Random Trivia For This Title:
- Actress Stephanie Beatriz (Sweet Mayhem) has a signature small scar on her right eyebrow which was caused by, coincidentally enough, tripping on a piece of LEGO when she was 10 years old.
- A comment is made about Marvel "not returning our calls." Characters from the Marvel Universe are conspicuously absent from the Lego movies, due to rights issues with Disney. Characters from the [Star Wars] universe (also owned by Disney) appeared in The Lego Movie (2014), but not in this sequel.
- During the "Gotham City Guys" song, references are made to every actor who has played Batman in live action movies since 1966: Christian Bale, Michael Keaton, Ben Affleck, George Clooney, Val Kilmer and Adam West.
- When the Justice League go to fight the alien invaders, someone asks where Batman is, to which Superman replies that he's off on a solo adventure - presumably, the events of 'The Lego Batman Movie'.
- When Mom steps on a brick, she comments that the level of pain is close to that of childbirth. Obviously, she's joking, but studies have shown that the pain of stepping on Lego bricks is actually higher than that of walking across hot coals or broken glass.
- Richard Ayoade (Ice Cream Cone) and Noel Fielding (Balthazar) are longtime friends and frequent collaborators, having worked together on '[The Mighty Boosh'] and '[The IT Crowd'], as well as being frequent teammates on '[The Big Fat Quiz of the Year.']
- Two of the raptors' names are Ripley and Connor. They are named after the two sci-fi heroes Ellen Ripley, from the [Alien franchise], and John Connor, from the [Terminator franchise].
- Rob Schrab was going to make this film his feature directorial debut, until he was replaced by Mike Mitchell.
- When Emmet makes his spaceship to rescue his friends, he tells planty to buckle up. This is a reference to "Guardians of the Galaxy", when Star-Lord (Chris Pratt) tells Groot (Vin Diesel) to buckle up.
- Rex Dangervest's comments about having a chiseled jawline hiding under baby fat are a reference to the physical changes voice actor Chris Pratt went through preparing for his role in Guardians of the Galaxy (2014).
- Rex Dangervest (Chris Pratt), the main antagonist, says he is a "galaxy defending archaeologist, cowboy, and raptor trainer". To which Emmet (also Chris Pratt) is confused. These are allusions to Chris Pratt's live-action past roles as Peter Quill/Star-Lord in Guardians of the Galaxy (2014), Josh Farady in The Magnificent Seven (2016), and Owen Grady in Jurassic World (2015).
- When Rex, Emmet and the raptors arrive at the Sistar System, the scene where they leave the ship is a remake of the scene from Aliens (1986) where the crew rolls out on LV-426 with the same motion detector