Cycnus

In Greek mythology, Cycnus (Ancient Greek: Κύκνος means "swan") or Cygnus, was a bloodthirsty and cruel man who dwelt either in Pagasae, Thessaly or by the river Echedorus in Macedonia. Family Cycnus was the son of Ares by Pelopia or Pyrene. He married Themistonoe, daughter of King Ceyx of Trachis. Mythology Cycnus killed all of his guests until he was slain by Heracles. According to Pausanias, one of the men murdered by him was Lycus of Thrace. Pseudo-Apollodorus wrote of Cycnus the Thessalian, the son of Pelopia, and Cycnus the Macedonian, the son of Pyrene, as two distinct encounters of Heracles, mentioning them separately. The Thessalian Cycnus, he relates, challenged Heracles to single combat and was killed by him; the same is recounted by Diodorus. The Macedonian Cycnus, according to the Bibliotheca, also challenged Heracles to single combat; Ares attempted to avenge his son's death, but a thunderbolt was hurled by Zeus between the combatants, causing them to part.