Conduit

kwint's picture

Astral conduits are long silvery tubes that tether the Outer Planes to the Material+Plane. They are the "tunnels of light" that souls journey through on the way to and from the afterlife. They channel belief and prayer to the gods, and channel miracles to divine spellcasters. Without them, the gods could not exist in the Outer Planes; some claim the Outer Planes themselves couldn't exist without astral conduits channeling the belief of the Material Plane. At least one world, Athas, has no astral conduits at all, and consequently it has no gods.

Conduits are invisible from the Material Plane, but on the Astral they look just like the silver cords that astrally projecting spellcasters manifest, except much bigger. Perhaps the Outer Planes are somehow the soul of the Material Plane, projecting itself into the Astral Plane. In the Outer Planes, they sometimes resemble pits, wells, mouths, doorways, pearly gates, and other appropriate shapes.

Astral conduits, as important as they are, are guarded by spirit creatures of mysterious origin. Often they resemble grim reapers or other archetypal forms, but their purpose is only to protect the tunnels of light. They care nothing for the souls who journey past them.

Planar conduits[/b] are similar to astral conduits, but instead of touching the Material Plane they connect one outer planar Layer to another. This is generally how petitioners reach lower layers of the planes, though other travelers can use them as well.

Sources: 
A Guide to the Astral Plane
Planewalker's Handbook
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