Poseidon

According to Greek mythology, Poseidon was the god of the sea and the earthquakes, in the same pantheon with Eros and Hephaestus, (TV: Planet of Fire) as well as the son of the titan Kronos and the god of Atlantis, where a temple was dedicated to it. (TV: The Time Monster)

Romans adopted it in their pantheon under the name of Neptune. (PROSE: Byzantium!)

Besides Zeus, he was the only one with power equivalent to Hades. Hermes impersonated him long enough for Persephone to summon the real one. Poseidon then expelled Hades from Earth, sending him back to the Underworld. (PROSE: Deadly Reunion)

In some versions of the Medusa story, she wasn't always ugly. She was a beautiful nymph with golden hair. When Poseidon fell in love with Medusa, Athena became jealous and turned her into a Gorgon. (TV: Eye of the Gorgon)