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Basics from the Core Rulebook

Source PRPG Core Rulebook pg. 396
It's one thing to play a character on an adventure. It’s quite another to run the adventure as a Game Master. It’s a lot more work, sure, but it can be a lot more rewarding to create an entire world for your friends to explore.

But what exactly is a Game Master?

Storyteller: First and foremost, the Game Master is a storyteller. He presents the world and its characters to the players of the game, and it is through the GM that the players interact with them. The Game Master must be able to craft stories and to translate them into a verbal medium.

Entertainer: A Game Master must also be a master at improvisation. He has to be ready to handle anything that his players want to do, to resolve situations and issue rulings quickly enough to keep the pace of the game going at an entertaining clip. A Game Master is on stage, and his players are his audience.

Judge: The Game Master must be the arbiter of everything that occurs in the game. All rule books, including this one, are his tools, but his word is the law. He must not antagonize the players or work to impede their ability to enjoy the game, yet neither should he favor them and coddle them. He should be impartial, fair, and consistent in his administration of the rules.

Inventor: The Game Master’s job does not end when the game session does. He must be an inventor as well. By creating NPCs, plots, magic items, spells, worlds, deities, monsters, and everything else, he propels his game’s evolution forward, constantly elevating his campaign into something greater.

Player: Just because he’s playing dozens of characters during the course of a session doesn’t make him any less a player than the others who sit at the table.

Starting a Campaign

Source PRPG Core Rulebook pg. 396
Before you run a game, you need to know what kind of game you’ll be running. Whether you write out the plans for the coming session in a dozen notebooks, scribble down ideas and key NPC stat blocks on a bunch of sticky notes or your computer, or just have a vague idea of a plot and a few names in your head, you’ll need to prepare parts of your adventure before the game begins. Some GMs enjoy the challenge of presenting a “sandbox” for the players to explore at their whim, but even then you need to know what kind of things are in that sandbox for the PCs to encounter. And as a general rule, everything you can prepare before the game begins will save you time making decisions during the game. Even more important, preparation beforehand allows you to maintain consistency—few things ruin the suspension of disbelief more for a group of discerning players than having the Game Master call the local innkeeper “Radimus” one session and “Penelope” the next. Preparing for your adventure beforehand can help you maintain innkeeper gender identities and so much more!

Of course, the backbone of any campaign is the adventures that comprise it, be they an intricately connected series of plots and storylines or an open-ended sandbox of possibility. But where do these adventures come from? There are, essentially, two sources for adventures. You can build your own from scratch, or you can run a published adventure. Both options have different pros and cons, and you certainly don’t have to limit yourself to only one choice for the duration of a campaign.

Published Adventures

Source PRPG Core Rulebook pg. 396
Published adventures are your friend. As a Game Master, you’re going to be spending a lot of time as it is preparing for games—and when you don’t have time to come up with an adventure, a published adventure can be a godsend. By studying how published adventures are put together, you can hone your own adventure-creating skills. And by running a published adventure for your group, you leave the details of invention and creation to the adventure writer, giving you time to focus on the game play itself.

The most important thing to remember when using a published adventure, though, is that the writer of the adventure doesn’t know your group the way you know your group. If you know your players are particularly paranoid and assume all helpful NPCs are out to get them, then a published adventure about a kindly cleric who’s actually a shapechanged demon probably won’t work well for your group. Feel free to change published adventures as you see fit, either while you’re reading them or during play. If, for example, one of your players has written into his character’s backstory that his father was killed by an orc warlord and he became an adventurer to someday get revenge on that orc, go ahead and change the hobgoblin warlord in the adventure into an orc. Adapting adventures to your group and your play style in this manner is an important part of running published adventures, since it customizes the experience to your group and makes it all the more enjoyable.

Paizo Publishing offers a large variety of published adventures in its Pathfinder Modules line and complete campaigns in the form of its monthly Pathfinder Adventure Path installments. To learn more about these valuable GM resources, please visit

Building an Adventure

Source PRPG Core Rulebook pg. 396
There are countless ways to build an adventure. The classic method is to simply write everything out beforehand. While this does get everything you need to know about the adventure down on paper, it’s an awful lot of work. If you’re the only person who’ll ever be running the adventure, it’s okay to simply outline the plot, draw a map of the adventure site, create encounters and stat blocks, and have at it. An adventure need not look like much more than a shopping list—you only really need to write down what you can’t easily remember come game time.

One important tip to remember about adventure writing—you’re not writing a story. The main characters of the adventure should be the players, and they’re missing from the tale when you prepare the adventure. Instead, think of the adventure as an outline for a script. You can have an idea in your head of how things will work out, but if you avoid making assumptions about what your characters will do in the adventure and instead just focus on creating the building blocks of the adventure (such as room descriptions, NPC motivations, stat blocks, and the like), you’ll be much more capable of reacting to the unexpected when the PCs do their thing.

Whatever you decide to do in your adventure, there are three elements that, if you prepare them beforehand, will save you a lot of time and anguish in the end—stat blocks, encounters, and treasure.

Preparing for the Game

Source PRPG Core Rulebook pg. 401
Your job as Game Master begins well before the game session does. Your most important duty before a game is, of course, to prepare for that game. This means reading up on the adventure you’ll be running (or perhaps even designing the adventure), preparing any props or handouts you might need to give the PCs, prepping the play area for guests, and so on. In the days leading up to the game, you should resolve any out-of-game issues that your players have—email is a great way to do this, since it creates its own written record you can use to add to your campaign journal (see page 403). This includes helping players level up their characters; answering questions they may have about using noncore rules and supplements for spells, feats, and the like; and providing them with answers to questions they have about the game world.

For example, say one of your PCs is searching for his missing sister, who was abducted years ago by a thieves’ guild. You can drop in clues about this sister in the game, but between games, the PC might want to spend a few days investigating a lead in the local underworld or at the City Hall of Records. Personal quests like these are a great way for a player to build his character’s history and personality, but they can get in the way of gaming when other players are at the table. If you can’t afford to spend one-on-one time with players, handling these side-quests via email is a great way to take care of the situation.

You should also ensure that all of the players can make the game, and if not all of them can, decide if the game should be canceled or not. There are few things more frustrating than realizing that half your group can’t play, especially if some of the players had to drive a long way to reach the game. If a player is absent, decide what happens to his PC. Can someone else play him? Does he gain experience and treasure as usual?

Make sure that accommodations are met. If your game session’s going to last a long time, think about where folks can go for lunch or dinner—if you’re planning on providing food, make sure it’s ready to go before the game begins. Many tables organize responsibilities among the players—if a GM hosts the game at his house, the players might split up the task of providing drinks, snacks, or meals. Try to use common sense here—while it’s tempting to load up with potato chips and soda pop, gaming is no excuse for poor health! Of course, if your home is not the hosting site for the game, that doesn’t let you off the hook. You as GM are the organizing force for the gathering—you’re technically throwing the party, and it’s your responsibility to see that your players have a comfortable, enjoyable place to game, otherwise the game itself will suffer.

During the Game

Source PRPG Core Rulebook pg. 402
The bulk of this book provides the rules you need to adjudicate the game and run things, but there are many other problems and events that can come up that require you to think quickly before they become disruptive. Listed here are several of the more common speed bumps and problems that you’ll invariably be called upon to handle during the game.

Cheating and Fudging: We all know that cheating is bad. But sometimes, as a GM, you might find yourself in a situation where cheating might improve the game. We prefer to call this “fudging” rather than cheating, and while you should try to avoid it when you can, you are the law in your world, and you shouldn’t feel bound by the dice. A GM should be impartial and fair, and in theory, that’s what random dice results help support. Some players have trouble putting trust in their GM, but dice offer something that’s irrefutable and truly non-partisan (as long as the dice aren’t doctored or loaded, of course). Still, it’s no good if a single roll of the dice would result in a premature end to your campaign, or a character’s death when they did everything right.

Likewise, don’t feel bound to the predetermined plot of an encounter or the rules as written. Feel free to adjust the results or interpret things creatively—especially in cases where you as the GM made a poor assumption to begin with. For example, you might design an encounter against a band of werewolves, only to realize too late that none of the PCs have silver weapons and therefore can’t hurt them. In this case, it’s okay to cheat and say that these werewolves are hurt by normal weapons, or to have the town guard (armed with silver arrows) show up at the last minute to save the PCs. As long as you can keep such developments to a minimum, these on-thespot adjustments can even enhance the game—so the town guard saved the PCs, but now that they have, it can give you leverage over the PCs to send them on their next quest as repayment to the guards!

Divine Intervention: The literary term for it is deus ex machina—“god from the machine.” This is what happens in a story when a plot device manifests in an unexpected (and usually unsatisfying) way to resolve a story element, typically in a way that renders the actions of the main characters meaningless. Even great authors use deus ex machina to resolve stories now and then, so don’t be afraid to use it in your game if things are looking grim. The town guard rushing in to save the PCs from the werewolves in the previous paragraph is an excellent example of deus ex machina, but so is the old classic of “divine intervention.” In this case, the PCs are faced with an impossible situation and you, as the GM, change the situation so that they can now achieve their goals, perhaps after a PC begs for aid from his deity.

You can quantify divine interventions, if you wish, at the start of a campaign. Tell every player that they get a fixed number of interventions during the campaign (it’s often best to limit this to just one such intervention). Thereafter, the PC can use this divine intervention to save himself or the party, perhaps by preventing an effect that would otherwise cause a character’s death, or to suddenly manifest an escape from a deathtrap. You, as the GM, have full power over how the intervention resolves, of course, so players won’t be able to use divine intervention to bypass plot elements you know they can handle—if a player tries this, simply tell him that his request for intervention is denied and that he can save his intervention for when it’s truly needed.

GM Fiat: The GM is the law of the game. His reading of the rules should be respected and adhered to. It’s easy to get hung up on complicated aspects of the game during play, but the game is never enhanced by long, drawn-out arguments over these complications between players and GM. When complications involving rules interpretations occur, listen to the player and make the decision as quickly as you can on how to resolve the situation. If the rule in question isn’t one you’re familiar with, you can go with the player’s interpretation but with the knowledge that after the game you’ll read up on the rules and, with the next session, will have an official ruling in play. Alternatively, you can simply rule that something works in a way that helps the story move on, despite the most logical or impassioned arguments from the players. Even then, you owe it to your players to spend time after the game researching the rule to make sure your ruling was fair— and if not, make amends the next game as necessary.

One handy rule to keep under your belt is the Fiat Rule—simply grant a player a +2 or a –2 bonus or penalty to a die roll if no one at the table is precisely sure how a situation might be handled by the rules. For example, a character who attempts to trip an iron golem in a room where the floor is magnetized could gain a +2 bonus on his attempt at your discretion, since the magnetic pull exerted by the floor helps pull the golem down.

Handling PC Death: Eventually, through bad luck or bad tactics, a player character is going to die in your game. Other events, such as petrification, paralysis, sleep, and stunning can have a similar effect on the game as PC death, and the following advice should apply to those effects as well.

When a PC dies, his player no longer has any input into the game (unless he has a cohort or other allied NPC he can start playing). That player has to sit at the table quietly, watching and waiting while everyone else continues to have fun with the game. In some cases, the effect is only temporary, with another player able to step in to restore the PC to life (or cure his petrification, remove his paralysis, or whatever), but nevertheless, when a player stops playing the game because his character’s been removed from the action, you as a GM have a problem on your hands.

When such an event occurs, keep going with the game; try to resolve the current conf lict or combat as quickly as possible so that the players can move on to addressing the problem of their dead ally. If there’s no way to restore the dead PC to life and the party needs to retreat to the city to pay for a resurrection, don’t delay that event by forcing the PCs to endure additional wandering monsters; just gloss over the return to civilization as best you can so you can get the unlucky player back into the game as quickly as you can. A PC death is often a great time to end the session, in fact, since you can then handle the resurrection details out of game via email.

If the player of a dead character prefers instead to move on to a new character, let him create his new character at the table. In this case, that player need not sit around bored—the act of creating a new character is involving enough that you can continue to run the game for the surviving PCs, after all. Once the player’s new character is done, let the other players take a 5 or 10 minute break while you step aside to talk to the player and learn about his new character, and to work with the player on a way to introduce the new character into the game as quickly and seamlessly as possible.

One other thing that PC death can do is bloat surviving player treasure. If your group simply splits up the dead PC’s gear or sells it, the surviving players can become obscenely over-geared for their level. If this doesn’t bother you, you should at least work to ensure that the new PC has gear equal in power to that now possessed by the rest of the party. It’s usually a much easier solution to simply assume that the old PC’s gear goes away, either being buried with his body or sent on to his surviving kin. One pretty handy way to solve the situation is to introduce the player’s new character as a prisoner that the PCs rescue, and to have the old PC’s gear be given to the new PC to equip him for the remainder of the adventure. Of course, this isn’t always a graceful solution, but it can be a good one to keep treasure levels under control until the new PC can sell off parts of his old character’s gear to purchase new gear. In this situation, consider letting the PC get full resale value for his gear, since you don’t want to penalize him for losing a character by saddling him with half the gear he used to have.

Rolling Dice: Some GMs prefer to roll all of their dice in front of the players, letting the results fall where they may. Others prefer to make all rolls behind a screen, hiding the results from the PCs so that, if they need to, they can fudge the dice results to make the game do what they want. Neither way is the “correct” way; choose whichever you wish, or even mix and match as feels right for you.

The only time you should not reveal the results of a die roll to the player character is when knowledge of the roll’s result would give the player knowledge he shouldn’t have. A good example of this is saving throws against effects that the player shouldn’t necessarily realize his character has been exposed to (such as a disease or a subtle, long-acting poison).

Troublesome Players: Play the game long enough and eventually you’ll find yourself with a troublemaking player—it’s just an unfortunate fact of any pastime that involves multiple people interacting in a team-oriented event. To a certain extent, you can rely on other players to help mediate problems with a troublemaker, but sometimes you’ll need to step in and ask the player in question to cease his inappropriate behavior. Don’t be afraid to ask the troublemaker to leave the game session if he won’t correct his behavior after a polite but firm request. If tempers are running hot among multiple players, don’t hesitate to call the game session early and break up, giving the players time to cool down and get over the event.

Campaign Journal

All Game Masters should keep a campaign journal. This can be a simple folder containing stacks of paper, a three-ring binder, a PDA, a computer, a tablet, a notebook, or anything else that you can keep notes in. Use this journal to record your thoughts and ideas related to the game as they happen, before, during, and after the game session. As you continue to run campaigns, you’ll doubtless need to expand your journal. Periodically, you should back up your journal, perhaps by copying the contents to a computer and saving them to a DVD, or maybe just by photocopying the contents and stashing the copy in a safe place. Nothing’s more frustrating than losing 3 years of campaign notes due to a crashed hard drive or a natural disaster!

Campaign Tips

Source PRPG Core Rulebook pg. 404
So now you have an adventure or two ready for your players to experience. While you can certainly keep these adventures as separate entities, and perhaps even have your players make new characters each time you start a new adventure, the Pathfinder Roleplaying Game assumes that your players will keep their same characters as they go from adventure to adventure, growing more powerful as they accumulate experience and treasure.

So, what happens between adventures? What is the world that those adventures take place in? Who lives there, and what do NPCs who don’t take part in the adventures do? The answers to these questions and more comprise your world, or setting, and the specific progression of adventures your PCs undertake in this setting is known as a campaign.

Many published campaign settings exist—the Pathfinder Chronicles Campaign Setting is the assumed setting for most games that use the Pathf inder Roleplaying Game rules, but it is by no means the only one. Dozens of publishers offer intriguing and detailed settings to choose from—you can even use settings from games that use rules quite different than those presented in this book, or settings that are inspired by or lifted directly from a favorite series of books or movies. But for some, the most rewarding part of being a Game Master is the act of creating your own campaign setting and running it for your players.

The act of creating a campaign is no less daunting than creating a world. It can quickly become overwhelming, especially when you start to consider all of the areas you’ll need to become an expert at. If your world has multiple moons, how does that affect tides? If you choose a specif ic shape for your main continent, what does that do to trade winds? Where do the deserts go, and where do the swamps go? How many rivers is too many? What impact would a technologically advanced nation of warriors have on the neighboring shamanistic barbarians? Does your world have chocolate and coffee and avocados? What’s the tallest mountain in your world, and why is it the tallest? Are there salmon and trout in your world, and if there’s not, what do the bears eat instead? If you have a nation modeled on ancient Japan, does that mean you need to learn Japanese in order to name NPCs who live there? Is there gunpowder in your world, and if not, why not? Is the world’s core molten? If it’s not, how would that impact your world’s magnetosphere—would there still be a north pole? How much does a longsword weigh if your campaign world is half the size of Earth? What happens if your campaign world is shaped like a ring?

For these reasons, it’s generally best to assume an Earthlike baseline for your first campaign world. Another handy tip is to avoid detailing everything at once. Staying just one step ahead of your players is often all you need to do—if you know that the first adventure they’ll be going on is an exploration of an abandoned fort, don’t worry about detailing anything but the surrounding 5-mile area, along with, perhaps, a small village for them to start the adventure in. If you know that the second adventure’s going to be in a haunted mine in the mountains, you then have as long as it takes the PCs to explore that abandoned fort to detail the area between your first village and the badlands to the east where the mine’s located. By creating only what you need to run the next few games, you slowly but surely build a larger whole, while at the same time maintaining your sanity.

Yet still, the lure of building an entire campaign setting is great. In a lot of ways, creating your own world is like an entirely different game in and of itself—a Game Master thus gets to play the game more often than his players, since when the actual session isn’t going, the GM gets to design cities and evil temples and nations and dungeons and monsters to his heart’s content. The Pathfinder Gamemastery Guide provides a wealth of advanced advice and tools you can use to build your campaign world, but the remainder of this chapter covers a number of different topics to aid you. These topics barely scratch the surface of the implications and ideas you’ll be facing when creating your own campaign world, but they can get you started.

Ending the Campaign

Source PRPG Core Rulebook pg. 406
In the Pathfinder Roleplaying Game, 20th level represents the top end of power most mortals can hope to achieve, yet this certainly doesn’t mean that your campaign needs to go all the way to 20th level. If you aren’t running an open-ended campaign where the PCs set the pace and the goals, you should pick a level at which you wish the campaign’s story arc to end. Talk this over with your players to make sure you’re picking a level range that they’re comfortable with as well. Note that you can also extend or shorten the length of a campaign by selecting a slow or fast XP progression. If you choose to run a campaign with a level cap of lower than 20th, consider placing your new level cap at a point where it feels like the last level achievable is something worthy. Oddnumbered levels are generally better than even-numbered ones, since most spellcasters achieve a new level of spell on odd-numbered levels. Multiples of 5 are good as well, since these multiples represent the last level before a new iterative attack. Stopping at 9th level is a good choice, since that allows the players to achieve capstone abilities like a bard’s inspire greatness, a druid’s venom immunity, a sorcerer’s 3rd bloodline power, and teleport and raise dead as capstone spells. Likewise, 13th level works well, giving capstone abilities like a monk’s spell resistance or spells like greater teleport, limited wish, and resurrection. Setting level caps of lower than 20th allows you to use them as soft limits—if your campaign’s story arc goes beyond what you’d originally planned, your players can continue to gain levels and new abilities beyond what you estimated. Since the classes presented in Chapter 3 don’t have additional rules provided beyond 20th level, setting a campaign arc to end at 20th level requires great timing and, invariably, some manipulation on your part as GM to make sure the story winds up before the PCs reach enough XP to theoretically hit 21st level.

Creating NPCs

Source PRPG Core Rulebook pg. 448
Aside from the players, every other person encountered in the game world is a nonplayer character (NPC). These characters are designed and controlled by the GM to fill every role from noble king to simple baker. While some of these characters use player classes, most rely upon basic NPC classes, allowing them to be easily generated. The following rules govern all of the NPC classes and include information on generating quick NPCs for an evening’s game.

The world that the player characters inhabit should be full of rich and vibrant characters with whom they can interact. While most need little more than names and general descriptions, some require complete statistics, such as town guards, local clerics, and wizened sages. The PCs might find themselves in combat with these characters, either against them or as allies. Alternatively the PCs might find themselves relying on the skills and abilities of the NPCs. In either case, the process for creating these NPCs can be performed in seven simple steps.