He is not exceptionally brave, strong, or in any other way marked out for unusual status as Hercules is. Iphicles is a perfectly normal human being.

Hercules has a twin brother who is actually his half-brother. Alcmene conceived Hercules by Zeus, thinking that he was her husband, and she conceived Hercules’ twin, Iphicles, the next night by Amphitryon. Eventually, they figured out that it must have been a god that had visited Alcmene the day before. The next day, the real Amphitryon returned, and there was a rather surprising scene in which Amphitryon couldn’t understand why Alcmene was not happier and more surprised to see him, and Alcmene couldn’t understand why Amphitryon insisted that he hadn’t been home for ages.

Alcmene went to bed with Zeus, thinking that her husband was home unexpectedly from the war. Remember, a god can appear in any guise he chooses. Amphitryon was away at war, and Zeus appeared to Alcmene disguised as Amphitryon. Hercules is conceived when Zeus tricks Alcmene into thinking that he is her husband, Amphitryon. Now, like many heroes, Hercules has a conception and a baby-hood that are fraught with difficulties or, at least, with unusual elements.