|Some angry mob eye candy found on Wikipedia.|
The word lynching has an interesting history, but that's not what this post is about. Lynch mobs are a strong trope in (old) horror movies and literature. Be it Frankenstein or Dracula, depending on the version you're reading or seeing, both were overpowered by angry townsfolk at some point. Why not have something like that in D&D? Something fast and simple, maybe?
Easy Lynch Mob Recipe
You'll need more than 13 really angry townspeople, but not more than 100. Add torches and pitchforks. Mix with other agrarian tools as desired. Use with a breeze veterans, if available. It's not necessary, but good for the flavour. The number of agitated people is the percentage to resist any magical or spell-like attempts to influence the crowd. Reduce percentage by spell level multiplied with 3 (multiplied with 4 against spell-like abilities).
Serve at night and near the next local vampire or evil wizard. Enjoy!