This pdf is 31 pages long, 1 page front cover, 1 page blank inside of the front cover, 1 page editorial, 1 page ToC, 1 page advice on reading statblocks for novice DMs, 1 page SRD, 1 page advertisement and 1 page back cover, leaving 23 pages of content for the new cult.
This review depicting a cult contains SPOILERS, thus I'd advice potential players to skip to the conclusion.
Still here? All right! Havra Zhoul's cult is not a common "More-Evil-than-thou"-Cult, which becomes readily apparent even from the start - so-called dictums of the cult, i.e. sections from the writing of the holy book of the cult, depicting the philosophy of the sect.
An organized task-force created by a paladin who got too radical, the cult of Havra Zhoul takes the idea of the "good shepherd" and people as a flock and develop it to the logical extreme: A totalitarian organization that seeks to impose the dictums of the cult at any cost. Starting off as a seemingly benevolent secret police that punishes evil-doers the system can't seem to grab/defeat or who have powerful official backing, the cult could even work with the PCs, increasing the horror of realizing the lows to which the cult could sink.
Even better, the cult per se might actually improve the overall situation for a time...before imposing draconic rules, that is. Especially when used in noir-settings like in "Streets of Zobeck" or Freeport, the edge the cult gives law and order might make the organization the lauded heroes of the downtrodden and opens up whole revenues for adventuring - have e.g. the PCs guard murderers and similar criminals, perhaps because they're still needed...
Of course, adventure hooks galore are provided for the cult, beginning with a magic investigator (complete with stats) who lies low, for he knows that he's bitten off more than he can chew and will pay dearly for his discoveries. A sample safehouse of the cult and the artifact housing the founder's soul, the holy book of the cult is included as well as two sample rites to create two unique kinds of devils from willing and unwilling supplicants as well as 2 new templates that grants infernal powers to those fully initiated into the cult. We also get a new witch archetype centered on poison-usage and a new class of magic items, necklaces of venomous beads.
Additionally, we get the full 4 NPC-descriptions of the cult's leaders and powerplayers entangled in webs of deceit, each with at least 2 pages of information, hooks, mannerisms and CHARACTER. There are a lot of NPCs out there, but these are truly fully developed characters, going so far as making even a chaotic evil decadent bastard a valid potential choice for an ally of the PCs. The writing of the NPCs and the cult itself is, let me make this abundantly clear STELLAR. The excerpts from the Dictum make this pdf not only a joy to read, but also gives the DM a great bunch of philosophical things to paraphrase/read to his players when confronting them with the cult, gradually introducing them to ever more extreme appliances of the teachings.
editing and formatting are top-notch, I didn't notice any glitches. Layout adheres to the 2-column RSp-standard and the b/w-artworks are neat. The pdf comes fully bookmarked and features an extra pdf of collated stat-blocks as well as one optimized for use with e-readers. I LOVE this pdf. I really do.
Pierre van Rooden gives us not one run-of-the-mill cult, but a concisely-written organization that makes sense in every word and makes membership in the cult a believable goal, perhaps even for players. Depending on your campaign, the shades-of-grey approach taken herein might challenge a lot of overtly simplistic and boring dichotomies many players tend to take as for granted, making this pdf not only a good read, but offering an organization that very well could change how your PCs think about law, order and the price living in a peaceful society might entail. A sub-textual criticism of our ever-growing fear and mounting surveillance in real life is evident and, with divinations etc., an experienced DM could use this cult easily as a foundation for a roleplaying social commentary. Or you could simply use it as written and still enjoy one of the best NPC-organizations released for PFRPG to date. My final verdict? Not surprising at this point - 5 stars and the Endzeitgeist seal of approval.