They arise out of folklore, the “things that go bump in the night,” as the Scotts used to pray, according to the University of Pittsburgh. The Atlantic quotes Michael Dylan Foster, a Japanese folklore scholar at Indiana University Bloomington, who believes some of the creature tales are sort of immigrants, with origins in Chinese legends and from various Buddhist texts.

And there are oh! So many creatures in the yokai pantheon. The Japan Times reports a book titled Yokai Attack! which is a sort of catalog and survival guide. You know — just in case. There listed are any manner of creepy thingies arising from someone’s fertile imagination: the “vicious karasu-tengu, a shape-shifting bird; odokuro, a giant, stalking skeleton; and” — a personal favorite — “akaname, a feral, red-skinned consumer of mildew and dead skin.” (Kind of a multi-purpose loofah? Scrub you, then the shower?)

There are plenty from which to choose, as Japan Talk makes clear. The kappa are river monsters, maybe based on giant salamanders (like that isn’t terrifying enough?). Tsukumogami are another form (so to speak) of shape-shifter — inanimate objects that, come their 100th birthday, not only animate, but become self-aware as well. Rokurokubi look as ordinary as we do during the day, but come nightfall their necks get long — really long. Also, their heads detach and float around. So maybe that thing last night wasn’t really a bat. Maybe it was — naw.