[DanHoward]

Originally Achilles was just a skilled warrior whose main weakness was his pride. Later his weakness was his love for Polyxena. Ovid's Metamorphoses suggested that Achilles had a vulnerable spot somewhere on his body but it wasn't until Statius' Achilleid that he develops a vulnerable heel. It seems pretty pointless for Homer to spend hundreds of words describing Achilles' shield and armour if he was invulnerable to weapons and, as noted above, he was wounded in the elbow during one encounter.

If I was running this kind of game, I would set it before the Trojan War, and I would make the major characters NPCs. That way I wouldn't have to try and stat characters with plot protection and I wouldn't have players doing stupid things because they know they can't die. There are plenty of minor characters in the Iliad for the players to choose from to play and if they die, it doesn't upset three thousand years of tradition. The battle at Troy can be the big finale.