The title of The Chantry Guild (1988) fooled people. Sandra Miesel, in her afterward to The Final Encyclopedia, assumed it would be a sequel to Necromancer, and I, before purchasing it from the SFBC when it first came out, assumed the same. In fact, it's a direct sequel to The Final Encyclopedia (the first direct sequel in the Cycle, though not the last).
It begins with Amanda Morgan living on Kultis (one of the Exotic worlds), which is now occupied by the Others. Since the Exotics no longer had the Dorsai to do their fighting for them, they were easily defeated by the Others, and are now overseen by a garrison force of third-rate troops. Amanda acts as a sort of one-woman guerrilla force that rescues prisoners and in other ways make the occupation more bearable, to remind the Exotics that the Dorsai are still with them in spirit.
Hal Mayne is still at the Encyclopedia, searching for a way to access the Creative Universe, the place where all possible things live as Platonic ideals. Dickson implies that all human creation comes from there, and that creativity in humans comes from the ability of the unconscious mind to access it. It's what Donal used to become first Paul Formain and then Hal, and it's also where Walter Blunt found the powers he called the Alternate Laws. What Hal is searching for is a way to use it consciously as a weapon to defeat the Others. As the story begins, he's been searching for over a year with no success, and is close to giving up. The worst of this is that Tam Olyn, who's well over a hundred years old, is barely hanging on to life, and is desperate for Hal to make some breakthrough before he dies, much as Mark Torre was desperate to find a successor before he died.
Amanda comes to the Encyclopedia with news for Hal. A group of Exotics on Kultis has resurrected the old Chantry Guild. They live on a mountain, hidden from the occupation forces, and they spend their day marching in a circle, chanting the mantra The transient and the eternal are the same Amanda suggests that joining them could lead to new insights. Hal agrees, and they travel there. On his first turn in the circle, Hal has a vision of John Hawkwood, the 14th-century mercenary, spiritual ancestor of the Dorsai. (Had Dickson written the historical novels which were to begin the Childe Cycle, one would have been about Hawkwood.) On a later one, he has a vision of his great-great-grandfather Cletus, and realizes that Cletus (who had been a painter before turning to the military) used the Creative Universe to help him write his books on strategy and tactics
Next comes a long section in which Hal leads a group of Exotics to rescue a young girl, the niece of one of the Chantry Guild members. The murder of her parents has driven her mad, and she's become feral, living in the woods below their mountain. The Guild learns that she's been captured by the occupying army. Even though Exotics, having no military training, make fairly useless recruits, Hal is successful in the rescue. On the way back, he has an insight about the Creative Universe: not how to access it just yet, but that he's now ready to address the problem.
Once they're back, the Guild has an unexpected visitor: Bleys Ahrens. Bleys wants to discuss a truce with Hal. He begins with some vague threats about what the sacking of Earth would be like, and then makes his offer: drop Earth's shield and accept some immigrants from the Younger Worlds, and Bleys will call off the invasion. Hal sees through it quickly enough: these immigrants would be a fifth column, to divide Earth and weaken its resolve. Also, this would be a first step towards depopulating all of the Younger Worlds and leaving only an Earth no longer interested in space travel. Hal refuses the offer and returns to the Encyclopedia.
Once there, he orders a device built which will propel him into the Creative Universe, and it works: once there, he meets many people from his past: Hal's tutors, Donal's parents, his uncles James and Kensie, and his brother Mor, who forgives him. Hal sees his goal as a dark tower (in fact, the tower of the poem "Childe Roland to the Dark Tower Came"). He realizes that the Others are his creation: without Paul Formain's encouragement for the different facets of humanity to split off and form their own societies, the piece of humanity that feared growth would never have manifested itself as the Others. Hal also realizes that reaching the tower by himself is useless; he needs at least one companion for the Creative Universe to be part of humanity's shared reality rather than his own private dream. He brings the dying Tam, who sees his own dead: Kensie, Jamethon, and his brother-in-law Dave, all of whom greet Tam happily. (The men whose death Tam was responsible for form another three.) Hal leaves then, and goes back to the real world, where Tam, reconciled at last, peacefully passes away.
This is another long book; not the size of The Final Encyclopedia, but still twice the length of the earlier novels, and as the above summary shows, not all that much happens. Fully a third of it is the rescue sequence, which, while containing most of the book's action, seems disconnected and somewhat irrelevant. The parts of the book that are thematically important, Hal's quest to reach the Creative Universe, are largely expressed through visions and symbols: in that sense, The Chantry Guild is similar to Necromancer
Walter Blunt's place in the Cycle is complex. On the one hand, his call to pure destruction is wrong; Paul Formain was right to amend it to a call for creation in different directions. And the worship of destruction is what warped Tam Olyn's uncle and almost ruined Tam himself. On the other hand, Blunt was right that the technological nightmare Earth had become needed to end; his Chantry Guild became the Exotics, who became the champions of human advancement; and the Chantry Guild of this book originated in the assumption that Blunt had insights that the Exotics had lost. Last, Blunt's Alternate Laws form the basis for Hal Mayne's idea of the Creative Universe. Blunt was in some ways a Moses who, for his sins, was never granted the Promised Land. Or to say it another way, he was Thomas Paine: the right man to help start the revolution, but not someone you'd want to help organize the result.
At this point, with Hal in possession of what he needs to defeat Bleys Ahrens, the conclusion of the Cycle is in sight. We even know what that book would have been called: Childe. For whatever reason, Dickson didn't write it. Instead, he decided to tell us the story of the rise of Others from the point of view of their leader, in the books Young Bleys, Other, and finally the posthumous Antagonist