D&D 5E How do you rule on NPC-to-PC social interactions?

[Cap'n Kobold]

Scenario: NPC sells weapons. He claims that his greatsword is of special quality (but the DM knows the guy is a liar), and wants to sell it to the PC at 5x the listed price in the PHB, even though in reality it's just an ordinary greatsword.
The PCs are interested to buy a greatsword, especially if it has special properties (and let's assume they cannot check it for magic properties and aren't proficient in smith's tools).

Now the NPC makes a deception check and rolls a natural 20, for a total of 27. Does that mean that the PC must now buy the sword at 5x the market price, even if the player behind the PC suspects that he's being deceived? I would consider that player "forced" to buy that sword.

I think that the player should have freedom to refuse that sword at all times, no matter what the DM rolls. It's up to the DM to put up some decent roleplay. And in addition, the player can attempt to see through the lies with an Insight check.

The character may well believe that the sword is worth what the NPC is asking for it, but they are free to decide that they just don't want an extra-expensive sword, and ask the NPC if they have anything cheaper.

Have you ever noticed any meta-game gotchas? Such as the PC knowing they just rolled Insight and experiencing a degree of internal dilemma? That might not be a strong, subversive or bad faith dilemma.

It might be something like - I may have been going to lean into not trusting this NPC, but now that I have rolled Insight it's hard for me to do that with a completely clear conscience, so I guess I better just trust them.

Generally no. Because I have both the Characters' passive Perception and Insight available to be, even if I ask for a roll, the player may not know what it was for.
If I'm expecting to need that sort of thing, I have asked the players to make some D20 rolls before the session begins, and I will apply them to whatever checks needed.
However, most of my players are pretty good roleplayers and so that sort of precaution is generally unnecessary.

 

[Bill Zebub]

That sounds like the players are interested in buying a superior sword but the DM rolled a Deception versus passive insight and the NPC succeeded.

I would run that straight with giving no indication that he is trying to pass off something as what it is not. On a fail on the deception check I would have told them that something seems up with his pitch about the superior quality of the weapon.

No need to force the players to do anything.

Rolling to deceive the players into buying a faulty sword would be a different situation.

Right. The DM can certainly rely on a dice roll to decide how to present information. Assuming the goal is for the PC to believe it’s a quality sword, there are two ways to go about this:

A) Tell the player, “I have determined that your character believes X. Please roleplay accordingly.”
B) Try to make the player believe X.

Why would anybody choose A?

 

[Baldurs_Underdark]

Right. The DM can certainly rely on a dice roll to decide how to present information. Assuming the goal is for the PC to believe it’s a quality sword, there are two ways to go about this:

A) Tell the player, “I have determined that your character believes X. Please roleplay accordingly.”
B) Try to make the player believe X.

Why would anybody choose A?

I guess that's exactly my point.

The DM can always roll to see how well that particular NPC is going to handle a situation. But it shouldn't affect how the PC has to roleplay - ever.

 

[clearstream]

Also, if the roll determines what a PC knows, believes, etc., but that doesn’t require (or prevent?) any actions…what was the point?

If it’s just for roleplaying, can’t people just roleplay?

For those with what are sometimes described as neo-trad leanings, one point can be to make facts about characters more relevant to play. It gives a pay-off for a player for their character choices, and enables them in some sense to the enjoy the character they wanted to enjoy, even if they might not be themselves great at - or even deeply worried about - doing the roleplay part. Game qua game, in essence.

 

[Umbran]

So, let's see...
An NPC can leave a PC in no doubt about their fine art, with a CHA (Painter's supplies) check.

Charisma is about the moment of interaction. So, if the PCs watches the NPC paint, this might work. If the NPC is selling art in a gallery, that becomes about Persuasion or Deception. Either side having tool proficiency may give advantage on checks in this instance.

An NPC can pry information from a PC, with a CHA (Intimidation) check.

Not quite. An NPC can intimidate the PC with a CHA (intimidation) check. Then, when the PC gives an answer to a question, I am apt to give the NPC advantage on their Insight check to know if the PC was lying.

 

[clearstream]

I guess that's exactly my point.

The DM can always roll to see how well that particular NPC is going to handle a situation. But it shouldn't affect how the PC has to roleplay - ever.

A case I find striking is where an NPC passes themselves off to PCs as someone they are not. I genuinely believe the strongest way to RP that is to give zero clues to the players, not even rolls, so I would likely make checks against passive Wisdom (Insight).

To me - and I acknowledge views diverge - this is saying something about what the character thinks. They think that NPC X is NPC Y. That will likely impact their roleplay, even unwittingly. It doesn't rob them of agency, but misinformation is slippery like that. Choices one makes on the basis of misinformation aren't the same choices as those one might make with (true) information.

Hence it's a case I am interested in because I see it as borderline. Is it okay? Is it not okay? What do people feel is going on?

 

[clearstream]

An NPC can pry information from a PC, with a CHA (Intimidation) check.

Not quite. An NPC can intimidate the PC with a CHA (intimidation) check. Then, when the PC gives an answer to a question, I am apt to give the NPC advantage on their Insight check to know if the PC was lying.

I quite like that. The supreme torturer can't make you talk, but they sure as hell know if you lie to them.

 

[iserith]

A case I find striking is where an NPC passes themselves off to PCs as someone they are not. I genuinely believe the strongest way to RP that is to give zero clues to the players, not even rolls, so I would likely make checks against passive Wisdom (Insight).

To me - and I acknowledge views diverge - this is saying something about what the character thinks. They think that NPC X is NPC Y. That will likely impact their roleplay, even unwittingly. It doesn't rob them of agency, but misinformation is slippery like that. Choices one makes on the basis of misinformation aren't the same choices as those one might make with (true) information.

Hence it's a case I am interested in because I see it as borderline. Is it okay? Is it not okay? What do people feel is going on?

I describe the NPC as they appear, offering subtle clues that something is off during the interaction. Just like I would telegraph the presence of a trap in a dungeon. The players, if they're paying attention, can then take action to tease out what's going on. Their stated actions might result in a Wisdom (Insight) check or perhaps Intelligence (Investigation), if that best fits their goal and approach.

 

[Voadam]

I quite like that. The supreme torturer can't make you talk, but they sure as hell know if you lie to them.

That's not really the way that works.

Torturers usually elicit responses, but are no better off on knowing whether they are actually lied to or not. Most responses will be emphatic and as convincing as possible to get the torture to stop, whether they are actual confessions or false confessions because that is what the tortured person believes the torturer wants to hear them say.

 

[Bill Zebub]

I quite like that. The supreme torturer can't make you talk, but they sure as hell know if you lie to them.

Which is exactly the scenario I presented in the other thread.

But it only really works if the player genuinely wants to avoid the consequences.