Tropes
- Animalistic Abomination: The Demon Cat, which has a cat shaped tongue and left limbs that are missing a section connecting to the body.
- Bad Samaritan: The Guardian Angel rescues Finn from the cat monster, heals his wounds, and mends his clothes... then she announces her intention to cook and eat him.
- Big Damn Heroes: Princess Bubblegum swoops in to save Finn and Jake from a seemingly hopeless situation.
- Chest Monster: Finn encounters a mimic that vomits treasure when awakened.
- Does This Remind You of Anything?: When trying to get the key from the gelatinous cube, he grunts that the cube "[shouldn't] flaunt it if you're not gonna give it up".
- Furry Reminder: During one of his challenges, Jake is shown being distracted by a goblin with a laser pointer.
- Gelatinous Encasement: Finn runs into a jelly cube trying to explore the dungeon that the episode is named after. He tries his best to grab the key lodged inside of it, and he does not succeed.
- Graceful Loser: When Jake catches up to Finn after following him into the dungeon, he proceeds to help Finn win his bet made against him of getting the Crystal Eye and getting out in 11 minutes, which Finn lampshades the absurdity of.
- I'm a Humanitarian: It turns out the "guardian angel" wants to cook and eat Finn.
- Leaning on the Fourth Wall: Finn brags that he'll be in and out of the Dungeon of the Crystal Eye in "eleven minutes" (the typical length of an episode of Adventure Time).
- Left the Background Music On: The jaunty xylophone music that plays when Finn and Jake escape the giant cage turns out to have been played by the guardian angel.
- Light Is Not Good: The guardian angel is clothed in white and has a brightly-glowing body, but her true form is a hideous skull-faced monster and she tries to eat Finn and Jake.
- Miracle-Gro Monster: Bucket Knight originally appears small, but by dousing himself with water, he grows gigantic and gives Finn a major beatdown.
- Nightmare Face: The angel's Jump Scare face.
- No-Holds-Barred Beatdown: The Bucket Knight gives Finn a rather brutal one.
- Our Angels Are Different: This one has a Nightmare Face and is a man eater.
- Plot Tailored to the Party: Parodied; Finn encounters challenges that would have been easy for Jake, but are hard for him. When he goes in after Finn, Jake encounters challenges that would have been easy for his human buddy.
- Red Eyes, Take Warning: After Finn punches the Demon Cat and he yells "Now you die!", his eyes begin to turn red before attempting to maul the human boy.
- Save the Princess: Inverted; towards the end of the episode, the heroes are stuck in a bad situation and it's up to the princess to rescue them.
- Shout-Out The Demon Cat behaves similarly to another cunning big cat.
- Unhand Them, Villain!: When the guardian angel reveals her true form, Finn tells her to put him down and the angel does what he asked... dropping him into a cage/stew pot hanging over a cooking fire.Finn: Put me down, lady!
Guardian Angel: As you wish. - Unusual Euphemism: When offering Finn a ride, Jake wiggles his butt and tells Finn to "hop on my powdered doughnut."
- [Verb] This!: When the demon cat threatens to unzip Finn's skin and wear it like a coat, Finn retorts "Unzip this!" and taunts him with an armpit fart.
- What Kind of Lame Power Is Heart, Anyway?: The cat has the power to be almost right about everything, which leads him to call Finn "Frank" and "Jim".
