Slaying of Cycnus (Kyknos) by Heracles, Black-Figure Corinithian? Amphora, 7th century BC, Munich
1. Cycnus (Kyknos), son of Ares and Pelopia or Pyrene. Cycnus was bloodthirsty and cruel man who resided in Macedonia. He aspired to building a temple to his father constructed from the bones of travelers, whom Cycnus would kill in passing. His building days came to an end however, when Cycnus encountered Heracles near the River Echedorus. Desiring to please his father, Cycnus challenged Heracles to single combat, wishing to add Heracles' bones to his temple. This was an extremely foolish move, as Cycnus should have recalled the numerous times in which Heracles bested his father in combat.
When Ares heard of Cycnus and Heracles' confrontation, he was furious, and rushed immediately to assist his son. However, he was stopped by Athena, who advised him to wait and hear what the Moirae, the Fates, had in store for Cycnus. The Fates told Ares and Athena that Cycnus would be slain by Heracles unless the hero was killed before then. These words, designed to halt Ares from going to help his son, in fact fueled his anger even more. Ares descended immediately to assist Cycnus, and went into battle with Heracles. Ares was just about to strike a hit at the hero, when Athena appeared, and blocked Ares' hit. Heracles took this opportunity to wound Ares in the thigh, causing Ares to retreat to Mount Olympus, leaving his son to his fate. Cycnus was indeed killed by Heracles as the Fates predicted, and his bone-built temple was never completed. (Apollodorus 2.114).
See also "Cholchos" Oinochoe 572/525 BC
Heracles fighting Cycnus , 500/490 BC
Other Men Named Cycnus:
2. Cycnus and Phaeton. This Cycnus was the son of Sthenelus and a good friend or lover of Phaeton. After Phaeton died, he dove repeatedly into the river Eridanos attempting to retrieve Phaeton's body. The gods turned him into a swan to relieve him of his pity.
3. Cycnus, king of Colonae in Troas was the son of Poseidon and a King of Colonae (in Troas). His second wife tricked him into trying to kill his son, Tenes. Tenes survived and both later supported the Trojans in the Trojan War. Achilles killed Cycnus and he was changed into a swan. (Ovid XII, 64)
4. Cycnus the swan. Son of Apollo, Cycnus was handsome but cruel and mean. Soon, he had only one friend that finally got fed up with Cycnus and killed him. Apollo turned him into a swan.