Xone of Contention is the twenty-third book of the Xanth series by Piers Anthony.
Swell Foop is the twenty-fifth book of the Xanth series by Piers Anthony.
God of Tarot is a book published in 1979 that was written by Piers Anthony.
Cluster is the 1st book of the Cluster Series published in 1977 that was written by Piers Anthony.