Well, yes this board is called "off topic" but that doesn't mean you should post a random and partially incorrect synapses of a part of the Illiad in threads about someone wanting their parents to let them buy video games.
You're completely right, and you complete your quest you should go scream sense into the hundreds of others who go off-topic once a couple weeks.
Achilles wans't immortal. He dies in the end of The Iliad
Yeah, I know he wasn't completely invincible, I just wasn't thinking at the time. Arrow in the heel and all that.