Ala of Bulgaria: Monsters of the World
The Ala is a demon from Bulgarian mythology. It is described in folklore in various ways: wind-like, indistinct, human-like, raven-like, dragon-like, etc. It even has shapeshifting powers, in case any of the aforementioned don’t suit its mood. Or her mood, because she’s female. She also has the power to possess humans, and has a penchant for destroying crops, vineyards, orchards (my guess is anything that can photosynthesize) through extremely bad weather.
She is a danger to humans as well, and can cause ailments, even death. However, if you gain her trust, she makes a strong ally and will shower you with riches. Her nemesis is the dragon.
Map of the world courtesy of BYU Geography Department.