Dor Lazban, also known as the Abyss, is the prison Zhē Drūmor was cast into after his defeat in the First War. It was made by Hesphek somewhere deep beneath the earth, in a location known only to him.
The Paternic name Dor Lazban translates literally as “Black Pit”, from dor (“black”) and lazban (“mine, quarry, pit”).