Paizo made such a strong initial showing with their first second edition core rule book you may think you do not need the Gamemastery Guide but the gamemastery guide is the collection of tools you will need to polish up your GM style and make your games even better.
Answer to title question: The basic benefit of adding the gamemastery guide to your Pathfinder 2e shelf is the collection of expanded explanations, specialized encounter tools, variant rules and worldbuilding tools.
We are going to look in depth at these features as well as:
- How good does it look and feel to own?
- How easy is the material to use?
- What sets this book apart from the Core Rule Book?
What is in the Gamemastery Guide?
Gamemastery Basics – This section of the book provides a short survey of tips and skills a game master may need starter information on. Sections dive deeper into subjects mechanically explained in the Core Rule Book but the Gamemastery Guide gives GMs base line expectations on use and flow. New and Novice GMs fill find this section the most useful and intermediate experienced GMs can use this section as reference. To most advance GMs the basics are well ingrained, but several readings of the basics can help advanced GMs understand what is under the surface of the Pathfinder Second Edition more quickly than going through games with trial and error.

Tools – Chapter 2 is what world builders and custom creature crafters have been waiting for. Player characters are built mechanically on a different method than everything else in the game world. The Gamemastery Guide provides the tools, tables and recommendations custom world builders have wanted since release. If you cracked open the Core Rule Book and thought the system was a little bit vanilla, this section is your flavor station. The tools section will give you the confidence to form your designs from the mechanical components into the fully fleshed out monster.
Subsystems – After you have completed building your new and wonderous world with the skills and tools from the first 2 chapters, the subsystem section provides rules for switching up modes of game play. Do you want to encourage your wizards to prepare more than just damaging spells? Use an exploration subsystem to reward them for creatively using their spells and reading the whole descriptions. Does your bard need a chance to show off their awesome skill selection and show the party sometimes words win over brawn? The influence system has you covered. Did you want to have a rules set for creating a crazy chase across the town that is more than simple fortitude checks? This is your section. Intermediate and advanced GMs will love to steal from this section. World builders can use these subsystems as seeds for their encounters. New and Novice GMs can grow into this section as they gain experience and confidence.

Variant Rules – Do you remember mechanics from other games you think might be great to plug into pathfinder second edition but are not sure where to start? Maybe you just can not jive with the ability score system from the core rule book? The Gamemastery guide provides a host of variant rules that can quickly integrate into the system as well as tips to keep numbers balanced. You have rules for rolling stats, or you can rip the level bonus out of proficiency. This section reads much like parts from the playtest which were great mechanics but did not sit well with broad audiences when combined with the rest of the system. The section is not comprehensive of all of the available variant rules across the table top community but a selection of tested options from the Paizo team.
NPC Gallery – Chapter 5 stays true to its namesake and gives a robust catalog of NPCs with stat blocks, images and unique abilities. Some game masters will have little use for this section as their players may not even think of attacking and forcing an NPC into combat. For everyone who has had the joy of wrangling a party full of kill happy murderers, this section will help you quickly defend the town from the players. The deeper use of this section is to show the diversity of skills, experience and lethality spread across non-adventurers in the world. Then GMs can take these roles and sprinkle them across their worlds as they see fit.
How Does this book look and feel?
The Gamemastery Guide comes in a standard graphic cover edition as well as the red and gold special edition. Both look great on the shelf and keep cohesive formatting with the earlier releases. When you open the book you know it is a second edition book quickly and it is durable enough to make continued transitions in your bag or backpack. Clocking in at 255 pages the book is much lighter than the core rule book or the Bestiary.

Can I find what I need in this Guide Quickly?
Navigating through this book, readers will have to make use of the table of contents and the combined Glossary and Index. Page numbers are linked to references and are included across the material. Each page uses a chapter legend on the top right boarder to help readers thumb through the book once they have sections memorized. GMs may need to copy the various tables in the tool section for rapid reference outside of the book when custom crafting monsters and hazards. There is no table index which will slow down some of the world builders when they have questions.
What is the Gamemastery Guide’s Special Sauce?

If the Bestiary and Core Rule Book are the entrees for the second edition system, the Gamemastery Guide is the underlying cookware used to produce the system. By learning and understanding the core ideas of the GMG you gain a fundamental control of the game.
Where players may disconnect from this book is in its deviation other tabletop role playing game structures. The Core Rule Book and the Bestiary are the minimal requirements for players and gamemasters. What was not included in that material were the build methods and variations expected to work best with in the system. These began being introduced in adventures and monthly released toolkits until the Gamemastery Guide was released. The only reasons for a player character to look in this book are for variant rules.
Thus the promise of the gamemastery guide is that it requires no context outside of the core rule books. Players have little need for the GMG and Game masters will want the GMG to improve their skills and learn new techniques. The secret sauce of the Gamemastery guide is that it remains a book players have no need to buy but Gamemasters need for reference and fully custom world building.
What I find Useful at My Table
The first three chapters of the Gamemastery Guide are crucial for being a GM in this system in my opinion. The premises of the core rule book are expanded in the first chapter while the needs of the worldbuilders and third party publishers are laid out in the second chapter. Subsystems look like simple and fun adds to games. Hexploration is common in the adventure paths our table runs and I am studying the influence and leadership subsystems.
Of the variant rules I find the level zero and deep background variants the most interesting. If your table is very used to 5th edition Dungeons and Dragons the proficiency with out level variant may help your table transition quickly into Pathfinder.
For our table the NPC gallery is more of a novelty. I am blessed with players who like to interact with NPCs socially and less by combat. That requires more descriptive notes that the NPC gallery does not provide.
If you are primarily a player and not a gamemaster there is little need to buy this book beyond a sense of completion. Your GM would let you know of any variant rules or subsystems they want to use and everything else does not modify player characters. Game masters are highly recommended to grab a copy of this book and keep it handy. World builders and creature creators will need this book as a reference.
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