Ratings: 11.81 million
This episode marks the first appearance of John Ross Bowie as Dr. Barry Kripke, the badly lisping nemesis of Sheldon. Kripke would continue as a recurring character in future seasons of the show.
The title refers to the killer robots that the guys and Kripke build and fight.
This is the first time that Penny goes to Howard's house and meets Mrs. Wolowitz.