The Biblical Underworld is a concept found in the Bible, referring to the realm of the dead. It is composed of four distinct regions: Styx (4 letters), Sheol (5 letters), Hel (3 letters), and HADES (5 letters). Styx is a river that separates the world of the living from the world of the dead. Sheol is the abode of the dead, where all souls go after death. Hel is the realm of the dead ruled by the goddess Hel. HADES is the Greek name for the underworld, ruled by the god HADES.