In role playing games, railroading is when the players are forced into a specific set of actions regardless of their wishes. This chapter of the adventure path does this in the worst way possible. The plot goes as follows: The big bad has used an evil book to perform a ritual to enter the realm of Hastur, an evil demigod who looks like some guy in a yellow hood. The players must save the day and prove their heroism by....reclaiming the aforementioned evil book and performing the same evil ritual to enter the evil demigod's home realm. Sigh. The book is located in yet another ruined city filled with monsters who sit around waiting to be attacked. Seriously, is it possible to go half a block without stumbling into a ruined city in gaming? In the course of the adventure, the players will be forced to kill no less than two angels who are simply doing their jobs. (Three if you count that guru-angel turned emo). The book explicitly states that it is impossible to avoid killing the angels, without making a deal with a devil and even that only reduces the death toll to one. Not exactly friendly to players who play paladins and clerics.
Making matters worse is the fact that there is no real reason to do any of the adventure. No reason is given for why the players cannot simply use common dimensional travel magic to reach their goal. For that matter, what exactly is the threat that bad guy possesses? The text indicates that he may elevate his patron from demigod to outer god, but it never stated how this to take place and what its significance is. Hastur is already featured as a challenge rating 29 entry in the Beastiary 4 and seems to have no difficulty interacting with the mortal world.
The rest of the book is given over to discussing the evil book, but honestly, Paizo has already gone over similar ground in earlier projects and much more competently. Also, there is an overview of the Great Old One Xamen-Dor, but it is just another evil demigod who uses fungus to create undead. This setting already has about a half dozen bad guys who do the same thing and honestly, it is kitchen mold. How scary can it be? The villain has some other gimmick about becoming more powerful the more people know of it, but this never really plays much a role.
I cannot recall the last time, Paizo has published a turkey like this. Hopefully, it will be the last time this happens
