The debate surrounding the Christian aspects of C.S. Lewis’s The Chronicles of Narnia, J.R.R. Tolkien’s The Lord of the Rings, Philip Pullman’s His Dark Materials and J.K. Rowling’s Harry Potter has revealed not only the prominence of religious themes in fantasy fiction, but also readers’ concerns over portrayals of religion in fantasy. Yet while analyses of these works fill many volumes, other fantasy series have received much less attention. This critical study explores the fantastic religions and religious themes in the works of American and Canadian writers Stephen R. Donaldson (Chronicles of Thomas Covenant), Guy Gavriel Kay (Fionavar Tapestry), Celia S. Friedman (Coldfire Trilogy), and Brandon Sanderson (Mistborn) series. References to biblical tradition and Christian teachings reveal these writers’ overall approach to Christianity and the relationship between Christianity and the fantasy genre.