Which character did Heracles save on his way to face Diomedes?

Heracles is known for his many adventures and heroic deeds, one of which involved him saving Alcestis. Alcestis was the wife of Admetus, and her story revolves around her selfless willingness to die in place of her husband. In one of the tales, when Heracles arrives at the house of Admetus and learns of Alcestis's sacrifice, he offers to confront Death itself to save her. This act of bravery and compassion is a hallmark of Heracles' character as a hero.

In contrast, the other characters listed—Andromeda, Penelope, and Hippolyta—each have their own myths and stories, but they are not directly related to Heracles' journey to confront Diomedes. Andromeda is famously known for her rescue by Perseus, Penelope is recognized as Odysseus's loyal wife during his long absence, and Hippolyta is associated with Theseus and the Amazonian legends. Therefore, the significance of Heracles rescuing Alcestis aligns with the themes of heroism and sacrifice that permeate his myths.