A way to control a crowd of npc's

[w01fe01]

say there is this guy, hes a great speaker, maybe for his religion, or just a cause. PC's come and try to grill him on info.

what abilities could i make this character have that could rouse the crowd he had into a frenzy and have them attack the PC's to allow the speaker a chance to escape?

[VRMH]

That seems to be tailor-made for the Demagogue Bard.