50/50 Heroes S01E18 - Battle of the Wits

Animated comedy series. Sam is due to take part in an eloquence contest whose prize was won by her mother and her grandmother when they were young - the pressure is on Sam, and that makes her unbelievably tense. Sam realises that she is lost for words when she feels stressed - to avoid catastrophe, she asks the Sceptre for the power of repartee. The half-power does provide her with snappy answers, but they are extremely caustic, and that's just the start of her problems...