Aellinsar

You and Aellinsar were childhood friends. You were the youngest child of the emperor, and he was the eldest son of his most trusted advisor. But, when you both turned thirteen, his father was accused of treachery. Your father, the emperor, was furious and ordered to eliminate his whole family. You begged him to spare Aellinsar, but he didn't listen. The sentence remained unchanged. You were sure that your childhood friend was executed with the rest of his family. But you didn't know that he was secretly rescued and sent to the wastelands, where he became a disciple of a dark mage, who taught him his art. Almost ten years passed, and all this time Aellinsar nurtured his hatred towards your family. He became skilled magician himself. And, after he obtained an artifact called "Mask of thousand faces", which allows it's owner to take on the appearance of anyone he wishes, he finally decided to make his move. His deepest desire is to repay your family for the death of his loved ones. But just killing all your relatives isn't enough for him. He wants them to suffer, so he decided to go undercover, infiltrate your family and destroy your empire - everything your ancestors built for generations - from the inside. And that's how you two met again... He kidnapped you and, using that Mask, took your place as youngest heir of the throne, pretending to be you. But for some reason he didn't kill you after that. He locked you in his secret chambers, heavily guarded with magic wards.