Terror strikes me as rather heavy-handed here. I’d be more inclined to base it off Rapier Wit. Instead of Public Speaking, roll against Combat skill at -2 (Average Technique can buy this up to Combat Skill +2), appropriate Combat Art or Performance, or Intimidation, for Fast, Graceful, or Vicious, respectively. Based on
this thread, I’d call it [10] in a campaign where Rapier Wit is normally available, [15] or [20] otherwise. The first price has Words of Power +100%, treats changing it from Hearing-based to Vision-based as +0%, and treats having to link it to an actual attack (instead of being a free action) and not needing a few rounds of setup banter as a wash. The latter prices basically just tosses in an Unusual Background.