Mantle

Mantles, also known as planar borders and veils, are all that separates the planes colliding and wreaking havoc upon one another.
The mantles are not equal, the echo planes are thin and malleable, the Elemental planes are stronger but natural breaches can form, and the Weave bypasses all to suffuse them with magic. The mantle between the lower planes - the Nine Hells and Abyss, are much stronger, fiends are blocked from travelling to the Prime Material Plane without assistance from those on Runetalras. The Mantle between the Celestial Heavens and Prime Material Plane is whole other beast, in all of Runetalras’ known history no mortal has ever broken through it; even the deities that are presumed to dwell beyond the mantle have not breached it, but they have been known to be able to create the circumstance for celestial to pass through.
No Mantles are believed to exist to the transitory planes of existence such as the ethereal plane and the astral sea.
The Far Realms exist beyond the cosmic order and unfortunately for all life there appears to be no mantle that prevents access to Runetalras.

History

The strength of the mantles have ebbed and flowed just as like the tides. Throughout the known history of Runetalras this has been evident. During the Age of the Titans the elves are known to have emerged into Runetalras as they migrated from the Feywild into the Prime Material Plane.
The most significant example of the mantles’ ebb and flow is the Age of Blood, where they were thinned to the point that threats from across the planes almost destroyed Runetalras.

Type

Metaphysical, Astral