Nebel

"That’s where I need to go... Into the fog." "—Einsa" Nebel was the name given the fog that shrouds the entire Grauwelt. It was thickest where the Löwa resided.

The Nebel only began to appear after the deaths of Dietrich and the Great Hund  and was believed to have only grown denser with time. The origins of this strange fog were unclear.