Hypnos Hypnos In Greek mythology, Hypnos (; , "sleep") is the personification of sleep; the Roman equivalent is known as Somnus. In the Greek mythology, Hypnos is the son of Nyx ("The Night") and Erebus ("The Darkness"). His brother is Thanatos ("Death"). Both siblings live in the underworld ("Hades") or in Erebus, another valley of the Greek underworld. According to rumors, Hypnos lived in a big cave, which the river Lethe ("Forgetfulness") comes from and where night and day meet. His bed is made of ebony, on the entrance of the cave grow a number of poppies and other hypnotic plants.
Pluto (mythology) . Jupiter got the sky, Neptune got the sea, and Pluto got the shaft." In Riordan's explanation, Hades "was more of a death god," but acquired his identity as a god of wealth among the Romans, along with a new name. Scientific terms derived from the name of Pluto include: Pluto (mythology) Pluto (Latin: "Plūtō"; , "") was the ruler of the underworld in classical mythology. The earlier name for the god was Hades, which became more common as the name of the underworld itself. In ancient Greek religion and mythology, Pluto represents a more positive concept of the god