Even in the movie, Achilles was killed when Paris put that arrow through Achilles' achilles tendon....but, yeah...the movie was different...it was much different from the Iliad.
Paris shot Achilles several times. If Achilles were invulnerable, they would have bounced off of him. He died due to blood loss from the arrows he removed. The only one he DIDN'T remove was the one in his ankle.
It was the movie's way of explaining the myth. Making it reasonable. They find a dead Achilles (a person rumored to be immortal amongst some) with a single arrow sticking out of his ankle. Words get spread, and suddenly, Achilles' ankle is his only weak spot.
Anyways, apparently YOU didn't read the Iliad. Achilles actually ISN'T invulnerable in the Iliad - that part of the myth was created by other stories. Achilles is actually wounded at one point, and spurts blood.
No, I read it...Achilles doesn't even die in the Iliad...and I know he isn't invulnerable...it was prophesied that he would die...and never see his home again if he continued his war in Troy. Even in the Odyssey...Odysseus speaks to Achilles while in Hades. So, Achilles was never meant to be invulnerable....only great. In the Iliad...a whole slew of warriors were the offspring of some god...and many of them died. Just because a warrior may be half god doesn't give them invulnerability or immortality....but, I do believe it amps their abilities to higher levels than just a normal man...even above Cap's.
No, they are considered gods...she is even called a goddess in the Iliad...and she has access to Olympus. She just doesn't have the cult worship that the major gods have. I'm not saying that a mortal can't defeat a demigod...I'm just saying that demigods would and should have power above an average human with two human parents. In that sense...I believe Achilles would have an advantage over Cap...I'm not saying that Achilles would definetely defeat Cap...I just believe that in an all out fight...the Achilles of myth and legend seems out of Cap's league. Achilles in the movie looks pretty good...hell, he took out Nathan Jones in the beginning..lol. But, I do get your point....and I agree...humans have outwitted godlike characters before. I just believe that without and PIS....anyone with godlike blood should be able to best any human on a regular basis.