> Not only do people in ancient stories not switch sides in fights but Achilles, say, would never win because his army was composed of the rejects from the Troj

> Not only do people in ancient stories not switch sides in fights but Achilles, say, would never win because his army was composed of the rejects from the Trojans’. It's not in the Iliad, but in the Aeneid one of the Greeks pretends to desert in order to sell the story of the Trojan horse, and the Trojans do kindly accept him. https://en.wikipedia.org/wiki/Sinon https://en.wikipedia.org/wiki/Sinon (However, it turns out that that he was still really loyal to the Greeks and the Trojans made a mistake by believing him.)