Dynamic Reaction Rolls

Thought it would be cool if an encounter had an ongoing Reaction to keep track of, while negotiating with NPCs!

You're going to want to roll based off of the dice your players are rolling to make checks. I use 2d6 so I'll roll 2d6, but for d20 you might want to use 3d6. We want a bell curve!

Instead of Reaction, we'll call this Tension. High Tension means that the NPCs are less likely to want to level with you, and might even pick fights. The neutral zone will be 6-8 on a 2d6 scale, and maybe 9-12 on a 3d6 scale. Low Tension means that the NPCs are pretty chill, and maybe even excited to talk to you.

Players can negotiate with NPCs to reduce Tension. If you have a roll-high system, you might want to have players roll + Charisma over the current Tension. You can give them advantage (reroll dice and take the better result) if they offer the NPCs something they want. Since 2d6 is a pretty small scale, on success you can just reduce Tension by 1. You might want to reduce Tension by 3 if you're using a 3d6 scale.

If players fail (or maybe just if they fail massively), you can increase Tension instead. You can even have players roll to escalate the situation and increase Tension instead.

Finally, players can make ultimatums with NPCs by making one final roll against Tension. This might be for the NPCs to let the players through their territory, to hire a potential follower, or to buy a really expensive teapot.