Megaera

Megaera is one of the three Fury Sisters. She is sent by Hades to stop Zagreus from escaping the Underworld. Zagreus must defeat her before progressing to Asphodel during any given escape attempt. After her first defeat, Megaera will join the House of Hades as a character that can be interacted with, though she will still attempt to stop Zagreus from entering Asphodel. She will be found drinking in the House's lounge, but only after a run in which she was defeated; if the lounge has yet to be re-opened, she will instead hang around in the hallway, on the opposite side of Zagreus's door from where Nyx usually stands. Apparently, she has been tasked with handling matters in Tartarus apart from her sisters; this includes dealing with Zagreus. According to Megaera, a war amongst the mortals has made the Underworld particularly busy, and her sisters are handling matters elsewhere.