Marshall uses cards from the board game "Clue" in order to explain the relationship of Zoe and Ted to his mother and brother. Throughout the episode, the characters appear in clothes colored according to the characters from "Clue" which Marshall uses. Ted is Professor Plum, Zoe is Mrs. White, Honey is Miss Scarlet, Barney is The Reverend Green and Marshall refers to the Captain as Colonel Mustard.
When Barney passes Zoey on the street, he's carrying a silver briefcase. However, if you look closely you will notice that he is actually handcuffed to the briefcase. The episode never explains why.
Honey (Katy Perry) mentions at the beginning of the episode that she is going to be on 'Lost' (2004-2010). Five episodes earlier Jorge Garcia, who plays a central character on 'Lost', appeared as Steve The Blitz on this show.
Katy Perry (Honey) is the fourth star from Smurfs (2011) that has appeared in How I Met Your Mother. Neil Patrick Harris (Barney) starred in it as well as: Jayma Mays (Coat Check Girl in season 1 episode 5, Okay Awesome) and Tim Gunn (in season 5 episode 12, Girls versus Suits).