The Shadowfell is a dark and eerie parallel plane in the Dungeons & Dragons universe. It is often associated with death, despair, and shadowy creatures. This realm reflects the material world but is twisted and bleak, filled with shadows and haunting landscapes. It serves as a home to various undead beings and is a place where lost souls may wander. Travelers to the Shadowfell may encounter locations like the City of Umbral, a ghostly settlement, or the Raven Queen, a powerful deity linked to death and fate. The plane is often used as a backdrop for adventures involving mystery, horror, and the supernatural.