Elemental Gates and Vergences

The various planes of the world are usually depicted with the elemental realms surrounding Aiaos and its parallels - the Primal Wild and the Grim Plain. In reality, all of the planes overlap and interpenetrate one another, separated by the misty interstice of the Ether. Passage between these layers is possible via the openings at the cardinal extremes of the dome, or via planar magic of various kinds.
There are also places where the Aether is thin, and unshaped basal energy leaks through to the material plane, or where the fae can cross into Aiaos or mortals become lost in Wild or Wold. These places are called vergences - when the breach allows only energy through - or gates - if material forms can cross between planes. They are held to be sacred or deeply profane by druids, depending on whether they are tainted by the Void.
Vergences and gates are recognised by the same signs: etheric mists, elemental imbalance - excess of heat, damp, cold winds or earth tremors - and intrusions by elementals, fae or shadow creatures, depending on what plane the gate or vergence opens to. On the other side of the barrier, similar mists wreathe areas of elemental imbalance, and sometimes cases of material terrain.
Gates and vergences are sites of power for primal - or necrotic - magic, but there is a trade off between the power they can grant and the risk of attracting attention from the other side. They are especially favourable sins for powerful conjuration.