There's a bizarre urban legend from Japan about a spirit known as Kuchisake-onna, (Slit-Mouth Woman). I find it goofy... ... yet unnerving. I'm very thankful I didn't hear this tale when I was a kid.
In life she was beautiful, until her jealous husband slashed her mouth from ear to ear. Her ghost wears a surgical mask. On foggy nights she comes up to children and asks "Do you think I'm pretty?" When the kid says "Yes," the mask comes off, the victim screams, and the chase is on! She comes after kids with a scythe (or knife), either killing them or carving them up to look like her.
That's one hardcore legendary creature! She makes the Boogyman look like a leprechaun. I bet she'd put the chupacabra on a leash and take him for walks. If she met Bigfoot, she'd make a fur coat out of him. She'd turn the Loch Ness Monster into clam chowder, and spread nasty rumors about La Llorona.