Natural Gates

Agrophon is especially close-knit with other planes, especially the Shadowfell and the Feywild. In a scarce few places throughout the continent, natural gates link Agrophon to these planes. Each gate takes the form of a surface, possibly a curved one. The smallest gate is the size of a doorway, and the largest encompasses an entire lake. When a person or object passes through the surface, they instantly find themselves on the other plane.
Some natural gates are permanent, and they tend to come in two sorts. "Purple gates" link to a parallel spot in the Shadowfell, while "green gates" link to the Feywild. From the other side, they're called "black gates" and lead back to the Material Plane. Other gates are temporary, and may link to more exotic destinations. In particular, portals to the Abyss tend to flicker about in Ossifrey, and are sometimes called "red gates."
These gates can be destroyed by carefully destroying any sign of its boundary. After a few days, its power dissolves and it no longer functions. However, a permanent gate cannot be permanently destroyed: a ghost of the surface still remains, and the portal reopens one week after the boundary is rebuilt. Only a 9th level spell can alter one of these gates for good.

Manifestation

The existence of a gate tends to shape the surrounding geography, physics, or flora. They don't have to be circular, but they usually appear as conspicuous closed loops. They could be marked by unnatural air pressure, streams of light apparently coming from nothing, or patches of alien plants.

Localization

There are permanent gates scattered throughout Agrophon; the known ones are marked on the map. Temporary gates may be created by a natural disaster, divine influence, or other such events.

Type

Metaphysical, Arcane