John Goodman guest stars in this episode as Robot Santa; however, he was unavailable to reprise the role in the later episode "A Tale of Two Santas" so he was replaced by John DiMaggio. Conan O'Brien makes an appearance as his own head in a jar. In order to make a visual joke that O'Brien has a large head in real life the head was drawn sticking out the top of the jar. This choice caused many difficulties for the animators because it did not work with the animation layers typically used for other head-in-a-jar characters. Frank Welker voices Fry's parrot and created the annoying squawk used. The initial squawk he made was considered to be annoying but according to Cohen they had him continue to make the squawk more annoying until he had done nearly a hundred different parrot squawks.