Forcecages

An innovative application of magic barriers developed early this century by Empire researchers, forcecages are binding boxes of energy that can trap an entity and prevent it from interacting with the world outside in any way.

Forcecages are virtually impregnable while they last, but they can be broken through if the trapped entity is strong enough. They can sometimes be dispelled by Piercing Crystals and by esoteric applications of certain magical spells, such as Mass Curing cast by a capable priest.