It’s not cheating. It’s really not.
My good buddy Vanir recently posted a lament for his innocence over at Critical-Hits. You see, Vanir has recently began filling the role of Dungeon Master and he’s having to grapple with the reality of how situations tend to unfold behind the screen. It’s approaching a decade since I first took up the mantle and began running games, and one of the cardinal rules of filling this role was summed up concisely on page 18 of the 3.5 Dungeon Master’s Guide in a section titled “DM Cheating and Player Perceptions”:
Do you cheat? The answer: The DM really can’t cheat. You’re the umpire, and what you say goes. As such, it’s certainly within your rights to sway things one way or another to keep people happy or keep things running smoothly.
Other editions of the D&D rules have stated the case in similar but slightly different ways, and ultimately the responsibility comes down to you and the DM to take the appropriate action to keep the game fun or running smoothly. Please note: this does not define what “keep people happy” or “running smoothly” means. In my games, I considered my plot an outline… a mere suggestion… so that the players can choose to stay in the lines or to color way outside them. Vanir often chose to color way outside the lines, onto the table, all over the walls, and perhaps two or three houses down the block. I have always enjoyed letting my players define the world that they act in to a certain extent, allowing them to define where the railroad tracks get laid down to get the story from point A to point B.
So what’s a man to do?
To address Vanir’s problem specifically: every good DM cheats. The trick is to provide the players with enough breadth so they don’t necessarily see you cheating. For example: we’re fighting a long battle. The players are expending their abilities and skills and it is depleting them, but not far enough that they are in any real danger of dying. Could I run this encounter out to the very last hit point that the bad guy contains? Sure I could. Would it be boring, providing that the bad guy can’t really do enough damage to exhaust the group? Absolutely. So you fudge the bad guy’s hit points a bit to make the encounter end.
What I don’t like doing is (unfortunately) what Vanir did in his campaign: not being used to his players acting off-script, he magically teleported them to the next plot point. There’s nothing really WRONG with doing this, but I do like some cause and effect to occur if the players act differently than they should have. Just leading them to the next battle or skill challenge can feel pretty obvious to the players and take them out of the story. I’m not beating up on Vanir any more than he already has himself, but better ways to deal with this type of situation mostly come with experience. Figuring out a few contingency plans for what will happen if the players don’t take the plot hook or interact with NPCs in a non-ideal way will help to smooth these bumps.
The other main thing that Vanir mentions in his article is the loss of innocence from being a player. Now you KNOW the fudging that can occur, and you start to ask yourself if every fun or exciting moment in a campaign was because of the DM acting to favor the players in some way. The only advice I can give is this: sit back and enjoy the ride. Have some caffeine and sugar, and let the game unfold.
It’s actually pretty fun sitting in the player’s chair again to see if you can detect when the DM is making stuff up. I’ve found a few of them have a “tell”… they shuffle some papers, roll some dice that have no outcome on the encounter at all, or stare at the players with a blank or angry expression when things aren’t going as they anticipate. It’s also fun to see how they resolve the situations as well, you can learn something from their responses too. If I possessed the insane ability to play off-script player characters like Vanir does, I would be doing that all the time and see how the DM reacts.
But back to the main point: you never really can “un-know” the fact that the DM does some trickery to make the game move forward. Just know it’s part of his job, and it’s part of your job to enjoy the story and be invested in your player character. That’s the real fun anyway… building up a hero based on your own imagination. There’s no rule set or die roll that should affect that aspect of roleplaying games one bit.