In Greek lore, a type of Demon that assaults travelers and taunts them. Planos (singular) means “vagabond” or “deceiver.”
According to JOHN CASSIAN, a father of the church in the fourth century, most planoi are tricksters, but some attempt greater harm, including the incitement of bloodshed. In his work Conferences, Cassian described the planoi as
. . . so seductive and sportive that, when they have taken continual possession of certain places or roads, they delight themselves not indeed with tormenting the passers by whom they can deceive, but, contenting themselves merely with laughing at them and mocking them, try to tire them out rather than to injure them: while some spend the night merely by harmlessly taking possession of men, though others are such slaves to fury and ferocity that they are not simply content with hurting the bodies of those, of whom they have taken possession, by tearing them in a dreadful manner, but actually are eager to rush upon those who are passing by at a distance, and to attack them with most savage slaughter: like those described in the gospel, for fear of whom no man dared to pass by that way. And there is no doubt that these and such as these in their insatiable fury delight in wars and bloodshed.

Further Reading :

– Cassian, John. “Conference 7.” In The Conferences of John Cassian. Translated and notes by Edgar C. S. Gibson. Available online. URL:\#7.0. Downloaded February 3, 2008.

The Encyclopedia of Demons and Demonology – Written by Rosemary Ellen Guiley – Copyright © 2009 by Visionary Living, Inc.