[RPG] Can a persuasion roll avoid battling the BBEG


So yesterday I was DM’ing our weekly D&D 5e session. For practical reasons it was a one-shot. At some point, one of my players, a Lvl 10 Bard, ends up in the BBEG’s lair alone (an adult red dragon, CR 17). Partially his fault for ending up alone (because he tends to act impulsively), but that’s not really relevant here.

So the player wanted to persuade (+13) the dragon saying “I come in peace". I argued that, seeing as there are explosions happening all around caused by the party (and some suicidal Molotov-cocktail Kobolds), there is no way he’d fall for that. He then asked me to let the dragon counterroll insight (which, for a dragon, is only +1). Even when I gave the dragon advantage on his insight roll (20), and the player disadvantage on his persuasion roll (21), the player still won (yup that’s the effect of a +13).

So I thought to myself “fair I’ll give him one round, so he can try to get out” and let the dragon fly up. But one round later, the player did not try to get out nor try to call out to the rest of the party, instead smugly believing he nailed it. So then in this second round, the dragon said “did you really believe I fell for that?” and breathed some fire over him. The player was however not amused, and said this wasn’t supposed to happen because he won his persuasion roll. We continued the game anyway (“ok ok you’re the DM”), but kept on discussing about it until the end of the session; he really felt he was treated unjust.

I am really wondering if I acted wrong, and how I could have dealt with it in a better way. I particularly don’t like the ensuing discussion afterwards, as it slows down the game a lot (and makes me hesitant of putting them in nasty scenarios even when it’s partially their own fault).

Some thoughts:

  • an adult red dragon is a smart and arrogant tyrant. I felt it to be really in character to let him believe for 1 round that he was persuaded.

  • I found the role playing for the persuasion rather weak. I’d have been more keen to follow his plan, if he’d say something of interest for the dragon, like “I can spy for you on the nearby town”.

  • From a game mechanic point of view, should it be possible to persuade your way out of boss battles? That seems very flat and boring, but with his +13 persuasion he’s gonna succeed most of the time

  • Does the roll difference matter? He only won by one more than the dragon’s roll (which was one of my arguments why he’d realise very fast anyway)

I’d love to get some insight on how you’d have dealt with this.

Best Answer

You are the DM, you decide the rolls

The problem was when this happened:

He’d then ask me to let the dragon counterroll insight (which, for a dragon, is only +1).

Why is the player dictating to you when rolls happen? As the DM, you are the only one who should call for rolls. Even if the player presumptuously rolls for persuasion, for example, it doesn't actually count unless you say it does.

Remember that dice rolls are to determine an uncertain outcome. If the outcome is certain (i.e. "there is no way he'd fall for that"), then there's no need to roll.

From PHB, p. 174:

The DM calls for an ability check when the character or monster attempts an action (other than an attack) that has a chance of failure. When the outcome is uncertain, the dice determine the results.

Although the above quote mentions failure, the same is true of only rolling if there's a chance of success. From DMG, p. 237 (borrowed from Szega's answer):

When deciding whether to use a roll, ask yourself two questions: Is a task so easy and so free of conflict and stress that there should be no chance of failure? Is a task so inappropriate or impossible - such as hitting the moon with an arrow - that it can't work? If the answer to both of these questions is no, some kind of roll is appropriate.