# Biggest GM pitfalls for new GMs? [closed]

What are the biggest/most common GM pitfalls (or mistakes) for new GMs?

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## closed as not a real question by AceCalhoonMar 8 '12 at 15:50

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I think one of the most common mistakes GM's make is making too many rolls.

Party comes up on a locked door. The door doesn't serve any dramatic purpose its really just a random locked door. Thief tries to pick but fails. Bard tries to pick but fails. Strong characters try to bash it down, probably fail. Break out the axes and start hacking, after an hour and a half of total play now they find it was just a broom closet.

If the door is really not adding anything to the game just give the thief an automatic success. I swear I have no idea how any thieves guild in any fantasy setting could ever make any money.

Another aspect to this is the GM that wants you to roll five sneak rolls in row and when you fail one all hell breaks loose. Part of this is people are just dumb at math and don't realize how unlikely five sneak rolls are for all but near 100% success. For example if your sneak chance is 0.5 (50%) the odds of successfully rolling that five times in a row is 0.5^5 (.5 * .5 * .5 * .5 * .5) or 0.03125 (3%). If your chance to sneak is .75 (75%) the odds of successfully rolling that five times is 0.2373 (24%). Even 0.90 (90%) is only 0.5905 (59%).

SIDE NOTE - don't confuse the odds of rolling a subsequent dice after the rolling some already. If you roll a 20 on a 20 sided dice, the odds of rolling a second 20 is exactly 1 in 20 or 5%. If you need to roll two 20's in row and have rolled nothing yet, the odds of rolling two 20's in a row is 0.05^2 or 0.0025 (< 1%).

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Focusing too much on the design of their game world or telling one particular story, and not enough on having fun.

Lightweight game systems like maxium game fun are a good antidote to this. The less time you spend designing things, the less emotional investment you have in them when the players want to do something that makes it all a waste of time. I think railroading pretty much always is a result of this.

Note that having a focus on game fun does not mean being nice to PCs. You are the source of all their troubles, remember.

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Sorry its a long post dont think I saw this. just general distractions. Someones house with other roommates so players and DM get side tracked often. Take official break for eating and drink etc as doing those while saves time takes away from the experience of the game and hard to restart.

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Switching Systems/Games

This is an issue that is easily carried beyond just "new" GMs, but it is common to become enamored with a new game, system, setting, whatever and go through the whole grass-is-greener syndrome.

I know I myself have done this several times, and I have been in groups where the GM has done this way too often. This issue very quickly alienates your player base and will prevent good gamers from showing up at your table.

I find that a good cure for this is to discuss with your players the desires of a particular game, understanding both what the GM and the players hope to get out of a scenario. While playing, always remember that roleplaying brings about many unexpected ventures, and while something else may seem "shiny" right now, you have no idea the amount of fun or change that your current game may bring. Make sure these goals are worked towards, and be sure to address any issues if these goals seem to be an impossibility.

Another potential cure is to stop looking at new material while playing a new game. This may be impossible for some fans of the hobby, but I find its very easy to dedicate one's self to a game if "roleplaying" becomes synonymous with that game, and that game only, for a short period of time.

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It's seldom a novice GM issue. And many people do want to play the right system for the genre. Then again, my 30 years gaming says those who hold to the "system is irrelevant" belief also tend to be in the "One univrsal system works for everything" camp, and complain about any change of system... And 99% of the time, fail to do the setting they mushed into their favorite system any justice at all. – aramis Dec 30 '10 at 11:06

Inability to say NO.

There are occasional players who can't help but one-up themselves at every opportunity. Their rogues cannot be introduced to a maiden without a seduction roll, their rangers cannot be introduced to a king without cracking wise, their fighters have never seen a peasant that they did not immediately need to brawl with, and their bards have never met with nobility without making egregious diplomacy checks for horrific goals.

While it is important to allow players to develop their character concepts, it is also important that you be ready, willing, and able to use whatever mechanisms are necessary, either in-game or meta-game, to preserve the flow of the game and the fun-factor of the OTHER players at the table.

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A lot of new GMs allow real world relationships to affect game balance, ie your girlfriend finds the coolest magic item, your best friend learns some special skill not available to the other players, the player you like the least doesn't get the benefit of a doubt on a fumble - the list goes on. More subtle forms of favoritism include giving some players more time to interact with NPCs, or roles within a storyline that are not earned.

Don't think you do it, but have a complaint or two that you do? Have someone (hopefully someone you are certain is going to be impartial) do a behavioral analysis of your session, measuring interactions rewards, punishment, positive and negative enforcement, etc on a night's session. Just use checks or ticks on a grid next to each participant's name.

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Ignoring the players

There is more to listening to your players than listening to their instructions for what their PCs do. Watch their body language. Are they bored? Players flipping through books, browsing the web on their smartphone, or dice stacking are potential symptoms of a problem. "Umm, what's going on?" when you ask for an action in combat is another possible symptom. Occasional symptoms are harmless, but if it's common you have a problem. If you have these symptoms, it's time to identify the core problem, after the game ask them what could be better.

pay attention to player-to-player discussions. This is an opportunity to find out what interests the players. As they make plans, you'll get a sense of what they like, what they want, and what they expect. You also get a chance to notice mistaken assumptions and can correct them before they become too entrenched. ("It must be a small dragon, it's a little cave entrance." "Umm, you can see the cave entrance, and it's fifty feet wide.") The catching mistakes is important enough that I got on more about it in "Failing to communicate the world" in another answer.

Pay attention to context. Why are they doing what they do? Ask if necessary, it's harmless. Do they refuse the help of an NPC who could benefit them? Perhaps they've had too many NPCs stab them in the back, so you (or an earlier GM) have inadvertently taught them to distrust all NPCs.

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Failing to communicate the world

To nick someone else's metaphor, you have a great big searchlight illuminating the world as it exists in your head. Everything is obvious because you see and know all. But the players are working with a flashlight, based on what you tell them, what the books tell them, and common sense. It's very easy to assume that something is obvious when the players don't realize it at all. In particular, what about things that the character should obviously know, but the player might not? It might be knowing the proper way to address a noble, or it might be as fundamental as "what time of day is it?"

The solution isn't to describe everything in excruciating detail. Instead, pay attention to the players' plans. When they discuss something that sounds insane, ask why they think that's a good idea, why they think it will work. That will usually quickly identify any gaps in understanding. When they announce that they do X, and X makes no sense in context, again, ask why they're doing X, what they think it will accomplish. When you identify gaps in understanding, things that the characters should reasonably know, clarify. Whatever you do, don't punish them for their misunderstandings.

A real example of how it can go wrong: At a convention game, we're the SWAT team for a local police department. Rich people aboard a large yacht for a party are taken hostage by terrorists. What do we do? Well, we arrange a black rubber raft and dress all in black. We're going to quietly paddle up to the side, wait for the patrolling guard to pass, then climb up and disable him from behind. "Great," the GM announces, "as you paddle up, the guard sees you and raises the alarm!" What? How did he see us? "Well, your black raft and black clothing was pretty visible in the middle of the day."

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Mixed expectations

If you and your players have different expectations about a game, it can be very, very frustrating. To take some real examples:

I thought I was playing a more cinematic Vampire game, the GM erred on the side of realism. A heroic boot-first leap into the windshield of an oncoming car left my character briefly stuck in the windshield.

I ran a My Life With Master game. I failed to clearly communicate that it's a game of personal horror, of being weak and being pushed to be horrible. The players got more of a slightly goofy, "Hey, we're Igors and monsters!" vibe. Everyone was frustrated and one player was very angry as they were not interesting in playing someone who did terrible things.

I signed on for an Eclipse Phase game where we were told we would all start as crew on a freelancing cargo transport/smuggling vessel. Most of the group went in expecting and designing characters for a Firefly-like game with lots of travel. When the GM destroyed the ship in the first adventure, it was quite frustrating.

Make it clear up front what sort of game you'll be running. And that means that surprises are bad. Surprises within the expectations are cool. Surprises that change core setting or genre assumptions are very, very dangerous. By way of example, I'm tinkering with a BPRD (Hellboy) campaign inspired by Witch Hunter Robin. (Spoilers for Witch Hunter Robin follow.) My original plan was for the twist (that the BPRD is destroyed and the PCs go from legal law enforcement(ish) to guerrilla freedom fighters) to be a secret. But my experience since makes it clear that someone signing on for a BPRD campaign could be very frustrated if I take the the BPRD/law enforcement part away. So I plan on spelling out the broad picture in advance.

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Not Saying "Yes"

A lot of times, a new GM wants to "control" the game. And saying "no" is a great way to control what is happening in your game.

One example I can cite is we were playing SpyCraft 2.0 and my character wanted to purchase a stretch mini-cooper. I wanted a vehicle big enough for the whole group of characters, and I thought a mini-cooper would be fun and funny as a stretch limo. The GM said "No" and then one of the other players went on the internet and found actual photographs of stretch mini-coopers. And the conversation devolved at that point. I felt bad, but the whole thing had snowballed out of control by then. The point is, there was no real reason not to have one available (except that the GM admitted they thought it was a stupid idea and that they shouldn't exist). Whereas saying "Yes" and moving on would have been just as interesting and the game could have moved forward. Don't get me wrong, you will need to say "No" more than you will need to say "Yes", but don't let it build up into a habit where you just automatically say "No" to any idea that you can't immediately predict how it will turn out.

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Saying Yes reflexively is as bad as saying no reflexively. – aramis Jan 7 '11 at 0:47

Giving players exactly what they ask for!

Quite often, players will have goals for their characters. Allowing them to achieve those goals is good. Giving them their goal on a silver platter in the first session or two is not. Achieving a goal after much hard work is good. Giving them the goal with minimal conflict is not. Giving the characters exactly what they were hoping for is boring. Giving them something that keeps the spirit of what they asked for, but is very different, is interesting.

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Houserules & Options

A common problem for novice GM's is coping with house-rules and options choices: both theirs and their former GM's.

Many novice GM's forget to tell players that they've made a change in the rules, or which optional rules are in force.

Many novice GM's don't realize that some part of the game mechanics in play was actually their GM's house rule, and then encounter a rules lawyer going "No, that's NOT how it works," creating a trust issue.

Occasionally, a novice GM will wind up with more houserules than rules, and not realize it is time to either change game systems, or rewrite the houserules into a standalone game.

The solutions:

Make certain one keeps track of one's houserules, and which optional rules are in play. Write them down, and make copies available to players, especially experienced players new to one's group.

Look at one's body of houserules. If it's just one or two, or a series of rare but important special cases, its a non-issue. If, on the other hand, it's several typed pages and making drastic changes used often, perhaps one really doesn't like the game system they're hung upon.

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This is great advice, don't change the rules until you have a solid grasp of how they work and what changing them will do to your game. – dindenver Dec 7 '10 at 23:28

Mismatch of Game to Gamers

Probably the hardest to overcome, and the most pernicious throughout gamerdom, is mismatched game and gamers. Different games have different mechanics and levels of mechanics because people's tastes differ.

The most common breakdown, the "Gamist-Simulationist-Narrativist" paradigm presented by Ron Edwards, looks at it from how the rules approach game play. It's one part of the larger picture, but there are some games which try to present accurate simulations, others which try to encourage, or even enforce, narrative structures, and others still which focus on being a competition or game to the partial exclusion of narrative and simulation. If you don't have the right system for their desires, the game may go well, but often will be less satisfying.

Another part is rules detail and rules precision. Some people want, or even need, detailed mechanics. The very idea of "off the cuff" rules calls is a problem for them. Others hate looking things up, and the very idea of more than a straightforward and flexible process become problematic. Even in narrative focused games, some, like Mouse Guard or Burning Empires, have lots of precise rules. D&D is noted in the current edition for lots of detailed rules; it's not a good simulation, and it's not very narrative in focus, but has LOTS of detailed rules. But one can get a very similar but-kicking tactical game feel in 1/4 the core-rules-pages by playing Warhammer FRP 1st or 2nd edition... or by playing Palladium Fantasy.

With a new GM, the problem is compounded: Most novice GM's don't know what their own preferences are, let alone their players' preferences, and further, seldom have a range of systems to pick from on their shelves.

This can be mitigated somewhat by experience with other types of gaming. If you like your boardgames simple, a page or two of rules only, you're unlikely to enjoy a highly detailed set of mechanics with special case rules galore. On the other hand, the guy who plays boardgames with 100 page starting rulebooks, and 500page advanced ones, is more likely to enjoy the rules for everything.

Likewise, some GM's naturally gravitate towards chopping some parts of a ruleset out, and plopping in different parts to alter the feel or focus. This also can mitigate the issue of mismatch. But realize also: if one's made rules mods, new players need to be made aware of them, since there is an issue of broken trust for many players when they find out that the rules at the table aren't the ones in the book.

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A new GM will often have a specific plotline/storyline and expect that the players will follow the path you have planned out. This is often not the case, despite clues, hints and anything else you have left for the players which make it obvious to you as the creator which way they should go. To the players, it's often not as obvious (since they don't know the end game) or sometimes they know, but don't have a motivation to follow the path you want them to. The solution for many new GMs (and some experienced ones) is railroading (i.e. forcing the players to follow the path you've set/planned out).

While this is, on occasion, useful. It's bad practice to make a habit of it. Be flexible ready to change things on the fly if the party doesn't follow your planned route. If they go a whole other direction, be prepared with various ways you can encourage or guide them back around to where you eventually want them to end up. Or be prepared to take the campaign in a whole other direction (at least temporarily) when needed.

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Don't be too scared if the players come up with something totally different then what you planned. Sometimes this can turn out to be something really awesome and fun! Play along with them and sometimes they can come up with something that probably was a better idea and they feel acomplished for working out such plans! – The Jug Dec 6 '10 at 18:51
@The Jug: Absolutely. Some of the best sessions I've run have been where the party when completely off the plan within the first 15 minutes and I had to wing things as we went. Just do a bit of preparation for when they do. One tip, though: If you do find yourself winging it, take notes on what you have added to the campaign by doing so. You can find those things coming back up later, especially if a PC asks you about something that happened. (Which has resulted in me making stuff up a second time once or twice...) – BBlake Dec 6 '10 at 19:32

One of the toughest GM pitfalls: saying "No".

You are ultimately there for the entertainment of your players; keep that goal paramount. Their enjoyment is more important than the plot, the NPCs' goals, historical consistency, all your hard work, and even adherence to the rules. Ideally they should go hand-in-hand, but when they don't, it's your task to try and find a way NOT to say "No."

It can be as simple as, "Yes, but there will be a big negative modifier to the die roll, and you'll take damage if you fail". Or, it could serve the narrative in interesting ways:

"Yes, you can execute the unconscious prisoner, but his fine clothing suggests he's worth more alive than dead, and he has powerful allies."

"Yes, the archmage will agree to help you, but you suspect his price will be heavy."

"Yes, against amazing odds you've managed to slide the expensive-looking ring off the baron's finger. But as you hold the heavy ring in your hand, it seems to be...calling your name? You feel an overwhelming desire to slip it onto your own finger..."

This is not to suggest there should be no limitations, just that limitations should serve the players' enjoyment. Try to put the decisions in the players' hands. Determine consequences, not boundaries. Try not to say "No."

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Saying "No" is not a bad thing (despite the numerous games which give the "Yes, But" or "Yes, And..." advice). It's saying "no" for the wrong reasons. "No" is the right call when a player is attempting something that is, within the scene framed, utterly implausible, or is explicitly not possible in the setting or mechanics. Like jumping a ship to a planetary surface in Traveller, or a mortal doing aggravated damage to a Vampire with a punch in Vapire: the Masquerade. ——¶—— No has its place, used in moderation. ——¶—— That said, "Yes, But" and "Yes, And" are better most of the time. – aramis Dec 7 '10 at 22:57

Setting oneself up as "opposed" to the PCs. While most conflict is between NPCs and PCs, there is a difference between them. The NPCs are there primarily to provide assistance or opposition to the PCs, but that doesn't mean that the GM should be opposed to the characters (nor, indeed, over-generous with assistance).

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There are a number of games where the GM is explicitly there to oppose player actions; the most blatant and explicit is Burning Empires where it really is players vs GM. – aramis Dec 7 '10 at 20:41
This is true, but such systems are largely the exception rather than the rule. Most RPGs require a degree of judgement and restraint from the GM, and I've certainly seen inexperienced GMs fail to realise that the right level of challenge is the one that maximises everyone's fun. – Dave Hallett Dec 7 '10 at 21:10

"Why are we doing this, again?" quests.

In response to @Pulsehead's comment on Mary-sue NPCs, at least you have the possibility of the players treating him like a gandalf-bazooka (also an excellent reason not to have high-powered NPCs tag along).

The most prototypical "Why are we doing this, again?" quest is the escort quest, especially those modeled after MMO quests have the players escorting a feckless, worthless, no-body of an NPC across incredibly difficult terrain because the plot says so.

I, myself, have endured these, and pondered the feisability of cutting off the escortee's head, casting the preserve-corpse spell of that edition, hustling over to the destination, and just reviving him.

Quests have to make sense, and they have to be worth the risk, and they have to be fun. Moreover, they need to present at least one real choice (defined as consequences), otherwise the players are just roped along for the ride.

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+1 for DMotR reference. But to defend my NPC, he wasn't a plot-bazooka. Essentially, two countries were at war. There was an unknown third party instigating the two countries. The PCs learned of a string of destroyed villages in their country, and get the mission to go to the other country. They find out that there are a few destroyed villages THERE as well. Investigate while the Ambassador negotiates the peace, and then bring evidence of the third party to the negotiations in time to tip the balance towards a peace treaty. – Pulsehead Dec 7 '10 at 2:01
Well, a limp-noodle is in many ways worse than a bazooka. While a short amount of making sure the noodle doesn't get into trouble is fun, unless it turns into a "March Upcountry" (by Weber) style saga, it's not entertaining in the long run. But this conversation illustrates quite neatly that extremes on either direction are just boring. :) – Brian Ballsun-Stanton Dec 7 '10 at 2:04
This entire question could arguably be answered as "go read DMotR". It's mostly in there somewhere! – Dave Hallett Dec 7 '10 at 21:15

Figure out your 1 greatest flaw in making PCs. This flaw will bite you in the behind almost constantly. For me, it's names. So here I am with this wonderful map and a great plot for an adventure, but naming (my great flaw) still needs to be done. There are almost no names on my map, and to combat the urge to name things "thus-and-such" or "blah-dee-blah", I realized I had to name everything forseeable in the next 2 sessions, but then add a print-out of appropriate names, and whenever used, I'd mark that the blacksmith in Izzleheim was Gorfnyr (both names pulled from my actual list, btw).

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Yeah, figuring out what your blind spot is can be super important to a new GM. It is not always naming the NPCs. But that can be hard if you are not inspired. For instance for me it is demonstrating characters motivations when their motivations aren't simple (like greed or bloodlust). Like in my mind it maikes sense, but sometimes the players don't grok it and then they don't know what to do with this guy (or gal).... – dindenver Dec 8 '10 at 20:20

Underestimating your players: Whenever you've got encounters with enemies, you've got one brain coming up with ideas for your baddies, and the players have several brains figuring out how to deal with them. You are outnumbered and will sometimes be outthought. Accept that. Let them have an easy time now and then if they earn it. Try to avoid throwing in additional difficulties ad hoc because the bad guys don't do as well as you'd thought, although if the players start on a course of action you're not prepared for you can think of problems they'd encounter.

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Not disagreeing, but sometimes throwing in additional difficulties can be beneficial. If all the enemies go down easy, the players get bored, and there's nothing easier to fudge than a few more hit-points. – C. Ross Dec 7 '10 at 13:33
@C. Ross That's really system/playstyle-dependent. Games where tactics aren't important (or non-existent!) don't suffer when the bad guys go down easy, since the enjoyment is located elsewhere in the game/system than in tactical challenge. – SevenSidedDie Dec 7 '10 at 20:05
Plus, there's the issue in many indie games of players narrating up the opposition, such that the GM doesn't actually have a choice over the encounter. Or can use the narrative controls to deny the GM access to reinforcements (by defining the reinforcements are non-extant, or stuck behind some other issue). But in such cases, the fun is, as SSD notes, lying elsewhere. – aramis Dec 7 '10 at 23:02

Allowing and Giving Insufficient Descriptiveness

P1: I swing at Orc #1
GM: 20 - you hit, double damage. P2, next!
P2: I move to the 3rd orc, and swing. 18.
GM: You hit P2: 4 damage.

Such bland narration is fine in a miniatures game, but in an RPG, it's going to become a problem.

Good
P1: I swing my poleaxe at the Orc with the big falchion. I got a 20.
GM: Your swing connects with a sickening crunch, somehow missing his shield. Double normal damage. P2, what's Ferd doing
P2: Ferd's Charging the orc with the snarl...
GM (interrupting): he spots this and says, "Come and get it!" and the snarl becomes a snaggletoothed grin
P2: When I get there, I try to smash him with my warhammer. 18. 4 dam.
GM: "You'll have to do better'n dat, oomie..."

The little bits of color text, while they do slow down play, often make play far more interesting, enjoyable, and memorable.

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In reality as I encounter it such descriptions fast become annoying and the players demand to go on with the fight. – Mnementh Dec 6 '10 at 16:38
It really depends on the game and the group. Your "speedy" approach would be completely unacceptable to my players, so it's horses for courses here! – Dave Hallett Dec 6 '10 at 18:38
Agreed Dave - I have found my group prefers more description. In fact, I have yet to have them complain about too much description. – aperkins Dec 6 '10 at 21:29
But would this not be a matter of preferred style, rather than pitfalls/errors per se? A more accurate pitfall might be failure to find out what level of description is best for the group. fwiw, my group prefers color when color is more useful and appropriate, as in settings & clues... but not during melee. – ExTSR Dec 6 '10 at 22:42
Unless you're into minis-game mode, probably not. My experience is that, over the last 30 years, I've never had more than 1 player in a group complain about more, and everyone else complained about him. So, No, Frank, I don't think it's really a style issue for 99% of adults. In fact, it's YOUR own advice... (Basic Set, no less!) There is such a thing as Too Much... but that's, for me, when I'm having to come up with more than two sentences a combat action. In case you haven't noticed, verbosity isn't my weakness... but it's an attention span issue for players. – aramis Dec 7 '10 at 4:15

Oops! We all make errors in games... of technical mechanical points, of judgment calls in variable situations, and many more. The novice GM often lacks the experience and judgment to correct and/or resolve errors quickly without disrupting the flow of the game. Many new GMs have not learned that the rules are less important than the fun.

When an experienced GM makes an ad-hoc ruling which is technically at odds with 'by the book' rules but does so in a way acceptable to the players, and in so doing keeps the game going smoothly, then the fun of the game is maximized, and a disruption of the mood (delay for checking rules) is avoided.

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This is a big help! I DM on my laptop and have an OO doc open that has: What sucked tonight? What rocked tonight? What did I not know tonight? Any time I do something REALLY well, really poorly, or can't find a rule in under 2 minutes of digging; I type it into that document. Next day or two, I go over that file and figure out what I did well (and try to work more of that situation into the game since it's fun), figure out how to fix what I did poorly (to make more fun), and look up those pesky rules I forgot about (to keep it going next time). – Pulsehead Dec 6 '10 at 13:47
I think I know what you mean here, but would you consider an edit to make it clear exactly what the pitfall is here? Something like "Worrying too much about getting the rules exactly right, and spending too much time looking them up"? – Dave Hallett Dec 7 '10 at 22:47
If, as a GM, you can sort of inspire that collaborative spirit from the rest of the group, then you can rely on the group to help you find the correct answer. Or, in the worst case, allow you to make up an answer so we can keep playing. – dindenver Dec 9 '10 at 23:28

I have seen a lot of research fail in Earth games set up. Normally (but not only) Geography and History.

If you are planning a plot in some away city or continent, you should at least see the wiki site for that place and look at a map of said place.

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Common(ish) Pitfall: Mary-Sue NPCs

This is usually seen in new GMs who can't let go of having "their" character. The Mary-Sue NPC is wonderful at everything, seemingly invulnerable to harm, and in the worst cases completely takes over the game. The end result is that everybody is bored except the GM, who has effectively dispensed with the need for any players, except possibly as an audience.

Temporary "plot immunity" for some NPCs is sometimes desirable (although see "railroading" in a different answer). But if you're not prepared to see harm come to an NPC at some point, they should be very peripheral to the game, at best. And flawed characters are generally a lot more interesting and convincing than people who are perfect in every way.

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One way to ensure this is to give your NPC some MAJOR flaw. I created an ambassador that the PCs had to escort to a peace negotiation. He was useless in: combat, horse-riding, camping, cooking, hunting, and foraging. – Pulsehead Dec 6 '10 at 13:54
Similar to Pulsehead: if an NPC is adventuring with the PCs, make sure they aren't better at any area that a PC has made their focus. e.g. Don't have a super tracker NPC join the party if there is a ranger PC, least the ranger player get bitter. But, if no PC cares about an area, an NPC expert is okay. No PC took tracking? Okay, Bob The Super Tracker will be welcomed. – Alan De Smet Dec 9 '10 at 21:37

Common Pitfall: Underestimating (occasionally overestimating) how much time is need to play a given scenario/section/etc.

While sometimes players will find an ingenious way to short-circuit the rough scheme you had planned, and thereby leave you woefully short of prep, the more common problem is that what you thought would take an hour or two of play to get through actually takes more than twice as long, particularly if your players are fond of lengthy in-character conversations.

It's very difficult to predict how much time is required for a given adventure, and people who have been GMing for 20+ years are still struggling with it. Be very sceptical about any time estimates you make!

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Yeah, I try to not estimate how long things will take anymore. I try to have a few encounters/scenes ready, or else I try to make sure that I have too much stuff - less work for the next week then. – aperkins Dec 6 '10 at 21:27

Common pitfall: Going overboard.

I've seen a few PCs turned GMs who approach the game as a greedy player. They're the ones who will run a game for all denizens of the World of Darkness instead of running a Vampire or Mage game. Or they'll start a triple gestalt D&D game with all published books and Dragon magazine allowed. I think the attitude is that they're giving everyone what they want, because it's something that they wanted to play. But the result is unfocused and badly powered.

I'm not saying that new GMs shouldn't be ambitious, but they need a good understanding of how the game works out of the box and why that's the default setting, before making so many big changes.

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Yeah, this can either be super awesome or superbad. If the GM knows the rules in all the boooks and has a way to tie all the different setting elements together, it is great. Otherwise, it is a recipe for disaster. – dindenver Dec 9 '10 at 23:29

Common Pitfall: Overreaching everything.

It's tough work being a new GM. You have to keep up with N players and M monsters/NPCs. That is potentially N x M interactions. New GMs almost always overdo it. Enthusiasm can take you only so far.

Solution: Ask the players to help - with rules - with session logistics (food, playing space, etc.) - with details, and even with plot. Most importantly, be honest with them and HAVE FUN! What makes RPGs different from all other games is that there is no way to 'win' that doesn't involve everyone having a good time!

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