On spirits

Witches

brujas

Will-o'-the-wisp

Seen across multiple cultures all across the world.

The scientific explanation calls it chemiluminescence, caused by the organic decay of the swamps/bogs it occurs over.

On water spirits

Foxes

Kitsune, focus of Inari

Japan

Kami; elements of the landscape, forces of nature, manifestations of musubi (結び), the interconnecting energy of the universe.

In nature, everything is related to something.

An object that can potentially house a kami spirit is called a yorishiro. A yorishiro that is inhabitated by a kami is a shintai. In spite of what their name may suggest, shintai are not themselves part of kami, but rather just temporary repositories.