory problems, resulting in the knowledge being forgotten or passed on incorrectly.
As of now, only a single specimen of the species is known to exist, being The Great Raven. In both "Hilda and the Bird Parade" and "Chapter 3: The Bird Parade" , he does refer to himself as A thunderbird instead of the, implying there may be more. If there are, they haven't been shown yet.
- The Great Raven (only currently known specimen)
- This fictional species of bird is based off the mythological creature of the same name.