Continuity mistake: The "Cartridge Robot" never takes the "Introduction" tape out of his slot, but in the wider shot it's suddenly vanished.
Continuity mistake: When Bender and the other obsolete robots are watching a snail crawl across the beach, the snail is shown to be in the center of the screen with the robots standing around. Cut to Bender inserting a CD in his mouth, it then goes back to showing the original angle, but the snail has suddenly disappeared, and not enough time has passed for it to have crawled all the way out of the shot. (00:12:10)
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]