During the course of a gaming session, unusual events may occur that threaten to bring the action to a screeching halt. A GM must know how to handle these situations; this sub-Chapter briefly goes over how to handle irregularities when they arise.
Of course, the best way to handle irregularities is to minimize the potential for their occurence. The best way to do this is to know the players in the group and to discuss any conventions (table rules) the group would like to employ before the session begins. Such conventions include topics as what to do when problems with dice occur (what happens when they fall off a table, what happens if they don’t land properly on a rolling surface, etc.), what will happen to a PC should their controlling player not be able to attend a session (they will be run by another player, played as an NPC by the GM, be absent from the current adventure because of some sort of plot reason, “fade into the background”, etc.), and any proposed rule changes.
Another way a GM can avoid irregularities is to know as much as possible about their adventure before it begins and to keep track of what materials they will need while it is ongoing. References to be used during the course of the adventure should be selected and agreed upon before it begins. A GM should know as many of the Core Rules as they can (or at least be able reference particular topics quickly); the Core Mechanic in particular is an essential piece of information. Finally, a GM should be able to quickly reference the stats of the player characters; preferably, they should have access to their own copies of the character record sheets for purposes of tailoring encounters between sessions. Knowledge is key to avoiding problems altogether.
Keeping the balance of the game is a tricky job that every GM must deal with. No one character should be significantly stronger than the others (the only exception to this might be when a character has had advanced training and another hasn't). If one PC can zap the bad guys with a single blow, none of the other players get a chance to fight, which leads to group boredom. Tailoring encounters with that character in mind would be disastrous, as it's likely that none of the other PCs are sufficiently advanced to deal with the threat. If a PC becomes noticeably unbalanced, there are two ways to deal with the problem. The first is to try an in-game solution. Some of these may include having the high-end character catch some major illness that reduces their abilities to match the rest of the group, or perhaps creating antagonists that can resist the advantages of that character (while being vulnerable to the abilities of another character in the group). GMs should be careful when doing this not to mention that these events are occurring to correct the game’s balance (and should work not to make it obvious that's what is happening). Otherwise, the player might become deeply offended; they probably worked very hard to make the character as strong as they are. The second option is to try and handle the problem outside the game. This option is riskier but may be worth a try if an obvious in-game solution is not available. The GM may simply explain to the player that they believe their character is too powerful and work with them to try and tone it down. The problem with doing this is that any future attempt at an in-game solution will seem contrived if the player refuses to adjust their character; it’s always better to try in-game solutions first.
A job that will probably come up in a gamemaster’s career is teaching players new to the game how to play. New players shouldn’t worry too much about the game’s intricacies, but it is important to teach them about the Core Mechanic (roll d% and hope for a low number, as discussed in Chapter 1.1), as well as how modifiers work and any other basic rules required to understand their character. Gamemasters should read up on Chapter 2.3 and know the rules for creating a new character. They should then sit down with the new player, ask them what kind of character they want to play, and then walk them through the creation process. New players may need hero points to in order to get them caught up with the group; that's fine as long as the new character ends up with slightly less capabilities than everybody else. As for the game's intricacies, they can usually be taught on a case-by-case basis. New players and new characters will need to be integrated into both the player and character groups; simple introduction usually suffices for player groups, while a plot device that introduces the new character to the group works best.
It may also happen that, through people becoming bored, angry, busy, re-located, etc. that a player will have to leave the group. It’s up to the GM as to what to do with their character(s). They can either continue as an NPC, be written out of the plot of an ongoing campaign, held as a reserve character, be killed off, and so forth. Sometimes a GM may choose to assign multiple characters to a player if the group gets too small. They must be sure, however, that the player is up to the task of controlling multiple characters. Otherwise, this solution can create more problems than it solves.
From time to time, it is possible that the GM will have an unforeseen problem with their adventure. If the problem is with a description of something that's occurring, the GM may attempt a more visual solution (such as drawing a sketch or finding a picture of what is being described). Making maps and props is a good way to describe things (and it has the added bonus of giving the players an object to connect with a description). Visual aids may be prepared at any time during an adventure, though they are perhaps best created outside a gaming session.
Other times, however, the problem is with players doing things that the GM didn’t anticipate (players aren’t playing in character, picking up on the ostensibly obvious clue, have thrown away the item that would've allowed them to finish the adventure, etc.). In this event, the GM needs to quickly think up a series of events that will get them back onto the story's path. Any contingency planning will work, even the inclusion of a minor sub-plot. If the GM is at a loss for ideas, they can try listening to what the players are talking about and go off of that. If all else fails and the story is completely derailed, the GM should be gracious enough to admit that fact to the player group and ask for time to think up some way to get things back on track. In the meantime, the players can do other activities such as going out for movies or for snacks. It’s better to have the group doing something, rather than for them to have to wait in boredom for the GM to come up with ideas.
Above all, a GM must be willing to work with the players on any issue that comes up. If a GM shows that they are willing to work with the players, if they’re consistent in applying the rules, if they don’t take sides in an argument, and if they are clear that their rulings are not vindictive, the players will trust the GM and the decisions they make. When that happens, everyone can rest in the knowledge that any major problem will be ironed out smoothly and quickly.