A Glitch in the Matrix: Ben's first clue that something was up was how the Omnitrix acted funny, like it was being operated by an unseen force.
Call-Back: Lieutenant Steel claims Max and Gwen are actually Limax working for Vilgax.
Comedic Underwear Exposure: In a flashback, Ben's Sumo Slammer boxers are exposed when his pants fall down in front of a bunch of older schoolgirls who laugh at him.
Faux Horrific: For Ben, the most nightmarish setting he could imagine is... School!
Foreshadowing: There are some clues that hint that Ben is in a Lotus-Eater Machine, with some clues even being pointed out by the Pop-Up Trivia in the enhanced episode.
Max actually serves normal human food for breakfast instead of the usual alien food.
Max and Gwen seem to be a lot stronger than usual.
Ben is actually able to take on Vilgax quite easily, when the real Vilgax is actually The Juggernaut that Ben would normally have trouble fighting against.
Jerkass: The schoolgirls who laughed when they saw Ben's underwear.
Hoist by His Own Petard: Enoch is trapped in his own Dream Machine and is left there for several years by the Forever King.
"Kick Me" Prank: Ben as XLR8 puts a "kick me" sign on Enoch's back.
Lotus-Eater Machine: The Forever Knights put Ben in this in order to keep him distracted long enough to remove the Omnitrix from him. Enoch winds up trapped in this machine himself at the end.
Once More, with Clarity: The first act of the episode is Ben having the titular "Perfect Day". In the second act, when the perfect day turns into a nightmare, we have a flashback of Ben having a version of the day he was having. Only this time, it was actually the worst day.
Out-of-Character Alert: One of the things that convinces Ben that the real Gwen and Max are telling the truth is when the former points out that Vilgax would actually try to take the Omnitrix from Ben first before sending him to the Null Void.
