Achilles was dipped into the river Styx as a baby by his mother so he would be invincible. The only part of him not touched by the waters was his heel, where his mother was holding him, thus "Achilles Heel."
According to the ancient Greek mythology , his armor , shield and sword were forged by the god Hephaestus . Homer's "The Iliad" is the story of Achilles, but does not end with his death. According to Virgil, Achilles was slain in the ninth year of the war by an arrow that pierced his heel. The archer was either Paris, a Trojan hero, or the god Apollo, who was actively assisting the Trojans in this war. It was after Achilles' death and the ensuing drop in Greek morale that Odysseus devised the Trojan horse strategy, seeking a quick end to the war.