Jormag and the Mists
the things using portals are elementals and other magical creatures that retained their ability to use said portals after being corrupted, there aren’t any svanirs using them, at least not ones they themselves created. only thing jormag is a part of in all that is taking away the ability of the svanir shamans to go to the mists with their own power.
Fix what you have before you build something new