Materia is the material world, the world of Vendrith that surrounds one unless one travels to other Planes. In the cosmological Great Flow theory, the plane of Materia is believed to (roughly) lie at the centre of the flow, as it is characterised by a balance between matter and nothingness, pressure and free flow, light and darkness. It is in this balance that the conditions which allow most people, animals and even monsters to exist. Creatures that don’t originate from Materia or otherwise are adapted to living in other planes are called Extraplanar Creatures.