Baba Yaga

The Baba Yaga is known as Russia's most famous witch, but she looks more like a hag, really. She lives in a hut that stands on chicken legs, and at night kidnaps and eats children. Though most witches have the standard broom for their transportation, instead the Baba Yaga sits in a flying mortar, using the broom to sweep away her tracks.

The Wild Hunt

The Wild Hunt is a gathering of mysterious and fantastic huntsmen, usually made up of historical or legendary figures, usually led by someone even more infamous. A few notables include King Arthur, Herne the Hunter, and Odin. They bring their horses, hounds, equipment in search of very specific prey, though it varied from rare animals to wild maidens.

Three Wise Monkeys

The saying goes "see no evil, hear no evil, speak no evil."
Often depicted with monkeys, they are...

Mizaru, who covers it's eyes.
Kikazaru, who covers it's ears.
and Iwazaru, who covers it's mouth.

What's not commonly known is that there is sometimes a 4th monkey named Shizaru, embodying the saying "do no evil" and is shown crossing his arms, or... holding it's crotch, it looks like.