Ethereal Curtain

Description
Shimmering curtains connect the Ethereal Plane to the various Inner and Outer Planes. Just like portals (or color pools), ethereal curtains create conduits through the Astral Plane. They can only be entered through the Ethereal Plane, though a certain spells or rituals can find them from the Material Plane.

Ethereal curtains function like the color pools of the Astral Plane, but a traveler always becomes solid when entering the other side. Travelers stranded on the Ethereal Plane can use such a curtain to escape. Curtains can lead to demiplanes, though this is rare. Such demiplanes are often prisons, however.

In general, ethereal curtains are one way (1 in 10 chance of being two-way).