im in the throne room and proffesior winthrop asked me to defeat the prince and that other guy that just walks around when i went back to him he told me to talk to him at the alter of the kings.when i went to him there he told me to go back to the throne room. then when i went back he wasn't there, he didn't say anything, and the arrow kept saying he was somewhere he wasn't. WHAT DO I DOOOOOOOOOOOOO!!!!!!