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 linked to the Raven Queen, the goddess of death. Traveling to the Shadowfell can be dangerous, as it is a place where light struggles to penetrate. The plane is inhabited by creatures like shadows and wraiths, which thrive in its gloom. Adventurers may find themselves facing challenges related to fear and loss while navigating this unsettling environment.