Castle Roogna1979
by Piers Anthony
Millie, a ghost for 800 years wants only one man--Jonathan, and he's a zombie. To prove himself, Magician Dor volunteers to get the potion that can restore Jonathan to full life. But he has to go back through time to do it, to a peril-haunted, ancient Xanth, where danger lurks at every turn....From the Paperback edition.
— from OpenLibrary
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