BOOK SERIES
The Adversary Cycle
7 main books
The Adversary Cycle is a series of seven novels written by American author F. Paul Wilson. It was originally known as The Nightworld Cycle. John Clute, commenting on F. Paul Wilson's work in The Encyclopedia of Science Fiction, made several references to "the Adversary." Wilson, liking this, renamed the cycle.
Parent series: The Secret History of the World