Folktales from Ravka is a collection of novellas written by Leigh Bardugo. Those short stories are literally "folktales" from "Ravka", set in the Grishaverse, and can be seen as companion stories to The Grisha Trilogy.
The Witch of Duva
There was a time when the woods near Duva ate girls...or so the story goes. But it’s just possible that the danger may be a little bit closer to home.
The Too-Clever Fox
In Ravka, just because you avoid one trap, it doesn't mean you'll escape the next.
In this third Ravkan folk tale from Leigh Bardugo, a beautiful girl finds that what her father wants for her and what she wants for herself are two different things.