No.
Bad GM.
No cookie.
Okay, we’ve been talking about things GM’s shouldn’t do for awhile now. So let’s talk about the elephant in the room: Fudging.
The most common form of fudging, and that from which the technique takes its name, is changing the outcome of a die roll: You fudge the result. If the die roll is done in secret, then you can just ignore it. If it’s done in the open, then you can invert the result by tweaking the modifiers involved. More advanced fudging methods can include stuff like adding extra hit points to a monster’s total in order to keep them alive.
But, regardless of the specifics, fudging is when a mechanical resolution tells you one thing and the GM chooses to ignore the rules and declare a different outcome.
JUSTIFICATIONS FOR FUDGING
Okay, let’s talk about the reasons GMs do this. All of these, of course, ultimately boil down to the GM not liking something that the resolution mechanics are telling them. The question is why the GM is unhappy with it.
#1 – Railroading. This one is pretty straightforward: Railroading happens when the GM negates a player’s choice in order to enforce a preconceived outcome. Enforcing failure (so that the PC can’t do what the player wants) is a really common way of railroading the game, and fudging is a really easy way to enforce failure.
See The Railroading Manifesto for a lengthy discussion of this topic and all the reasons why railroading is terrible and you should never do it.
#2 – To prevent a player character’s death. Or, in some cases, GMs will only fudge if it’s to prevent a total party kill — the death of ALL player characters. TPKs tend to kill campaigns (at least those not built around open tables), and lots of people would prefer to fudge the outcome of a fight (particularly if they feel that it’s just due to “bad luck” or whatever).
See The TPK Gamble for a specific discussion of this.
#3 – To make the story “better.” The most infamous version of this is, “But they can’t kill the Big Bad Guy now! He’s supposed to survive to Act III!”
I say infamous for good reason here: Players hate this shit with the fiery passion of a thousand burning suns. And you basically can’t throw a stone in RPG circles without hitting someone who has a story about the time their GM pissed them off by doing it. Check out The Principles of RPG Villainy for a better alternative.
#4 – To correct a mistake you’ve made. Maybe you’ve been screwing up a mechanic for the whole fight and it’s made things much harder for the PCs than it should have been. Or you accidentally doubled the number of guards when the fight started. Or, going even further back, maybe you just screwed up the encounter design and something that should have been easy for the PCs is actually incredibly difficult. So you fudge something to bring it back in line with what it was supposed to be or should have been.
This is actually pretty understandable, and I discuss the difference between openly retconning a mistake and silently retconning a mistake in Whoops, Forgot the Wolf. But you can easily find yourself slipping from “fixing a screw-up” to “enforcing a preconceived outcome” here and end up back in railroading. So use caution.
DON’T FUDGE
In the end, all fudging is the GM overriding a mechanical outcome and creating a different outcome which they believe to be preferable (for whatever reason).
Over the thirty years I’ve been doing this, however, I’ve learned that many of the most memorable experiences at the table are the result of the dice taking you places that you never could have anticipated going. Fudging kills those experiences.
But what if the mechanical outcome really is terrible and would make both you and your players miserable?
If you and/or your players truly can’t live with the outcome of a dice roll, then you made a mistake by rolling the dice in the first place. You need to focus on fixing that problem.
This applies beyond individual dice rolls, too. If you don’t want the PCs to die, for example, why are you framing scenes in which death is what’s at stake? (This is a rhetorical question: GMs do this because D&D teaches them to (a) frame lots of combat scenes and (b) make the default stakes of any combat scene death.)
The Art of Pacing talks about the scene’s agenda being the question which the scene is designed to answer. (For example, “Can Donna convince Danny to go into rehab?”) If the question is, “Will the PCs die?” and the answer is always, “Absolutely not.” then the scene is drained of meaning and becomes a boring exercise.
This is why, when the players figure out that the GM is fudging (and they will), it deflates tension and robs them of a legitimate sense of accomplishment. What was once meaningful is suddenly revealed to be meaningless. And this is the biggest problem with fudging: It may fix an immediate problem, but it will inflict permanent damage on everything.
In a very real sense, fudging is a betrayal of trust. And once you, as the GM, lose the players’ trust, it becomes virtually impossible to regain it. Fudging ends up tainting everything you do: It removes the real magic of an RPG campaign and turns it into a cheap magic trick. Once the players spot the trick (and, again, they will), the magic vanishes entirely and you’re left with a hollow experience.
Regaining their trust and making them believe in the magic again is really difficult.
TRIAGE AT THE TABLE
Here’s my controversial rule of thumb:
The more you fudge, the shittier you are as a GM – either because you are fudging or because you need to.
If you’re not just fudging to be an asshole and screw over your players, then you’re ultimately fudging in order to fix something that has gone wrong:
- You adjudicated the resolution poorly.
- You designed the scenario badly.
- You screwed something up and need to correct it.
- You’re using a set of rules which creates results you and/or your players aren’t happy with.
And so forth.
This is not to say that you should never fudge. Mistakes happen and we don’t need to live with those mistakes in the pursuit of some unrealistic ideal. But every time you do fudge, you should view that as a failure and try to figure out how you can fix the underlying problem instead of just continuing to suck in perpetuity:
- Don’t roll the dice if you can’t live with the outcome. (And, ideally, learn how to still create meaningful stakes instead of just skipping the resolution entirely.)
- Figure out how to design robust scenarios that don’t break while you’re running them.
- Create house rules to permanently fix mechanics that are creating undesired results. Or, if the system is completely out of line with what you and your players want, swap to a different system.
And so forth.
Next time you find yourself in a position during the game where you feel it’s necessary to fudge, I want you to do a couple of things.
First, ask yourself: Is it truly necessary to fudge in this moment? Is it necessary to reject the improvisation prompt of the mechanical resolution’s outcome, or can you find a way to work with that outcome to create something interesting and enjoyable? At the stage in the resolution process where you’re narrating outcome, you usually still have a lot of power as the GM. An easy example of this is failing forward: Instead of the PC failing in what they wanted to do, they succeed with a negative twist or consequence.
But also, to a certain extent, just take a moment to second guess yourself: The outcome which you initially think cannot possibly happen, often can happen. It’s just not what you expected or would have done of your own volition. Try to push back that initial moment of rejection and really, truly think about what the outcome would be and whether there’s interesting and cool stuff that lies beyond that outcome.
Second, ask yourself: Can I just be open and honest with my players in this moment? Instead of secretly fudging the outcome, could you just explain to the players that, for example, you screwed up the encounter and things need to be retconned a bit?
And maybe you can’t! There are circumstances where you’re better off plastering over the cracks of your mistake with a cheap magic trick instead of damaging the players’ immediate immersion and engagement with the game world. It’s not ideal, but sometimes that’s the best you can do for right now. You’ll just have to learn from your mistakes and do better next time.
CODA
If you’re still a proponent of fudging, let me ask you a final question: Would you be okay with your players fudging their die rolls and stats and hit point totals?
If not, why not?
If you truly believe that fudging is necessary in order for you to preserve the enjoyment of the entire table, why do you feel you know better than the other people at the table what they would enjoy?
Think about it.
This is an excellent expression of the no-fudging position, and I agree with nearly all of it.
The bit I’m not sure about is the question in the “Coda”. There are lots of ways in which the traditional-rpg GM role is very different to the player role, and these differences often involve secret knowledge, greater discretion, and a responsibility to try and “know better than the other people” wrt what they will like.
I’ve found the shift in D&D editions has really increased the amount of fudging expected by the players.
As the game has changed away from dungeons and the wilderness, becoming more about expansive narrative and character stories, players have become more and more attached to their individual characters.
Back when I started GMing again in the late 2000s, I had players come to the table with a level 1 character with 3,000+ words of backstory and a lot of player attachment – who then subsequently die in the first session.
The expectation from some players has changed, they want nigh unkillable ‘chosen one’ heroes. Yet they also want to play D&D, rather than a system that actually supports that from the get go.
Two words: DM Fiat.
The DM is there to provide a fun play experience.
The players will need to trust their DM to provide same.
Each contributes to the whole, but the DM has the power to change anything on even so little as a whim.
Either the people involved are having fun, or they’re not. How they got there isn’t the point, as long as everyone is having fun.
@Baron:
And what about robbing the players of the fun of knowing that their decisions are meaningful, as opposed to having the consequences of their actions artificially engineered by the GM – fudging – in contrast to the result of the dice?
@Baron & @Bruce:
I don’t think any resolution lies in the direction you’re going, because Baron’s fun-first, DM-fiat position hinges on an assumption that the DM knows their players’ wants and needs very well, and then deploys very general goal of “fun”, which we can take off in all kinds of directions. Is fun the same as satisfaction? Amusement? Relaxation? Immersion? Engagement? Within this framework, Bruce’s point about players possibly wanting to make meaningful decisions and have a consistent world to play in can simply be absorbed as a different variety of “fun”, and we’re left saying, “Well, whatever is fun for this group of players, that’s what the D&D DM must do to be successful.”
Since the extremes of “The DM decides what will be most awesome and that happens” and “The DM and the rules set the parameters and then the dice fall as they may” are both ways we can approach a tabletop pastime, I think we need to ask what rule systems and game structures best advance the style we’re trying to achieve. The Baron seems to have some attachment to a version of D&D, and I have to ask myself why. Is it just the flavor of the PC options, monsters, magic items and established settings? Those can be easily ported over to a looser set of rules that don’t require frequent DM fudging or outright negation in order to let the referee control the game. Like Justin says, “If the system is completely out of line with what you and your players want, swap to a different system.”
The thing that I find most confusing about this idea of, “Let’s play a game with the D&D rules, but with the understanding that the DM will make whatever they like happen whenever they think it’s a good idea,” is that it seems to advocate using the rules only in situations that don’t really matter, and abandoning them when the stakes are highest. If anything, I’m inclined towards the opposite: don’t roll for events that will certainly succeed or fail, or are of no consequence, and consult the dice when an outcome is unknown and important.
I do think some players prefers the GM to fudge to keep their character alive. I think it comes from two mutually exclusive wants; they want the thrill of the uncertainty that their character may die, but they also want to keep playing the character. “Save my character for me, but don’t let me know”, fudging accomodates that.
Personally I don’t fudge and roll most of the dice publicly, but I’m not judging others for fudging if that’s what their group wants.
I have fudged, but not in the ways mentioned. I’ve fudged when I roll who in the party gets attacked by the big bad. Allowing the wounded to be bypassed in favor of those more likely to survive.
I don’t know if there is even a rule on how to determine who the enemy attacks but typically I decide who is in range and split it up evenly. So I’m fudging my own rule. Also it seems logical an enemy might attack the greater threat.
Ruprecht — That raises an interesting distinction between “rules” and “GM-advisory procedures”. We don’t have to make that distinction, and most games don’t explicitly, but I think it’s useful.
Random encounter rules are something that’s often meant as GM-advisory, even where designers assume the GM will strictly follow the other rules.
I tend to treat my own random encounter etc rules as advisory, so I may or may not follow them in any given case. But (a) I try to stick to them most of the time, or explicitly change them to match what I do in practice, and (b) if the game was designed to be about tight resource-management using random encounters as a key element of that, I might treat them as rules and refuse to fudge them.
(In your case, though, it sounds like there is no written rule or procedure at all. So I’m not sure how it’s fudging in any sense.)
I think Ruprecht makes a good point of a gray area for fudging: Sometimes, you want the players to get the information “This is potentially really deadly” without killing them outright, and sometimes the first opportunity to do so might be with a warning shot. (Of course, this could be the fault of the GM for not seeding the info earlier, but it could also be the fault of the players for not searching for info, and this warning shot is now the GM’s mercy. Is either a clear symptom of bad GMing? I wouldn’t say so.)
And then, if the dice roll, they might suddenly come up with a result that goes beyond “warning” to “killing”, and the GM doesn’t like that, because the entire point of that warning shot was to get the message across in a way that allows people to still react to it. Fudging the dice then to make that shot barely lethal? Maybe sometimes appropriate. (Not forever, sure. If the players refuse to learn that being cautious beforehand saves them from getting into these situations and start relying on that first attack always not killing, then by all means, up the stakes.)
Good article. Avoiding situations in which one would be tempted to fudge and not being attached or wedded to ordinary outcomes negates the need for fudging.
But I have a situation where I will engage in open fudging with support of players: a long string of bad rolls from a player. When I say long string, by this point, the player’s bad dice rolls cause groans and venting about those rolls from other players and themselves. I have a player whose Roll20 rolls seem to be the result of pissing off their RNG somehow. I don’t like to do it, but at my tables we agree all happier with rare interventions, because otherwise people get burnt out from effectively sitting and doing nothing in a session because of an low probability outlying series of results.
Alien@System, that brings up the other fudging I did. I added an NPC or two to the party to provide help provide additional muscle (never perception or knowledge type stuff). The group got to like the NPC as if they were actual PCs but they were there to take the first blow if I ever wanted to send a warning that the PCs weren’t getting. I was a kid then, and it worked, but I should have had better clues and foreshadowing so it wasn’t necessary.
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On the subject of warning shots/first blows, it seems like demonstrations of restrained power can work just as well as the real deal. A skilled gunslinger could shoot a cigarette out of a PC’s mouth to demonstrate accuracy. A Force user could choke someone to the point of unconsciousness before letting go. It comes back to one of the essay’s main points: if you don’t want the stakes of that attack to be lethal, don’t frame it that way in the first place.
I can agree with everything except the CODA.
There is a big difference between what a player thinks they want, and what they actually want. As in any game, the players will do what they can to achieve their goals. The GM on the other hand is above that, he IS the game, and should seek to make a fun experience.
Let’s say you have a newly created party, and the GM thinks the players know what they really want. The Cleric has the motivation of finding his lost sister, so he goes looking for her as they get to the big town. If the player really knew what he wanted, he would be happy finding her, right? The rogue wants money to buy some new equipment, so she breaks into a house and finds 1000 platinum pieces. The Sorcerer wants to become more powerfull, so an arcmage in the town teaches him his ways, and the sorcerer immediately advances to 10th level.
Did they get what they wanted? Yes. Did they get what they REALLY wanted? No, they did not have fun. In PvE games, it has always been the player against the game. It is the job of the game to not give the players what they want, but to make them fight for it, make them uncover great secrets they never could have imagined. Just like it is the job of the player to strive for what they want: power, wealth, or their lost sister.
So to anwser your question: “Why do you feel you know better than the other people at the table what they would enjoy?”
The GM knows better because it is his role in the RPG, to know what people enjoy, and give it to them.
“It is the job of the game to not give the players what they want, but to make them fight for it”
Sure, players want the challenge of achieving their goals and it’s the GM’s role to present that challenge in the form of obstacles. Fudging is about the GM reaching for a preconceived resolution to those obstacles, rather than letting the players overcome them through their own means. It’s shifting the goalposts rather than setting them properly to begin with.
If players really wouldn’t enjoy certain consequences to failing at their goals, it’s more honest, less arbitrary, and less immersion breaking to simply take those off the table. If, for example, they legitimately wouldn’t enjoy the specter of death, what’s wrong with just giving them enemies that offer chances to surrender before attacking? If they wouldn’t enjoy capture, give them enemies that offer no quarter.
I can’t fully agree with fudging being so bad, especially when it comes to things that aren’t dice rolls. In my D&D campaigns, I fudge hit points, AC and stuff like that all the time. Hell, the most memorable and fun encounters I ever ran according to my players was an encounter I started without any prep. I just made up stat blocks on the fly. As long as it is consistent in the moment, its fine. I don’t need to know whether my bad guy has an AC of 16 or 17 if my players haven’t had the opportunity to figure it out. Once they do know, of course, it has to remain consistent. Nothing’s worse than shifting numbers the players can “see”.
Ultimately, I guess I don’t see why its better if I decide on the exact number of hit points before the session or during it. It’s arbitrary either way. Dice rolls, of course, are different as they are happening in the moment and they are also my form of letting go of control over a scenario. If the dice decide A, then its A.
Overall great article though, I agree with most of your points when it comes to dice rolls. Just not about DM chosen mechanics such as the stats of a particular creature.
@Dragotarify
I think what you’re describing is improv rather than fudging. Nobody can or wants to plot out every detail of their setting, and I think most players understand if you have to come up with stats on the fly. Like you say, setting the initial benchmarks for a challenge feels different than adjusting them after the fact to force a particular resolution. The boundaries can blur if the GM inserts arbitrary obstacles or spoonfeeds assistance, but the intent does matter, and players can distinguish between good faith improv and bad faith fudging.
@ Bruce Capua
Lots of fudging critics trot out the idea of fudging making player decisions meaningless – That ignores the possibility that fudging can make player decisions meaningful by revising the results presented by the truly arbitrary force at the table – the dice.
Example: Characters are trying to scry a potential enemy and gain some intel, but he makes his saving throw – can’t be found by the sensor. So they engage in a plan to obtain a closely held personal item and significantly undermine his save, but he still gets one and can potentially succeed at it. Arbitrary die roll won’t care about the preparations the PCs went to or how good their plan is – they may have improved their odds but in D&D/PF there’s still a flat out 5% auto-succeed. My decision as GM – I was going to fudge the roll he succeeded in his save. THAT’s fudging to support player decisions and plans – that’s making sure they are meaningful when the die doesn’t really care.
It’s true that fudging can steal away a player victory. But it doesn’t have to. It can be used to promote and support player agency against outrageous results.
In the example above you don’t have to fudge. Just declare that you are overriding the rules and not rolling for it. In adjudicating the action, decide it can’t possibly fail and do not roll for it at all, that’s not fudging.
I agree with Pelle: If die rolling could produce an “outrageous” result that doesn’t make sense, and the roll serves no dramatic purpose, skip that die roll. That is a situation where the rules work against you. If it makes sense for the characters to succeed, but none for them to fail, then they auto-succeed.
Tell the players that they succeed before they roll anything, but then let them roll to determine how difficult is was to achieve that success. “You got a 4 on your Survival check? Your efforts to trail the orc horde are successful, but you are delayed by over a day by the need to avoid a pack of hyenas that had also been following the orc tribe, scavenging from the trail of debris and animal remains the tribe left in their path.”
I would like to see a blog entry regarding alternatives to dying. When we talk about fudging to avoid pc-deaths, i keep thinking how to work the lost battle into a story that goes on. I have seen mechanics where dying isn’t the usual outcome to loosing, but a drop in prestige, unless its something really important, and then the players get a bonus because now everything is at stake (i think it was Warbirds)
Excellent article! By the number of comments I see that the topic is as controversial as ever 😉
I’d add my own rule of thumb: fudging die rolls is only acceptable under one condition, that *all* participants of the session agree on how, why and when GM can do it.
(That said, I agree with all arguments against it, if dice roll is fudged clearly something went wrong…)
@Jack Deer
Invisible Sun by Monte Cook Games has some interesting ideas about character death. The cliff notes are that when you die you become a completely passive ghost and slowly become more self aware and able to interact with the world, until you eventually pass into The Pale to live as undead (with no implications of alignment).
Powerful beings, which is to say the player characters from level 1, can choose to not pass into The Pale and instead exist as ghosts for as long as they want, gaining increasing control. There is also a number of character advancement options for speeding up this process.
This means that intentionally dying can be a valid tactic for things like recon (ghosts can move through walls, become partially corporeal to activate with objects, and move about generally unsseen).
Death becomes more of a story beat that your character is going through, rather than the end. Even a TPK is just a shift in the narrative, albeit a drastic one!
@Justin Alexander
Just a heads up, the link to Part 10 on the series is a dead link!
Thanks for all your pieces, been enjoying this site for the last month or so now (this might be the last series on the site i haven’t scoured over, outside of the running the campaigns’ series.)
There’s a lot here to disagree with:
Doesn’t the GM have an editorial responsibility to the content?
I frequent fudge HP, either tossing a few morelogs on the fire for a major adversary, or applying the mook rule to either expedite combat, give a particular character a “win” moment, or simply because I pulled a quick stat block and it’s damage output was adequate, but it simply wasn’t designed for what I needed and I can’t custom make every encounter the way I’d like to.
Dropping a DC by a point, giving a character a “rule of cool” bonus that doesn’t exist RAW, or making a certain goblin have 7 hp instead of 9 certainly is fudging, but hardly represents the betrayal of the integrity of the game presented here.
A GM is a host and an MC. If the show is killing it with the crowd, you can milk it. If it’s going poorly, you can parachute out.
And yes, these are mechanics I’m interested in giving a player too: the flashbacks of Blades in the Dark, the dice in FATE, and the inspiration, hero points and plot point systems of 5e are all strong tools that players should be allowed access to. These are all fudging tools, on top of in game mechanics that grant advantage, allow rerolls, give you a floor on results, etc.
I agree that you shouldn’t be railroading, but accusing GMs of poor design when fudging can be an ELEMENT of design, an improvisational tool for emergent situations that allow you to reduce the heavy lifting of calculating the odds of your fighter going on a cold streak and let them kill something in the fight where a bard is cleaning up with vicious mockery finishing blows while the rogue keeps nailing sneak attacks because the fighter was adjacent.
@Fistan most of what you describe isn’t fudging by Justin’s definition (or mine).
Jeez…
I can’t believe this is still going on.
I thought they removed that part about the DM being the “master of the game” from the newer DMGs.
The single, most basic question you, as a fudging DM, need to ask yourself is this: If you’re going to fudge, why roll dice at all? Just tell your players that you’ll play by DM Fiat and, if they agree, if they have FUN, carry on. Why hide it? Why pretend?
Read some of those “the social contract of RPGs” articles, either here, or anywhere else.
Fudging DM: “But, but … randomness is FUN! Randomness if flavor! I do not know *everything* about what happens in the game.”
No, just the important parts.
Fudging DM: “It’s clear that you’ll miss and the villain will get away because he’s fun and I want to reuse him. Roll to see if your bolt shatters the window on his left, or the vase on his right, as he makes his escape through the door at the end of the corridor.”
Ok, tell your players that you’ll play with DM Fiat, but with un-fudged flavor dice. The slider for what constitutes “flavor” can go quite far either way, but make it clear ahead of time.
Are all side quests flavor, and you’ll only fudge on “main quest” encounters? Is combat with minions flavor, but BBEG fights are not? Or even, perhaps, BBEG fights are rolled openly until they get to a certain threshold where you take over and dictate the result.
Tell all this to your players before you start playing, and if they accept it, you’re golden. Thing is, unless you raised them from pups and trained them well, your players will not readily accept it.
Mike.
I fudge(d) rolls. Not often, actually only to prevent death of a memorable PC, that had a great idea and horrible luck with the dice. Maybe once or twice in 30+ years? Even then, the character went into a coma instead of dying (it was World of Darkness: dead is dead, a coma… well, it triggered a fun chase after the ambulance that tried to take the PC to the hospital)
I still feel bad about it, but I also find it difficult to judge harshly GMs that fudge rolls sometimes. I don’t think it’s always a failure as GM. Most of the time, yes; always… not really.
Since those “early days”, I learned not to use death as the only outcome for a battle: Running away, crippling injuries, loss of an essential artefact or being made prisoner are also “being defeated in combat” outcomes.
I’ve done it, we’ve all done it.
I once needed a big ooze monster for a short side-adventure for my lv 18 3.5 party. I took Juiblex, stripped him down to about CR 19, and ran with it. It all went fine until one of my players spotted the page in my book (Peeking is bad!) and noticed that I was using a modified version. He talked me into using the full stat block (the situation was already bad for his peeking at my materials)
So the campaign ended in a TPK after almost 4 years because I let a player talk me into “fudging” a monster into something worse against by better judgment. They were strong, but any Demon Prince would have wiped the floor with them, much less Juiblex. This is infact what happened. Despite the fact that Juiblex had no business oozing up out of a village well in the dead center of nowhere.
I’ve since learned not to modify monsters on the fly out of the sourcebooks, nor to tolerate players sneaking a glance at my notes.I don’t get why he wanted that. I was using encounter-based XP (a sort of halfway between tallying up xp for every monster and milestone) so there was no XP benefit to using a higher CR stat block.
It was a bad end to what had been a legendary campaign. 9/10, Fudging is bad news.
I’ve seen other articles here where @Justin has said basically that changing what you put in your DM prep notes after play begins is fudging. I can’t agree with that entirely. To me, if something hasn’t hit play, it isn’t locked in. It’s probability curve hasn’t collapsed into the present moment.
A monster that has appeared in the encounter is locked in, no changing what’s prepped there, it’s in play. But if a player thinks of something I didn’t, and it’s plausible, such as speculating about a clue that’s better than my own prepped clues, then I see no reason why I wouldn’t run with it if it seemed like a good idea.
One thing I’ve realized recently is that fudging and railroading are essentially the same thing, or at least the two edges of the same sword.
Fundamentally, in a roleplaying game there are three sources of narrative input: the players, the GM, and the dice/rules/resolution mechanics. In a good game, these will constantly be trading off: the GM describes a situation, a player describes what his character does in response to that situation, the dice describe what happens as a result of the PC’s actions, the GM describes how his NPC reacts to the new situation, the dice describe what result the NPC’s actions generate, and so forth.
Railroading (as Justin has defined it) is when the GM negates the player’s narrative input in order to enforce his predetermined outcome. Fudging, then, is when the GM (or a player) negates the die’s narrative input in order to enforce a predetermined outcome. The two are fundamentally the same thing, happen for the same reasons, and produce all the same bad outcomes and side effects. They both undermine the fundamental alchemy of roleplaying games: the ability to make meaningful, associated choices and be surprised by the outcomes.