Nemesis

Nemesis, or Ramnousia, Rhamnusia, was the goddess or spirit of divine retribution against those who succumb to hubris. The Greeks personified vengeful fate as a remorseless goddess; the goddess of revenge.

Origins
Nemesis has been described as the daughter of Oceanus or Zeus, but according to Hesiod, she was a child of Erebus and Nyx. She has also been described as a daughter of Nyx alone. Her cult may have originated at Smyrna.

In some myths, Nemesis produced an egg from which hatched two sets of twins: Helen of Troy and Clytemnestra, and the Dioscuri, Castor and Pollux. While many myths indicate Zeus and Leda to be the parents of Helen of Troy, the author of the compilation of myths called Bibliotheke notes the possibility of Nemesis being the mother of Helen. Nemesis, to avoid Zeus, turns into a goose, but he turns into a swan and mates with her. Nemesis, in her bird form, lays an egg that is discovered in the marshes by a shepherd, who passes the egg to Leda. It is in this way that Leda comes to be the mother of Helen of Troy, as she kept hte egg in a chest until it hatched.

Acts and Deeds
Although a respected goddess, Nemesis had brought much sorrow to mortals such as Echo and Narcissus. Narcissus was a very beautiful and arrogant hunter from the territory of Thespiae and Boeotia, who disdained the ones who loved him. Nemesis lured him to a pool where he saw his own reflection in the water and fell in love with it, not realizing it was only an image. He was unable to leave the beauty of his reflection and he eventually died. Nemesis believed that no one should ever have too much good and she had always cursed those who were blessed with countless gifts.