Incarnations, astral projections, and other similar constructions weren't that rare. Many powerful existences of other Planes were limited by the Mortal Plane's natural laws and, unable to use their true bodies to enter the Mortal Plane, could only send their incarnations or projections.
From a certain standpoint, such dimensional natural laws were a way of protecting the world of Eich.
As long as the Elemental Tide's density remained insufficient, the very existence of top-level existences in the Mortal Plane could distort this world's natural laws, causing unpredictable influences upon an area or even the entire plane.
