When Maggie kills the Simpson family's enemies, she has an eye painting similar to Alex from the movie A Clockwork Orange.
Frank Grimes references to the 600th episode mark saying "In hell they make you watch them all in a row". This is possibly a reference to a 13 day marathon that happened on FXX to celebrate the milestone, where all 600 episodes of The Simpsons were aired in a row.
The "Planet of the Couches" couch gag is an obvious parody of Planet of the Apes.
The name of the segment is a reference to the movie series Die Hard.
Mr. Burns reenacts one of the dance scenes from the movie Flashdance.
Lisa says that after the river dried a drought of Chicago Cubs sized proportions hit Springfield, referencing the drought of World series wins for the Cubs, although they did win the World Series in 2016.
"BFF R.I P." is two acronyms for "Best Friends Forever" and "Rest In Peace".
The segment itself is probably a parody of the movie Lights Out.
Dan Vebber's nickname is "H.P Lovebbercraft", a reference to H.P Lovecraft.
Drew Carey's Halloween nickname is "Boo Scary from The Fright is Right!" which refers to his status as the host for The Price is Right.
When the family sits on the couch, Homer's hand is in front of Marge, not behind her.
The order of cars going to Mr. Burns' reservoir changes between scenes.
Also, the kid on top of Apu's vehicle (either Sashi or Pria) is yellow with blonde hair in one of the shots.
Wendell was not near Nelson when he helps surround Lisa, but his body is shown on Nelson's sword.
There was no reason why Lisa was blamed for the murder of Sherri and Terri. It happened right besides Janey's funeral and people probably saw that Lisa did not push the tombstone as she was talking with them.
When Lisa mounts on the motorbike, her right arm goes in the front of the bike's headlights.
The shelf at Moe's tavern was full of bottles, but on the next scene, it is full of empty beer mugs.
Kearney stated that all the bullies were all thirteen.
It was previously established he is in his twenties while Jimbo was eighteen and Dolph was thirteen.