I love the idea of this book, I wish this happened more often. They took what they saw wrong with their game and spent proper time and effort to come up with proper solutions. It's pretty rare for a company to spend this much effort on tweaking things. The new proposed mechanics for combat and skills are unique and great ideas to help customize your groups' gaming experience.
I hope they release more books like this in the future. I've love for more variations for multiclassing, and I'm still waiting for a summoner archetype that removes the class summon monster ability and focuses more on the eidolon.
Highly recommend it, especially for anyone interested in how someone goes about making a gaming system. It provides awesome insights.
Don't take it the wrong way. You can have tons of fun with this book in other games. I played a mesmerist and it was hilarious, had a whole Doctor Orpheus thing going on. The Kineticist can be flavored a little and it basically becomes a bender from Avatar! How freaking cool is that?!
There are quite a few spells and special abilities that feel like they can only come in handy in very specific ways though. All the mindscape things would almost never come up in a regular game. This feels very much like a book that would be a lot more fun if all your players HAD to take a class from this book, which is a terrible premise for a core book.
On a personal note, almost none of these classes work with Mythic Adventures...
No seriously. The vigilante class is freaking batman. Look at the art for chapter one and for the character. HE'S BATMAN. Of course they also have archetypes if you want to make Hulk, Sailor Moon, even He-Man. With the archetypes from other books the list goes on.
My favorite part, and I cannot wait to test this properly in a game, is the social combat. It works a lot like playing craps or roulette. You get a pool of Determination points which you use to place a bet then you roll off with your social skills check! Seriously it sounds like lots of fun!
So I bought the PDF of this now that it was finally available. Had a look through it. I always love having new ways to look at Pathfinder. The class archetypes seems interesting, I doubt I will use the sanity rules anytime soon.
The Corruption Rules on the other hand... I think i might be using those at some point.
Overall, is this book worth it? If you really love Pathfinder and Horror, hell yes it is.
Are you just a fan of Pathfinder? Possibly, it depends on if you absolutely need access to every book with tweaks that they release like me.
I say it's worth a peek.