I have now got all four tomes, and I have burnt the Heart. I want to return to town to become a zenmaster and valkyrie, but I can't exit the pyramid. I get stopped at the big doors, and am told that Cet's curse will keep me here for eternity. I can't even cast Call of home. Please don't tell me I had to leave before talking to Kerah.

If u have touch the portal of Isis and Kerah have been mind-control by Cet, u can not leave the pyramind until u kill Cet.