High Quality Content by WIKIPEDIA articles! Demons is a common name for many different creatures in the Shannara series of epic fantasy novels by Terry Brooks. The `true` demons were sealed long ago within an alternate universe, named the Forbidding; this prison is `maintained` by the Ellcrys, a sacred Elven tree; if she dies, the Forbidding fails. The Demons first threatened the Four Lands when the Ellcrys began to die in The Elfstones of Shannara, but were defeated by the united efforts of the Bordermen of Callahorn, the Elves, Trolls, Dwarves, Allanon, the Elfstones wielded by Wil Ohmsford and Amberle Elessedil. These same Demons played a central role the High Druid of Shannara trilogy, where they attempted to break free of their prison once more (see below).