aboyd
Explorer
So... did you punish the players because you didn't like their potion-buying? Did you change the fights in any way from their original form?he later approached me and complained about the battles being too tough. I got attitude because of their lack of thought-process in buying potions in town. I told him "These battles are set to be apart of this module, they are how they are, and you guys had every opportunity to load up on useful equipment before you left."
If you did, the player has a right to feel annoyed. People can pick up on a DM being punitive, even if the DM tries to play it off as innocent. If you're running a published module, you can bet that at some point in the future, he's going to take a look at it. If he sees something different from what he experienced -- especially if you claimed that the fights were exactly as the module described -- he's going to have a legitimate beef with you.
It's not that you can't change things -- I almost always do. However, I go out of my way to not appear to be punishing anyone. For example, if a player in my game loaded up on spells to affect the undead and I had changed a module to use fewer undead, I might tiptoe around that one. I might reconsider. I don't want the player thinking, "I planned logically for a tomb raid, and now it's like the DM meta-gamed against me and removed every typical tomb monster!" You know? You don't want to do things such as taking note of a player's skills and then deliberately circumventing those abilities.
If a player is naturally super-effective in some games and super-ineffective in others, well that's the way it goes. But if it's un-natural, if its uncanny how things appeared to be built to bypass the player's skills, then ouch. Someone is going to complain. If you didn't modify things, great, you were totally fair & honest, and the player needs to suck it up in that regard.
Yeah, I do that a lot, and it works. It was difficult at first because I didn't know the exact right words to use to end a discussion. I kinda wanted to grab a problem player, shake 'em hard, and shout, "SHUT UP SHUT UP SHUT UP!"I agree with Roguerouge, listen to the argument once then make a call you can live with for the rest of the session. Then at the end of the session you can discuss it in depth.
Those would have been the wrong words.

So I found the right words were simply to say, "I need to keep things moving. This is house-ruled for the duration of today's game. We'll review the books later, but no retconning."
That has almost always worked. Most of the time, house rules are just as fair as the book rules. So people aren't arguing that you're unfair (usually). Instead, they're arguing that your rule conflicts with known procedure and they don't know how to settle into a conflicted state. Give them permission to let things be conflicted, by telling them it's a temporary ruling.
There are just a few times when this failed. Usually, the players have a cow only when the house-rule will utterly destroy their expected course of engagement. In those cases, I generally relent, break out books, and spend a half-hour discussing a bunch of boring rules. But that's rare.
Every now & then you might decide that your house-rule is better than the book rules, and you'll want to make your temporary rule a permanent one. In those cases, you have to be prepared for fallout, and handle it gracefully. I made a ruling once that changed how effective a particular class was. The person playing that class wanted to completely abandon the character and start over. I let him. If you nerf a class or spell and then force a player to keep using the now-crappy class, those players will feel cheated.