The old hag was all smiles showing her toothless jaws. You may think that she was the weakest among them due to her hunched back but this hag had been buffed up until her punches can blast through concrete walls unhindered and furthermore, she will not be injured or feel uncomfortable. She was like the mercenary of the group. Both her and the teenager were lucky to have been spared by the system of the obligations by those torturous quests. The only quest that they have was the current one requiring them to survive this final battle.