The Aetheric Sargasso
The weird, horrific creatures of the Mythos are native inhabitants of the Aether. They are the wellspring of nightmare, know by the Sidhe as the Fomoiri and by Earthlings as the Great Old Ones (Cthulhu Mythos). They and their minions are deadly hazards to Aether travel.
High ranking members of the Unseelie Court are known to make “pets” of the smaller (frigate sized) creatures.