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2021 Golden Stake Nomination
SilverStake This article was nominated in the 2021 Golden Stake Awards. It was nominated for the following category: Funniest Episode
However, it didn't win for this category

"Mystery Dungeon" is the eighth episode in the fifth season of Adventure Time. It's the one hundred and twelfth episode overall.


An unlikely group consisting of Ice King, Neptr, Tree Trunks, Shelby and Lemongrab must work together to escape a dungeon they mysteriously awaken in.


The episode starts out with Ice King, Neptr, Tree Trunks, Shelby, and Lemongrab awakening in a dungeon. Lemongrab starts to say cryptic words, leaving the others in confusion. Tree Trunks asks Lemongrab what he just said, and he says he was reading the words on the wall. Then, all the characters start reading the wall, which says:

Awake, avast, hold tight your buns, if buns you do hold dear

For time has come to wake and run and not give way to fear

Beyond this room are a thousand rooms, outside of them still more

Behind each door, on every floor, danger, danger, ever more.

Stranger, hark! The traps galore may kill you whilst you do explore

To free yourself from this tomb, and nevermore re-enter

Find the room amidst the rooms that lies exactly center.

The walls then start to come in on everyone. In panic, Tree Trunks opens a door, not knowing that it leads to a deadly drop deep into the dungeon. Neptr saves her with one of his "mods" (an extendable arm). Through all the confusion and panic, Lemongrab notices the lock for the trapdoor on which they were standing and proceeds to unlock it.

Falling to the next room, the Ice King quickly notices its lack of doors. Frustrated, Lemongrab asks how the Ice King tastes and he says he does not know. Lemongrab then gets enraged and screams, "MILD OR SPICY?!" Ice King remembers himself kissing his hand, and he says, "Kinda lonely." Lemongrab then demands that the Ice King "make [himself] into food." Neptr quickly breaks up the fight, pointing out that he found an oven and baking supplies. Tree Trunks says she can bake an apple pie for them. Minutes later the pie is done, to the delight of the hungry group. The pie's aroma lures a giant rat out of a secret door, which quickly eats the pie. Furious, Lemongrab punches the giant rat; and starts eating the pie out of its mouth (to the disgust of the others). The Ice King then points out that the rat showed them the room door.

They crawl towards the next room, which has a pool of steaming water with a giant fish tied to a plug on the floor. Ice King tries to fly them over, but the steam is nullifying his powers. He then tries to freeze the water, but the steam quickly cancels the magic before it even leaves his hand. Giving up, he tells the others they can have his corpse for food, to which Lemongrab wholly assents. Shelby thinks of an idea, which involves using Tree Trunks as bait. The Ice King then struggles to reel the fish out of the water with Neptr's help, unplugging the hole in the process. Tree Trunks frees herself out of its stomach with the dagger that she was biting down on, and they proceed to the next room.

Upon entering, they quickly encounter a giant three eyed tentacled monster. The group would have been overwhelmed had it not been for Lemongrab's juice being squeezed out by the monster (which seems to be its weakness). The encounter leaves Lemongrab literally drained. Tree Trunks then inflates him back to normal, oddly restoring his "vital juices" in the process. The group then enthusiastically runs to the next room, unaware of the fact that the bridge is broken. Using his torn robe as a makeshift parachute, the Ice King flies them to safety and in front of the door to the central room.

Neptr then explains that the door is secured by an esoteric encryption system. The Ice King confidently replies that he can easily "hack the mainframe" (mistaking Neptr for BMO). Neptr confusedly states that he throws pies. Ice King then angrily states that he grabbed the wrong robot, which makes Tree Trunks and Shelby realize that something is wrong. The Ice King confesses, explaining that he brought them to the dungeon due to their unique qualities—qualities which enabled them to get past the various tests of the dungeon. The Ice King is ready to give up, frustrated that he accidentally brought Neptr along instead of BMO. Still eager to please his "father," Neptr throws a pie at the door, breaking and opening it in the process.

It is then revealed that the door contains the Ancient Sleeping Magi of Life Giving. The Ice King explains that anything that goes through its flames comes to life. Showing the others his "Fionna and Cake" fanfiction, the Ice King reveals that he intends to bring the characters of his fan fiction to life. A dismayed Lemongrab attacks the Ice King with his sound sword, which strikes the Ice King, but not before he throws his fan fiction towards the flames. However, the flames can only bring the book to life, not what is written on it. A disappointed Ice King is quick to blame and insult the Magi, calling him a "bum" and telling him to "get out of [his] face."

Finn and Jake are then seen on the grasslands, following the smell of the pie that Tree Trunks made earlier. The Magi then flies off behind an unaware Finn and Jake, followed by the rest while Lemongrab leaves saying goodbye and don’t follow him. A depressed Ice King sits down nearby, approached by Neptr. Neptr comforts him, saying that his characters can always be real in "the garden of his mind." Delighted, the Ice King imagines talking to Fionna, unaware that it is actually Neptr talking. Finn, Jake, and Shelby watch from a distance wondering who in the world is sadder than the Ice King, to which Shelby replies, "Me, watching this."


Major characters[]

Minor characters[]




  • It is revealed in this episode that the Ice King loses his powers in very hot and humid conditions.
  • It is revealed that the Ice King almost completely does not remember Neptr, which is a stark comparison to the events in "What is Life?" where the Ice King thought of Neptr as his own son.
  • Finn and Jake can be seen in the hieroglyphics of the title card.
  • It is revealed that when Lemongrab is squeezed, lemon juice comes out of him, which is like Lemongrab's "essence."
    • He is also shown to be able to stretch and extend his jaw, revealing a multitude of razor-sharp teeth.
  • This is the first episode featuring Lemongrab where he doesn't say the name of the episode's title. He's done this in season 3’s "Too Young", season 4's "You Made Me", this season's "All Your Fault" and "Too Old".
  • This is the first time the gender-swapped version of Marceline, Marshall Lee, is mentioned by name in the series.
  • Tree Trunks calls the others incorrectly: She calls Ice King "Ice Cream" and Lemongrab "Lemoncarb." She also refers to Neptr as "Nectar." Shelby's name is the only one that she appears to say correctly.
  • It is revealed that Lemongrab has a great memory, a trait that would come into play again during the episode "All Your Fault."
  • Although Fionna appears and speaks in Ice King's Imagination Zone, it is Neptr's (Andy Milonakis) voice and not Fionna's (Madeleine Martin) that is heard.
  • Tree Trunks knew that there were two Lemongrabs because she said to Shelby, "...and one of the Lemoncarbs."
  • When the book comes to life, its shoes are similar to that of Finn's.
  • This is the first appearance of the Ancient Sleeping Magi of Life Giving.
  • It is ironic that the Ice King attempts and fails to bring the world of Fionna and Cake to life, given that "Prismo the Wishmaster" would later reveal that their world is real and planted into the Ice King's mind by its true creator, Prismo.

Episode connections[]

  • Lemongrab is shown to still posses the ability to rotate his head nearly a full 360 degrees, as he did in "You Made Me" when addressing the Pup Gang.
    • His question to Ice King, "MILD OR SPICY?!" could refer to the episode "Too Young" when Finn and Princess Bubblegum spiced up nearly everything he ate to get him to leave the Candy Kingdom.
  • This episode connects to "What is Life?" through the reunion of Ice King and his "son" Neptr; it further is connected by Neptr reminding his dad of the Imagination Zone when he is desperate to see Fionna come to life.
  • The title card music of "Hug Wolf" can be heard when Neptr was saving Tree Trunks from falling.
  • Lemongrab still does not seem to know where food comes from, as he first mentioned in "Too Young."

Cultural references[]

  • Of the images that appear on the computer mainframe, some recognizable images include: The Eye of Horus, a man with a sword in his abdomen, a hand grabbing a key, and an hourglass.
  • The voice and the laugh of Ice King's animated book is similar to that of Mickey Mouse.
  • The scene when Lemongrab shows his teeth is similar to Jennifer showing her teeth when possessed in "Jennifer's Body".
  • When consoling the Ice King, Neptr refers to "the garden of your mind", the idea first publicized by Mister Rogers of Mister Rogers' Neighborhood, who said, "you can grow ideas in the garden of your mind".
  • The episode, according to Jesse Moynihan, was inspired by the Cube film series, in which a group of people wake up in a maze not knowing how they got there. Every room of the maze has a trap and is connected to other rooms, and the group must work together to escape.[1]
  • On the Ice King's book is the word "omnibus", which means "for everyone" in Latin, and it's a sub-title used in books that contain reprints of the full number of works by one author, implying the book that Ice King made contained the entire Fionna and Cake's "fictional universe" (which seems conflictual with the huge number of books seen in the ending of the episode "Bad Little Boy").
  • The episode may be influenced by the Star Trek: The Next Generation episode Allegiance, Where Captain Picard and three other aliens are mysteriously imprisoned and tested based on their unique behaviors and attributes.
  • In the scene where it was too hot for Ice King's powers, the black fixtures on the wall resemble the wind fans inside the Shadow Temple from Legend of Zelda: Ocarina of Time. Additionally, the water draining after the sea monster's defeat is similar to Morpha's defeat in the Water Temple, from the same game.
    • The room being too hot may also be a reference to the Fire Temple - Link couldn't even enter without heat resistant clothing.

Storyline analysis[]

  • At the end, the dungeon is revealed to be under a location very similar to the hills featured on "All the Little People", with even the same sunset design and colors. Furthermore, in other to get out of the dungeon, one must lift the grass and dirt, similarly to how the Magic Man did the same in the mentioned episode. All this indicates that, in order to give life to the Little People, Magic Man used the Ancient Sleeping Magi of Life Giving's magic.

Production notes[]

  • This episode aired early in Australia, and some parts were censored.
    • Oddly, this is one of the only episodes to be censored in the United Kingdom, while some episodes, such as "Freak City" remain uncensored.


  • Lemongrab was able to read the wall without his glasses, although this could mean that he is farsighted and only needs his glasses to see things that are close to his face. 
  • There was no puddle of blood near the pile of skulls when the giant spiked gate opened itself. It appeared when Lemongrab was lying down on the floor and a puddle of blood that was around a spike is gone. Also, when Tree Trunks is helping Lemongrab recover some juice, there are some skulls stacked up against a spike that were not there before and all the blood on the spike is gone.



This episode was censored in some countries. See Censorship of Adventure Time for more information.


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