Gather close to learn a harrowing secret of the hidden world of Pathfinder Roleplaying Game development! One plan was to include occult monsters—psychic vampires, duergar, and advanced aboleths, among others—in the Pathfinder RPG Occult Adventures hardcover. During that book's development, however, we discovered that we wanted to explore more occult themes than would fit in a single book, and thus Pathfinder Campaign Setting: Occult Bestiary was born. Containing all the creatures originally intended for the pages of Occult Adventures as well as dozens more, Occult Bestiary provides GMs with nearly 50 new monsters with which to populate any occult-themed campaign, many of which use the new rules presented in Occult Adventures.
The monsters in the book can be easily broken into three categories. The first of these is the monsters that were going to appear in Occult Adventures—reimaginings of monsters that would have used psychic magic rules when they first appeared, had we had such rules at the time. These include aboleths, neothelids, seugathi, intellect devourers, and so forth. When they were going to appear in a hardcover rulebook, that seemed like a fine way to do it. But in a book set in the Pathfinder campaign setting, we needed to distinguish between a "normal" aboleth and a "psychic" aboleth. So instead of making an alternate aboleth, we created a new, CR 18 aberration in the same family: the omnipath.
The second type of monster in the book are those that come from real-world occult beliefs. Many of these are templates like the prana ghost (think Obi-Wan Kenobi in Empire and Jedi), the alter ego, and the psychic lich (whose phylactery is held safely within a mindscape). Others are standalone creatures like the boggart or the tattoo guardian. These were even more fun to concept than the first type of monster!
Finally, we have my favorite group: the monsters we just made up or that have existed in the Pathfinder campaign setting for years but that we never got to stat up. These include the potential familiar psyche serpent, the Lashunta's shotalashu mounts, new rakshasa and dark folk, and even Kalervo Oikarinen's RPG Superstar 2015 monster entry!
I always know a bestiary is ready when reading the entry for a random monster within inspires a new adventure that would let me use it; every monster in Occult Bestiary had me champing at the bit to throw it at unsuspecting PCs! What occult horrors are you most excited to subject upon your players?