Pathfinder Gamemastery Guide: Standard Hardcover - Rules of Play says:

Whether you are a new Game Master or experienced storyteller, you can always find new ways to hone your craft. This 256-page Pathfinder Second Edition rulebook contains a wealth of new information, tools, and rules systems to add to your game. Inside you will find handy advice for building your own adventures, designing towns, and creating vibrant characters alongside rules systems for dramatic chases, thrilling tournaments, and deadly duels. This book also includes more 40 pages of sample nonplayer characters, from the simple town guard to the vile cultist, presented to make your job as GM that much easier!