When Homer realizes that he can't live in a fantasy, he recalls the activities he will never be able to do if nothing ever changes. This is ironic, however, because since they are on a floating timeline, nothing will change either way.
This is the only episode of Season 25, and one of the very few episodes overall that does not have neither the Chalkboard Gag nor the Couch Gag in the Opening Sequence.
The episode may have ether been in celebration of the new Simpsons line of LEGO or to celebrate the 550th episode.
The overall plotline of this episode is a parody of The LEGO Movie. This is confirmed when Lisa makes a meta-reference saying that it has been done before. Emmet and Wyldstyle from The LEGO Movie are then shown in the background.
Krusty and Scratchy figures are seen on the shelf in the Android's Dungeon, as well as a poster of Radioactive Fig (a parody of Radioactive Man) and multiple books and films by Philip K. Brick (a play on Philip K. Dick) including Do Minifigures Dream of Plastic Sheep? (Do Androids Dream of Electric Sheep?), Block Runner (Blade Runner), A Scanner Brickly (A Scanner Darkly), Sort My Pieces, the Policefig Said(Flow My Tears, the Policeman Said), Ubrick (Ubik), and Beyond Lies the Stub (Beyond Lies the Wub).
There is a secondary plotline homage/parody that encompasses this episode as indicated by another book on the shelf which is The Three Brickmata of Palmer Elbrick (The Three Stigmata of Palmer Eldritch). In this episode, Homer is similarly transported to an alternate reality (like in the said novel) by touching the box of "Perky Patty's Princess Shop". This is the main theme that runs through almost all of Philip K. Dick's science fiction; What is Reality and How Do We Know?
Fictional Homer awakens one day as his normal (LEGO) self, only to stumble into another dimension that we the viewers recognize as his normal cartoon self, which of course is not real. This paradoxical and funny situation is typical of PKD's writing and was the inspiration for The Simpsons writers. When Jeffery Albertson points to the sign on his wall, it reads, NO OUTSIDE REALITIES.
Jeffery Albertson turning his face from good to bad is a reference to The LEGO Movie where the character Bad Cop/Good Cop can switch his face between either good or evil emotions. It is also a reference to the two-sided heads in many LEGO sets.
The scene where Homer touches the castle box and has the visions is a reference to when Emmet touched the piece of resistance in The LEGO Movie.
The duck seen on the stained glass of the LEGO First Church of Springfield is LEGO's wooden duck released in 1935, the first toy ever released by the company.
The ninjas have the same headpiece as the 2011 Lego Ninjago heads.
My Little Pony: Friendship is Magic is referenced when Jeffery Albertson thinks that Homer is an AMFOP (Adult Male Fan of Princesses) which is a reference to the fans of My Little Pony called "Bronies" and is perhaps a reference to AFOL's (Adult Fans of Lego).
Survival Games is a parody of The Hunger Games.
When encountering Jeffery Albertson, Bart says "You're going back from where you came... Denmark.", referencing the fact that Legos originated in Denmark.
The Gracie Films logo has Marge's shushing instead of the Shush Lady.
Homer's lines, "Kiss my flat plastic butt" is possibly a reference to Bender's catchphrase in Futurama: "Bite my shiny metal ass".
Everyone in the Simpson family are seen both in LEGO form (in the LEGO segments) and inthe regular form (seen outside of the LEGO segments), except for Maggie and Bart, who are only seen in Lego form.
The heads of the characters in this episode resemble the standard Lego minifigure head, but the real Simpsons Lego minifigures have specifically made head sculpts.
In this episode, Lisa claims that she had never hung out with older kids. However, she previously did in Little Girl in the Big Ten, it's possible this may happen right before
When Lisa constructs her "Perky Patty's Princess Shop", the walls go diagonally. No LEGO blocks go that way.
While Bart is reconstructing the twelve schools, there is a pink house behind him that changes in distance and appears on the other side of the road. This changes and then disappears when all twelve schools are completely rebuilt.
When Nelson is in pieces, he is seen with his normal legs, but when Skinner reassembles him, his legs are short.