For my entry, I present the grandmother of all fairytale witches, Baba Yaga.
A prominent figure in Slavic folklore, Baba Yaga is something of a complex character. She frequently portrayed as a wicked witch who sets up obstacles for young heroes and heroines like Vasilissa and has a penchant for eating babies and enslaving said heroes and heroines.
However, she is also seen as a benefactress, aiding those who either get the better of her or display a good measure common sense and politeness. The latter is pretty rare as it has been said that every time she is asked a question, she ages a year.
In stories and illustrations like that of Ivan Bilibin and Viktor Vasnetsov, her mode of travel is a giant flying mortar and pestle, while her house is a little windowless cabin atop a pair of giant chicken legs.
So beloved in her homeland and even beyond that thanks to the Russian Diaspora, Baba Yaga's appearances are not limited to literature. She has been portrayed in cartoons, graphic novels, television, and films; for example Morozko or, better known to MST3K fans, Jack Frost in which the dub renames her as "Hunchback Fairy".
Fun fact: Baba Yaga here was portrayed by Russian actor Georgy Millyar (1903-1993).
So here's to a totally wicked witch! May her mortar and pestle fly true!