When you think about the lyrics, “Santa Claus is Coming to Town” is actually a pretty creepy song. Still, it isn’t exactly giving children nightmares like “O Tannenbaum.” Thank you, Germans.
For those confused, Rick’s line is a reference to the Saw film franchise.
SINGING: He knows if you've been bad or good, So be good for goodness sake!
SINGING: O! You better watch out!
RICK: Santa's the Jigsaw killer!