In this year's Halloween special, Marge accidentally kills Ned Flanders, Bart and Lisa become superheroes, and Homer causes a technological apocalypse when his work computer is the only one that isn't [[MillenniumBug [=Y2K=]]]-compliant.

!!!"[=Tropehouse=] Of Horror X":

* AdamWesting: Tom Arnold, who admits he's a lousy celebrity.
* KilledOffscreen: Unusually, it's Homer who was killed offscreen by a werewolf [[spoiler:Flanders eating him]]
* IAmNotSpock: Lucy Lawless grabs Bart and Lisa and flies them back home. On the way, Lisa notes that Xena can't fly. Lucy reminds them she's not Xena. Apparently Lucy Lawless can fly normally.
* OhCrap: Oh no, Rosie O'Donnell!
* OminousFog
* SadisticChoice: When the world ended, there was a rocket sending the smartest people to Mars. Lisa got to go but wouldn't be allowed to take both of her parents. [[SubvertedTrope She quickly chose her mother as soon as the soldier mentioned the restriction]].
* ScrewThisImOuttaHere: In "Life's a Glitch", Bart informs Homer that, even though they might be on a rocket with Rosie O'Donnell and Pauly Shore, amongst others, they will be dead in 5 minutes (as they will crash into the sun). Homer is quick to react to this news.
--> "NOT FAST ENOUGH!"
--> ''(Presses button and ejects himself and Bart into space)''
* SuperheroEpisode: [[RubberMan Stretch Dude]] and [[SuperStrength Clobber Girl]] protect Lucy Lawless from The Collector.
* TakeThat: The rocket sent on a collision course to the sun with the apparent purpose of getting rid of the worst/most useless people on Earth. Which include Ross Perot, UsefulNotes/DanQuayle, Tonya Harding, Al Sharpton, Music/CourtneyLove, Creator/SpikeLee, Tom Arnold, Pauly Shore, Rosie O'Donnell and Dr. Laura.
* TotallyNotAWerewolf: [[spoiler:Ned Flanders!]]
* AWizardDidIt: This episode is the [[TropeNamers Trope Namer]], which comes from a line from Creator/LucyLawless (The actor who plays the titular character of ''Series/XenaWarriorPrincess'') as a quick way to answer fans complicated questions.
* YourHeadAsplode: In "Life's a Glitch, Then You Die", Homer and Bart realize they're on a rocket that's heading into the sun with various washed-up and overall terrible celebrities. Rather than spend another five minutes with Rosie O'Donnell and Tom Arnold, they eject themselves into space, where their heads swell up as they give a blissful sigh of relief and then pop [[spoiler: offscreen]].