Ethereal Plane

The Ethereal plane existed adjacent to the Material Plane. The Ethereal touched the Material Plane at all points and the barrier between these realms was know as the Border Ethereal.
==== While in the Border Ethereal, a traveler could still see into the adjacent plane but only dimly and not very far, whereas those on the bordering plane could not see the traveler without magical detection. Verbal communication was not possible between the Border Ethereal and the bordered plane. The Ethereal was unique among the many planes in that an individual could exist in two planes simultaneously: the Border Ethereal and the adjacent plane. ====

==== When a traveler crossed into the Border Ethereal, she and all her possessions were converted to their Ethereal equivalents, metal became ethereal metal, flesh became ethereal flesh and so on, allowing free movement (in most cases) in any direction through the solid matter of the adjacent plane. Since everything was permeated with ethereality, an air-breathing creature could breathe ethereal air and could not drown in an ethereal lake nor be crushed by an ethereal rock. However, not all in the adjacent plane was insubstantial. ====

==== Living things larger than one-celled animals generated an aura that radiated around them and prevented passage to their interior, so an ethereal traveler could not place a weapon inside a living creature where it would materialize and cause damage. A jungle would be an extremely torturous maze to navigate; it would be much easier to float above the vegetation or pass below its roots. Dense metals such as lead or gold also prevented passage of ethereal matter. And finally, some magic spells and alchemical mixtures could form an effective barrier. ====

==== Travel in the Ethereal and Border Ethereal was accomplished by force of will—you wished to go somewhere and you did, at your normal rate of movement. There was a sense of up and down but no real gravity existed. Objects released from possession would hover where they were dropped; it was impossible to fall in the Ethereal plane. ====

==== The Deep Ethereal swirled with large blobs of protomatter which could form their own demiplane when a critical size was reached. Powerful wizards could also bend the proto-matter to their will and create a demiplane. These nascent planes might exhibit some of the characteristics of the Inner planes or the Prime, but with their own rules of gravity, material make-up, etc., and even support life. Most demiplanes eventually collapse into themselves and break up or merge with the Material Plane. ====