Nurikabe
The Nurikabe takes the form of a wall, usually invisible, that blocks the
path of travelers as they're walking. Some iterations of the legend say
that trying to go around the wall is futile as it extends forever. Others
say that knocking on the bottom left part of the wall with a stick will
make it disappear, but that knocking on the upper part of it will yield no
result. It has been suggested that the legend of the Nurikabe was created
to explain travelers losing their bearings on long journeys.
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Karakasa Kozō or Kasa Obake
These silly looking yōkai are transformations of Chinese-style oiled-paper
umbrellas. They have a single large eye, a long, protruding tongue, and
either one or two legs upon which they hop around wildly. Karakasa kozō
are not particularly fearsome as far as yōkai go. Their favorite method of
surprising humans is to sneak up on them and deliver a large, oily lick
with their enormous tongues—which may be traumatic even though it isn't
dangerous.
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Hyakki Yagyō
The Hyakki Yagyō is the dreaded night parade of one hundred demons—an
event when all of the yōkai, oni, ghosts, and other supernatural creatures
leave their homes and parade through the streets of Japan in one massive
spectacle of utter pandemonium. Humans foolish enough to go outside on
these nights, or curious enough to peek out of their windows in hopes of
catching a glimpse of the supernatural, are either killed or spirited away
by the monsters.
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