Homer and Bart participate in a Robot Wars-style robotic combat game show with Homer disguised as a robot in order to help his son, as building an actual robot was beyond him. Meanwhile, Snowball II dies and Lisa goes through a string of replacement Snowballs.
- Attack Its Weak Point: Played With. Bart said Professor Frink's robot had one of these, only to see Frink upgrade it to the robot's strongest part.
- Call-Back: The montage of Homer and Bart winning their fights is set to "Watching Scotty Grow". When Homer is losing the final bout, he deliriously sings a few lines of the song.
- Cats Have Nine Lives: Mentioned during Snowball II's funeral. Lisa wrote her a poem.Lisa: I wrote this poem for you. It's called "Cat Math".
Four paws, plus one tail, plus nine lives equals one special cat.
One special cat minus nine lives equals one sad little girl.
- Chronic Pet Killer: After Snowball II dies, all other cats Lisa purchases kill themselves in rapid succession in a barrage of accidents (and one apparent suicide), none of them even making it to a single day. The animal shelter eventually refuses to sell Lisa any more cats, telling her that they will be a whole lot safer by staying in death row.
- Combat Pragmatism:
- Homer's advantage against other robots is that he can fight dirty (smashing the controller of Jessica Lovejoy's robot, for instance).
- Ralph Wiggum's robot uses an actual handgun as a weapon. Homer somehow manages to dodge the gunshots (though a couple graze his arms), and he takes the gun away from Ralph's bot, emptying the clip on it.
- Discontinuity Nod: Lisa sarcastically calling Skinner "Principal Tamzarian" when Skinner tells her that it's dumb to just call another cat "Snowball II" to save on buying a new bowl. Skinner leaves her alone (and the torture penalty for doing that? Never mentioned).
- Disproportionate Retribution: Homer has a nightmare where he wins an Oscar and a robot kills him for making a speech that lasts longer than 30 seconds.
- I, Noun: The title is "I, (Annoyed Grunt) Bot" or "I, D'oh-Bot".
- Loophole Abuse: Averted. When Homer was announced as a robot fight champion despite not being a robot, the one announcing Homer dared everyone to state any rule prohibiting humans from being robots. He was then shown Rule Number One.
- Meet My Good Friends "Lefty" and "Righty": During Bart and Homer's first robot fight, Moe is seen in the audience, lamenting that he's seemingly the only adult sitting among a crowd of teenagers. The Squeaky-Voiced Teen, who happens to be sitting next to him, asks Moe if he has his children with him, prompting Moe to hold up his fists and introduce them as his two kids, "Screw" and "You".
- Misery Poker: When in bed Marge is worried that she just doesn't know what to do with Lisa being depressed over losing many cats. Homer simply shows her a large metal shrapnel and says he just removed it from his leg. Marge kind of forgets her problem and just helps Homer removing more shards of metal scraps with a magnet.
- Non-Protagonist Resolver: Lisa's ready to give up on getting a new cat until an angelic figure approaches the Simpson home... and it's the Crazy Cat Lady, who flings a cat to Lisa.
- The Pollyanna: Ol' Gill is glad he crashed his car because he'll get a check from insurance.Gil: I'll be eating food tonight.
- Pet the Dog: The Crazy Cat Lady giving a very depressed Lisa one of her beloved cats (well, more like tossing it to her, and who knows what she was thinking when all she says is gibberish).
- Removed Achilles' Heel: Much to Bart's (and Homer's) fear, they discover that the Frinks have reinforced their robot's sole weak spot with so much extra armor that it's now its toughest spot. For further irony, Bart discovers it just as he's explaining his battle plan, making him Instantly Proven Wrong.
- Reset Button: Played with. Because the cat that the Crazy Cat Lady gave her looks like the recently-deceased Snowball II (and because she doesn't wants to go through the hassle of buying a new bowl), Lisa decides to call her new cat "Snowball II". It's played with because Principal Tamzarian then points out that she's pressing the Button out of laziness.
- Self-Deprecation: Most of the cast and crew of the Simpsons considers "The Principal and the Pauper" note to be an Old Shame, and Al Jean is no exception. He hated the episode so much, when he returned as executive producer he retconned the episode every chance he got. This episode is a rare exception, but Lisa calling Skinner "Principal Tamzarian" after he calls her out on naming her new cat who looks exactly like her old cat "Snowball II" is a nod to the blatant Reset Button at the end of "Principal".
- Frink's robot goes by the name of Chassis Clay, aka Killhammed Aleee and looks like ED-209.
- The robot that is crushed and turned into a trophy by Frink's robot resembles that of of an Endoskeleton. Videotapes labeled "Killhammed Aleee vs. Sugar Ray Leonard" and "Killhammed Aleee vs. Bender can be seen in the following scene.
- Snap Back: Lampshaded. At the end of the subplot, Lisa christened her final cat "Snowball II". When Principal Skinner called her out on this, Lisa says "I guess it is, Principal Tamzarian."
- Straw Loser: One more point for Gil Gunderson. The man crashes his car because of Homer's antics, the wreck's on fire, he's on fire, and yet he's still dancing a jig because:Gil: Oh, Ol' Gil's gonna collect big from insurance. I'll be eating food tonight!
- Survivor's Guilt: After Snowball II's death, Marge tries to console Lisa by saying she coped with the loss of her pet guinea pig, only to break down as she says the following:Marge: Oh, Cinnamon! It should've been me who chewed through that extension cord.
- Super-Powered Robot Meter Maids: Frink's robot, that would probably see better use in an active war zone than fighting kid's robots, has a mode where it transforms into a couch with integral speakers and an arm that provides beverages.
- Take That!: When Chief Wiggum disguises his car as a pizza car, he uses a Domino's Pizza logo to be sure nobody will want any pizzas from him. Sky 1's airing of the episode in the UK removes this scene, mainly due to the fact that Domino's sponsored the show for 10 years, and having a scene which insults the sponsor would have likely caused trouble.
- There Is No Kill Like Overkill: Frink's robot, "Killhammed Aleee", is a copycat of the ED-209 with the firepower to match. The Frinks use it to participate in (or rather curb-stomp their way through) kids' garage robot gladiator competitions.
- Three Laws-Compliant: Frinks robot, luckily for Homer.
- Uncatty Resemblance: One of the cats Lisa gets, named "Coltrane", looks more like a kitten version of Bart and turns out to have the same hatred for Jazz that Bart has, deciding to jump out the window of Lisa's second-floor room to its death rather than hear more than two seconds of John Coltrane's music.
- Unrobotic Reveal: In-universe.Sideshow Mel: That robot has given birth to a man!
- What Measure Is a Non-Human?: "Can robots feel pain? If so, we are horrible, horrible people!"