Iphicles was the son of Alcmene and her human husband Amphitryon, whereas Heracles was her son by Zeus. He also had a sister, Laonome who married Euphemus or Polyphemus. Iphicles was the father of Heracles' charioteer Iolaus by his first wife, Automedusa, daughter of Alcathous. Afterwards, he fathered two children by Pyrrha, the younger daughter of Creon.
Iphicles was one night younger than his half-brother Heracles, who strangled the snakes which had been sent by Hera or by Amphitryon, and at which Iphicles was frightened. Iphicles, like his famous brother, grew into a strong man but could not match him in terms of strength. When Heracles was made insane once again by Hera, the hero threw into the fire his brother's two offspring by Pyrrha, who perished as a result.
Nevertheless, Iphicles went with Heracles on a punitive expedition against Troy, because King Laomedon refused to give Heracles the mares he had promised him before. Arriving in Troy, Iphicles and Telamon were sent by Heracles to the city to claim the mares, but they were thrown into prison by Laomedon. But Priam, the son of the king, disagreed with the decision of his father, sent two swords to the two heroes, and revealed the plans that Laomedon had for Heracles. As soon as Iphicles and Telamon heard this they killed their guards with the swords and returned to Heracles for the plans of Laomedon to be revealed. Then Heracles and his men went to the king and eventually slew him.
When Heracles ended his twelve labours, King Eurystheus accused him of killing him from the throne, and ordered that he, together with Alcmene and Iphicles, leave Tiryns. This is how Iphicles ended up in Arcadia where he joined Heracles on a punitive expedition against the Hippocoon of Sparta. In the ensuing battle, Iphicles was killed and Heracles was inconsolable over the death of his half-brother, and voluntarily went into exile to another city.
In some accounts, Iphicles fought in the first battle of Heracles against the Eleans and Augeas, and was wounded by the Molionides of Elis. In a fainting condition, Iphicles was carried by his relatives to Pheneus, home of his grandmother Laonome, where he was carefully nursed by Buphagus, a citizen of Pheneus, and by his wife Promne. They buried him when he died of his wound and was honoured with a heroum.
- Pseudo-Apollodorus, Bibliotheca 1.8.2
- Pseudo-Apollodorus, Bibliotheca 2.4.11
- Pyrrha was unnamed in Pseudo-Apollodorus, Bibliotheca 2.4.11 but was only hinted as the younger daughter of Creon
- Unknown writer, Megara 41-55
- Pseudo-Apollodorus, Bibliotheca 2.4.8
- Pseudo-Apollodorus, Bibliotheca 2.7.3
- Pausanias, Graeciae Descriptio 8.14.9
- Pausanias, Description of Greece with an English Translation by W.H.S. Jones, Litt.D., and H.A. Ormerod, M.A., in 4 Volumes. Cambridge, MA, Harvard University Press; London, William Heinemann Ltd. 1918. Online version at the Perseus Digital Library
- Pausanias, Graeciae Descriptio. 3 vols. Leipzig, Teubner. 1903. Greek text available at the Perseus Digital Library.
- Pseudo-Apollodorus, The Library with an English Translation by Sir James George Frazer, F.B.A., F.R.S. in 2 Volumes, Cambridge, MA, Harvard University Press; London, William Heinemann Ltd. 1921. Online version at the Perseus Digital Library. Greek text available from the same website.