Ethereal Medium

The ether is a proposed medium where light travels. It was disproved until discoveries regarding spirits exist or interact in a medium humans cannot sense or interact directly. Many supernatural experts referred to this "world" as the Ethereal Medium. Only specialized instruments and powers can harness, sense, or interact with this world.

Ethereal-bound creatures can interact with the physical world at fissures, specific days, events, or summoning. Most of the interesting (meaning popular with the masses) supernatural events are Ethereal phenomena. Since the Ethereal Medium is bound to the physical world, both these worlds weave each other to form supernatural phenomena.