Which is the best paraphrase of the paragraph? because he was dipped in the river styx, achilles was thought to be immortal. unfortunately his mother held him by the heel, and he was weak in that area. an “achilles’ heel” is a weakness that can lead to downfall. “achilles’ heel” is a term used to describe a weak spot. the phrase comes from the story of a greek soldier who was thought to be unbeatable—but was actually vulnerable. today the phrase “achilles’ heel” refers to a weakness that can lead to downfall. this refers to the story of a powerful greek warrior who had been submerged in the river styx during childhood. the article says, “achilles, a powerful greek warrior, was thought to be immortal because he had been submerged in the river styx during infancy.” it explains the meaning of “achilles’ heel.”