Original airdate: September 28, 1991
Big Mouth, Kootie Pie and King Koopa bring the cave people to Neon Castle for a circus, intending to feed them to dinosaurs.
Tropes:
- Aside Comment: While advertising for his circus, King Koopa tells the audience, "This is easier than talking Kootie Pie into a shopping spree!"
- Bland-Name Product: The Koopaling Bros. Circus is this to the Ringling Bros. and Barnum & Bailey Circus.
- Circus Episode: King Koopa invites the cave people to see his staged circus for free. The Mario Bros. realize too late that it's a ruse, and they have to save the cave people from being eaten by dinosaurs. At the end, the Mario Bros. and Princess Toadstool host their own circus for the cave people.
- Malicious Misnaming: When fighting the Mechkoopas, Mario refers to them as "Mashed Koopas".
- Mass "Oh, Crap!": Mario, Luigi and the cave people when they realize that the circus was a trap after all.
- Mythology Gag: Near the end of the episode, just as Mario is about to rescue Luigi, Yoshi, and the cave people, a battle reminiscent of the final battle from the game the show is based on is shown, complete with Koopa using similar attack patterns, and Mario defeating Koopa by tossing a Mechkoopa at him.
- Oh, Crap!:
- Mario when one of the Dino-Rhinos is about to eat him in the cage.
- Kootie Pie and Big Mouth just before the circus tent falls on them.
- Koopa at the end of the episode when Mario sends the Mechkoopa into his Koopa Clown Car so he can rescue Toadstool.
- Paper-Thin Disguise: Mario and the cave people don't realize the clowns in King Koopa's circus are actually Rexes until one of their noses falls off.
- Pie in the Face: The circus performers torture ringmaster Big Mouth, hitting him with a pie at one point. Then, a pie-throwing machine is rolled out with the ammo hitting Rexes disguised as clowns and cave people in the audience. Yoshi saves the Mario Bros. from punishment by eating any pies that are launched in their direction.
- Pragmatic Adaptation: This episode explains why someone as mean and nasty as King Koopa would have a helicopter with a clown face.
- Repulsive Ringmaster: Big Mouth plays one in the Koopas' circus.
- Shout-Out: King Koopa paraphrases The Twilight Zone (1959)'s Opening Narration while barking for his circus.
- The Voiceless: Kootie Pie has no lines in this episode, aside from laughing at the clowns when they terrorize Big Mouth, or screaming when the circus tent comes crashing down on her.
- With Cat Like Tread: Big Mouth yells at Kootie Pie to keep quiet while they set up posters. Kootie Pie sticks a poster on his mouth which muffles his voice.
