I could never see my character's black hair much.... After the quest "Rescue the Archaeologist" my hair is always white and i am always 55 or 65 years old. After that it's all white hair and creepy looking. I don't know if donating to the temple of Avo will get your black hair back. I think that will just change your age in the Hero Status, not your looks. I passed the other Archaeologist quest wher eyou have to enter the demon door to see him, so i can't hero save. So does hero save give back your looks after you donate and save?