Factual error: When Bender is dipped in the baptismal oil the oil level in the barrel doesn't change; which it should because of the Archimedes Principle. (00:10:20)
Roswell That Ends Well - S4-E1
Factual error: There were no nuclear tests anywhere near the Roswell Air Force base in New Mexico.
Anthology of Interest 2 - S4-E3
Factual error: When human-Bender is dancing in the disco with the two girls there is a fully lit disco ball which manages to cast no light beams on the walls and floor, as they normally do.
Factual error: During the flashback of 2000, Fry's family is watching the Rose Bowl. Fry's mom, a Wisconsin fan, shouts "touchdown!" Then we see the score on the TV. Wisconsin 9. Standford 3. 2nd Quarter. However, Wisconsin never led 9-3 and didn't score a TD until the 3rd quarter. It was Standford that had the 9-3 lead in the 2nd quarter.
Teenage Mutant Leela's Hurdles - S5-E7
Factual error: When Professor Farnsworth visits the Bubbling Geezer to receive youthasizing treatment, the trained professional Heather says "botulism toxin tightens and tones facial muscles." Botulism is the actual poisoning, not the toxin. Botulinum toxin causes muscle paralysis which weakens the muscle, not tightening and toning of the muscles.
Answer: You are thinking about episode 20 of series 2 - "Anthology of Interest I". She technically never kills anyone, but in the episode she ask a "What if machine" (one of the Professor's inventions) what would happen if she was more impulsive. The machine then shows the more impulsive Leela killing off the Professor to get the money from his will and thereafter killing Hermes, Bender, Scruffy, Cubert, Nibler, Amy and Zoidberg to cover it up. Finally she does something really impulsive with Fry.
Andreas[DK]