John Clute, commenting on F. Paul Wilson's work in The Encyclopedia of Science Fiction, made several references to "the Adversary."
[citation needed] Wilson's website[1] suggests an order of The Keep, Reborn, The Touch, The Tomb, Reprisal, Signalz, and Nightworld.
it is only in Nightworld that they were retroactively made part of the Cycle, as their respective protagonists all come together to fight the final battle against the Otherness.
These seven books make up the "core" of "The Adversary Cycle", many more novels and short stories tie into the series.
These books take place in the last three years before Nightworld and include some of the main characters from the original Adversary Cycle.