Adventure Time / Tropes A to C

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  • Abandoned Catchphrase: Adventure Time has a bunch of these from the first season:
  • Absurdly Sharp Blade: Finn's second and third swords. The second sword can sink into wood like hot butter, while the third is a family heirloom crafted from demon blood, and can cut through diamond. His fourth sword, the Grass Blade, is sharp and precise enough to cut the image of his face into something as small as a price tag. As well as being sharp enough to destroy fear itself (by slaying the Fear Feaster at the end of "Billy's Bucket List"
  • Accidental Misnaming: Tree Trunks keeps referring to Lemongrab as "Lemon Carb". This is not malicious, but more an indication of her borderline senility.
  • Action Girl:
    • Fionna, appropriately enough, considering that she's a gender-flipped version of Finn, a professional adventurer.
    • Princess Bubblegum also proves she's capable of handling business herself when Finn and Jake are abducted. One gets the distinct impression that she could handle most of the threats she throws Finn and Jake at herself if she wasn't so busy administrating the kingdom and doing mad candy science.
  • Actual Pacifist: Simultaneously deconstructed and parodied in two different episodes:
    • In "His Hero", Billy is this because he thinks using violence against evil is pointless. He encourages Finn and Jake to find ways of doing good other than fighting evil, but it's difficult for them. Very difficult.
    • Jake himself makes a go at this in "Crystals Have Power". Unfortunately, he chooses a very inopportune moment because Finn is kidnapped shortly after.
  • Adipose Rex:
    • Subverted with the Ice King. He appears fat with his robes on, but in "What is Life?", he is revealed to be very skinny, but with an abnormally large chest. In "I Remember You", he's fattened up to typically normal proportions, but he only lifts his robe up to specifically talk about how he's been working out for his chest.
    • The original Lemongrab became this between "Too Old" and "Lemonhope", with a horrible twist in his Character Development to boot.
  • The Adjectival Man:
    • The... "Magic Maaaaaan!
      • Nowadays he's known as Normal Man!
    • Manish Man.
    • As it turns out, its just the way people are named over on Mars.
  • Adobe Flash: The series has very briefly used this in only two episodes, which were merely for tweening to make things move faster and better, first in Belly Of The Beast, when the lava comes into the monster's belly and everything is shaking. The lava and the bears trembling and screaming were animated in Flash too. The other episode to use Flash for one scene was Power Animal, which was used for Jake's dancing.
  • Adorkable:
    • Fionna in the genderswapped episodes.
    • Finn and Flame Princess in "Burning Low."
    • Ice King certainly has shades of this.
  • Adult Fear:
  • Aerith and Bob: Played with. Either you have a noble title (Ice King, Duke of Nuts, Princess Bubblegum, Marceline the Vampire Queen, and many more) or you're Billy, Jake, Bob, and so on.
    • Played straight with Lady Rainicorn (where "Lady" is ambiguously presented as a name and a title at different times) and her parents, Ethel and Bob.
    • The episode "Go With Me" revealed Princess Bubblegum's first name to be Bonnibel, thus presenting a strange one-woman case: she went from "Betty" in the old prerelease publication to the more whimsical "Bonnibel" in the series.
    • In "Jake the Dad", Jake's puppies are named Charlie, Viola, Jake Jr. (who happens to be a girl), Kim Kil Whan and T.V.
  • An Aesop: Sometimes subverted, e.g. in Freak City and Witch's Gerden, but often played completely straight, albeit in weird ways. For example, Finn is taught not to break promises by being punished by the Gumball Guardians.
  • Affably Evil:
    • Marceline's dad really loves his job... And his job just happens to be being the Lord of All Evil.
      "Stompin' on ants. Suckin' their souls. Stomping on ants. Souls, souls, souls."
    • Peppermint Butler is implied to be this.
  • Affectionate Gesture to the Head: Done a few times in the series.
  • Affectionate Nickname: Princess Bubblegum gets a ton of them: PB, Peebs, P-Bubs, Preebs, Prubs... the list goes on. In "Reign of Gunters", Finn calls her a different nickname every time he sees her.
    • Finn in particular is a big nicknamer. He tends to go by initials: FP, LSP, IK... it's rather touching when Flame Princess returns the favor and calls him FTH in "Vault of Bones". There are also characters with simple nicknames, like Marcy and Lady.
  • After the End:
    • The main story canon is set in a rejuvenated world following a nuclear holocaust known only as the "Great Mushroom War", which apparently mutated most surviving organisms. Marceline's childhood is set just after the war, 996 years before the events of the show, with the burning cities of man in the background. In "Holly Jolly Secrets", it is revealed that Ice King lived through this.
      Simon: [The visions] tell me the secrets of the ice and snow. That the power of the crown will save me with its frost. I don't yet know what this means.
    • In "Finn the Human", Finn wishes that the Lich never existed. This episode reveals that the Lich was created by the apocalyptic war, and his presence made things even more apocalyptic. In the alternate universe where he never existed, the Ice King/Simon Petrikov stops the Lich from causing the world as Finn knows it by sacrificing himself. However, this causes the crown to become angry and freeze the entire world for 400 years. The setting could still be considered post-apocalyptic.
    • In the epilogue of "Lemonhope" (implied to be around a thousand years later) we see that Ooo itself is in this state: the Candy Kingdom had become an advanced Skyscraper City with automobiles and aircraft before being abandoned, Finn and Jake's tree is now massive and reaches well into the clouds, and the Ice Kingdom is a regular mountain range.
  • Alas, Poor Villain: The Ice King in "What Is Life?"
    • Also the Ice King in "Princess Monster Wife."
    • The Ice King in "Holly Jolly Secrets II."
    • The Ice King in "I Remember You."
    • Cute King, when he fails to be a threat.
    • For some, Magic Man's history with his girlfriend. He obviously cared for her dearly, and misses her a great deal. Only in those moments was he portrayed as a human, hurting character.
    • Donny the Grass Ogre.
      I'll never forget you, Finn.
    • Lemongrab in "Too Young" when Finn and PB beat him up and make him cry, in "You Made Me" when he goes crazy from loneliness, in "Mystery Dungeon" when he almost dies, and in "All Your Fault" when he almost starves to death by bringing all of his food supply to life to make himself a family. This poor jerk really can't get a break, can he?
  • A.I. Getting High: In "Be More", BMO is clearly shown to get high from repeatedly deleting files for himself. The episode action begins when he accidentally deletes a vital system file.
  • All There in the Manual:
    • Pen's form spring account occasionally gives away future developments and semi-frequently fleshes out the backstory of various characters. The same goes for the production blog; for example, it's why we know that dress of Marceline's in "Henchman" is made of whywolf.
    • Thanks to the production blog, we know that the race of Fish People that appears in "Susan Strong" is known as "hyoomans".
  • Alliterative Family: Jake's brother is named Jermaine and his father is named Joshua. Plus, Pen has played with the idea of giving Jake a sister named Jessica. Jake's mother's name is Margaret, though.
  • All Women Are Lustful: Especially in the early seasons (excepting PB and Marcy), where all the princesses assume on multiple occasions that Finn is into them or, in "Loyalty To The King", flock to Ice King without his beard. There's also a herd of snail ladies who like Snorlak's beatboxing. In later seasons this was toned down though, with a load of princesses given more distinct personalities that don't have anything to do with men.
  • Alternate Continuity: The Adventure Time comics are set in their own continuity and don't factor into the show, according to Word of God.
  • Alternate Universe:
    • "Finn the Human" introduces one called Farmworld (the name is All There in the Script) where the Lich never existed, and as a corollary, the Mushroom War that created him never happened. Earth is still relatively normal, but Simon Petrikov/The Ice King is dead, having been pinned to the ground by the initial bomb of the Mushroom War in an otherwise successful attempt to stop it; humans aren't subject to Black Bead Eyes or The Noseless, and are still the dominant civilization; Finn is a farmer's son and now has said facial features along with, for reasons unknown, a simplistic robotic arm; Jake is a normal dog; and Marceline is an old woman (apparently, she never became a vampire, which was the reason for her eternal youth). Finn dons the Ice Crown to put out a fire but goes insane and causes the bomb to detonate, bathing Jake in radiation and turning him into a Lich.
    • "Puhoy" introduces another alternate universe called the Pillowverse.
  • Altum Videtur: The incantation for banishing/releasing Marceline's dad to/from the Nightosphere is "Maloso vobiscum et cum spiritum", which is roughly "evil be with you and with your spirit" in Latin. Other instances occur throughout the episodes.
  • Always Chaotic Evil: The inhabitants of the Flame Kingdom. They'll casually admit to it when asked.
  • Amazing Technicolor Population: Applies to a lot of the characters. For example, all the Marauders are a shade of blue, the cobbler is green, and Billy is grey. Justified; none of these people are human.
  • Ambiguous Gender:
    • Gunter. Not even the crew is sure of whether Gunter is male or female. Of course, none of this is helped by the fact that the Ice King seems to have named every one of his penguins Gunter (or some variation thereof). It's hinted that it's a name he gives to anyone close to him while under the crown's influence.
    Jake: Gunter's a WOMAN?!?
    Ice King: What?! No!... (lifts Gunter up and flips the penguin upside down)
    • "BMO Lost" has BMO & a bubble who sounds like a man taking care of a baby together &, at the end, BMO & Bubble decide to get married. The bubble is likely also genderless.
    • In Farmworld, Finn's baby sibling is naked, but of course we never see anything. Farmworld Finn only addresses the kid once, as "Younger Sibling."
  • Ambiguously Evil: Ricardio at first.
  • Ambiguously Gay:
    • Abracadaniel at first. He didn't want to kiss Princess Bubblegum, and he says, given the opportunity, he would "turn and push". He would even rather die than kiss her. "I'm going back to my cave to wait for someone to kill me." There are numerous more pieces of evidence like turning a wizard pink and turning Ice King's weapon into a butterfly, as well as looking remarkably like a set of male genitalia. The cherry on the sundae? He basically has the power over rainbows. He eventually does change his mind about kissing PB, though.
    • Prismo, big time. He is a pink Living Shadow with a lisp and an occasional limp wrist. Look at his reaction when Jake tells him he loves him. When he and Jake are sitting in the hot tub talking about relationships, he says he doesn't want to be in a relationship because he "Doesn't want to have to talk about everything for hours before doing it," and Jake even remarks that he has a very bleak view on relationships. It helps that his "reasons" show that he's clearly never really dated a woman before. Then there's the "Call me" letter he gives to Jake at the end of the episode. Then there's the scene with the Cosmic Owl. Did we mention the Ho Yay towards Jake?
    • Huntress Wizard competed for Princess Bubblegum's kiss as well.
    • Both of the Lemongrabs. They live together, have no problem with hugging while they're butt naked, have many children, love each other very much, "keep each other company in lemony bliss," and insist that Princess Bubblegum "call first" before visiting. They refer to each other as "brother", which does not necessarily reduce the ambiguity.
    • Princess Bubblegum in "Sky Witch" has Princess Bubblegum deeply sniffing the shirt that Marceline gave her. And according to Maja the Sky Witch, it has tons more sentimental baggage than Hambo. Hambo is the sock-monkey doll Simon Petrikov gave Marceline when she became his adopted daughter after the Great Mushroom War.
  • Ambiguously Human: Pretty much every apparently human character in the show aside from Finn and his father Martin, to the point that 'Finn the Human' is his actual title. The only exception is Susan Strong, and even she isn't confirmed to be one, though it's pretty strongly suggested. As of the Islands miniseries, it has been confirmed that she is indeed human, although she has been given some cybernetic implants. In addition, she hails from an island containing the last remnants of the human race, with the aforementioned exceptions of Finn and his father.
  • Ambiguously Jewish: Jake, whose picture in the Xmas special suggests this.
  • Amulet of Concentrated Awesome:
    • The ice crown for the Ice King. ...And the crystal apple for Tree Trunks. Not to mention Marcie's family's badge of office.
    • One episode revealed that Bubblegum had one that was used to power the nigh-invulnerable Gumball Guardians, but she lost it. Although she's since recovered it, she has never used it since.
  • Amulet of Dependency: The Ice King's Crown. It's the reason he's been able to stay alive so long.
    "This magic keeps me alive, but it's making me crazy. And I need to save you. But, who's going to save me?"
  • Amusing Injuries: Averted more often than not. When someone gets beaten up, it's treated quite seriously.
    • Averted in "No one can hear you" in which Finn has both his legs broken and Jake gets a concussion and both are knocked out. When Finn awakes (several months later) Jake's injuries and isolation have left him a little unhinged and Finn wears a cast to deal with his broken legs and is disturbed by Jake's delusions
  • Ancestral Weapon: Joshua, Finn's and Jake father, possessed a sword created from solidified demon blood. He promised in a series of holotapes that if the two completed a dungeon, it was theirs to keep. And so, Finn slew the giant one-eyed monster guarding the sword, making it his third sword.
  • Anchored Ship:
    • Finn and Princess Bubblegum.
    • As of "Incendium" and its sequel "Hot to the Touch", Finn and Flame Princess. In "Burning Low", the latter is de-anchored, and as of "Earth and Water", re-anchored.
  • And I Must Scream:
    • For some reason, Bubblegum keeps a potion that will "paralyse you FOREVER!" lying around. In an unlabelled jar.
    • Both Goliad and Stormo end up with this fate as they are forever trapped in a mind duel being perfectly even opponents. Also a Heroic Sacrifice for Stormo.
  • And Now You Must Marry Me: In pretty much every episode involving the Ice King.
  • And the Adventure Continues: Right from the very first short. "Look Jake! Some ninjas are stealing that old man's diamonds!"
  • Angrish:
    • LSP gets a bout of this in "Trouble in Lumpy Space" when she talks to her parents. She has displayed it on several other occasions, too.
    • Lemongrab has a real problem with this.
  • Animals Lack Attributes: Some of the cats in the show are drawn with an anus.
  • Animate Inanimate Object: Finn does this a lot, like say with a sandwich in "Another Way", but the crowner episode is "What is Life?"
  • Animation Bump: There are splashes of this here and there.
    • Special mention goes to Jake's dance in "Power Animal", which is animated in Flash.
    • Adobe Flash was previously used in "Belly of the Beast" for the scenes with the lava.
    • James Baxter the Horse, whose entire existence is partly built around this trope. He is animated and voiced by a legendary animator of the same name.
  • Another Dimension: Lots of these.
    • Lumpy space: What the lumps?
    • The Land of the Dead: c.f. Peppermint Butler.
    • The Nightosphere: Marcie's family.
    • The Crystal Dimension: With your new supreme ruler: Tree Trunks.
    • The Spirit World: Crazy, crazy, crazy in your face all the time.
    • The Enchiridion can open a portal to other dimensions. "The Lich" ends with Finn, Jake, and the Lich entering the portal.
  • Anthropomorphic Food:
    • There are several kingdoms in the show whose citizens are primarily food. The Candy Kingdom, Duchy of Nuts, Wildberry Kingdom, Breakfast Kingdom, etc.
    • Knowing this show, it was only a matter of time until a Giant Burger Monster was shown.
    • There is also mention of a character named Meatman. Best not to think about that too long...
    Jake (in his sleep): No, Meatman... I'm sorry, I won't eat you anymore...
  • Anti Anti Christ: Marceline, figuratively in the arc with Hunson Abadeer.
  • Apocalypse How: The Great Mushroom War, the scale being Planetary Societal Collapse, or possibly Planetary Species Extinction. There is certainly a lot of evidence of a Post Nuclear Apocalyptic setting (like missile shells and such). If this is the case, then the War definitely caused a Depopulation Bomb. This is pretty much confirmed and gets some bits of Continental Physical Annihilation added in Season 4. In "Sons of Mars" we get a brief view of the Earth from space. There's a large chunk of the planet missing. Also, Princess Bubblegum's holographic diagrams in "Burning Low" shows a rotation of the Earth in the bottom left corner of the screen.
    • Also, while easy to miss, there is a fact that Enchiridion doesn't show Mercury while zooming onto Solar System.
  • Appropriated Appellation: In "Susan Strong", the eponymous character unwittingly names herself when Finn asks her what her name is, and she's still struggling with the word "Sun": "Suh... Sun."
  • Arbitrarily Large Bank Account: The entrance to their house is filled with gold and jewels, as well as several other rooms in their house. Yet Lady Rainicorn's parents assume Jake is rich because he "Owns a human butler" not even acknowledging the hordes of treasure lying around.
  • Art Evolution: Compare the animation of the third season to the animation of the first. ...Though your take on it could differ depending on which episodes you look at.
  • Art Shift:
    • Belly Of The Beast and Power Animal each used Adobe Flash in one scene.
    • The game-world segments of "Guardians of Sunshine" are done in crude 3D computer graphics.
    • "A Glitch Is a Glitch" is animated in 3D.
    • Food Chain takes on more of the aesthetic of guest director Masaaki Yuasa
    • Water Park Prank is done in a completely different style.
    • Bad Jubies is Stop Motion animated.
  • Artistic License Law: Majesty, Highness, Sire, and My Lord are used interchangeably for princes, princesses, kings, and dukes.
  • The Artifact: Not in the show itself, but Cartoon Network's official promos still use audio of Finn shouting "A-aa-dventure Time!" recorded before Jeremy Shada's voice changed.
  • Artifact of Doom:
    • The Ice King's Crown is revealed to be this in "Holly Jolly Secrets".
    • Marceline's Dad's amulet turns its wearer into a chaotic evil monster dedicated to ruling the Nightosphere with an iron fist.
  • Ascended Fan Fic: "Adventure Time with Fionna and Cake" started out as a Gender Flip What If? comic by a character designer of the show, Natasha Allegri. Pen liked the drawings and decided to make an episode based off the idea. Her comic was itself inspired by Rule 63 art of the cast from drawthreads on 4chan's /co/ board.
  • Ass Shove: Beemo takes advantage of Finn's vulnerable tear-filled state to play Kancho on him. He used his whole hands instead of just his index fingers.
  • Asshole Victim:
    • Ice King in "Loyalty to the King".
    • The criminal candy citizens who volunteer to live with Lemongrab in exchange for amnesty in "You Made Me," and are later tortured by him.
    • Lemongrab becomes this in "Mystery Dungeon," when a giant monster grabs him and literally squeezes all of the blood out of him as he cries for his mommy. He almost dies, too- but he did have it coming. He was this earlier, in "Too Young" when PB and Finn prank him so hard that he cries, but he wasn't quite as much of an asshole in that case, just annoying.
  • Astonishingly Appropriate Appearance: Most of the royalty have more human-looking appearances than the other inhabitants of their kingdoms. The most obvious examples are Princess Bubblegum, essentially a pink human woman who lives among much less humanoid candy creatures, and the Ice King, who is the only inhabitant of his kingdom not literally made out of ice or snow other than the penguins.
  • Attack Its Weak Point:
    Ice King: FOOL! Your powers are no match for my magical crown!
    (Jake knocks off the crown.)
    Ice King: MY POWERS!
    • The giant ruby on the Snake-Armed Ruby Brainbeast's back.
  • Attractive Bent-Gender: Everyone in the gender-swap episodes, most notably Fionna, who, inexplicably, appears to be at least sixteen or seventeen years old instead of twelve or thirteen. Also, the Ice Queen, who looks about twenty-five years younger than the Ice King. Notably, she lacks the Ice King's enormous beard (which is often mistaken for a fat gut), is missing the long, pointy nose, and wears a beautiful blue gown instead of a loose, featureless blue robe. Averted with Lumpy Space Prince, who looks exactly like Lumpy Space Princess with a seedy teenage mustache.
  • Aura Vision: Princess Bubblegum creates a machine that can show peoples auras. Finn wants to see what Peppermint Butler's aura looks like, and he gets very nervous.
  • Auto-Tune: Finn sometimes (but not always) sings this way ever since he swallowed a tiny computer sometime in the past.
  • Awesome Mc Coolname:
    • Lord Monochromicorn (Lady Rainicorn's male counterpart).
    • Goliad. C'mon, you've gotta admit she's got a pretty awesome name. It sounds like the title of an epic or something. Part of the Texas Revolution actually.
  • Awesomeness Is a Force:
    Gate guard: [Why] did you die?
    Finn and Jake: ...Because we're awesome!

  • Back from the Dead
    • As of "Crystals Have Power", Tree Trunks, except she didn't really die.
    • In "Mortal Folly" and "Mortal Recoil", Bubblegum was frozen and shattered, then surgically reincarnated as a younger version of herself since the surgeons ran out of pieces to put back together.
    • In "Sons of Mars", Jake is killed on Mars in place of Magic Man and Abraham Lincoln, the king of mars, trades his own soul to bring Jake back.
    • In "Ghost Fly", Jake is temporarily killed by BMO's heart-stopping punch.
    • In "Wake Up", Prismo is killed upon his body being awoken by the Lich, who then proceeds to turn it to ash. In "Is That You?", he is brought back to life by turning an alternate version of Jake into a host body, which then turns into Prismo's original host body.
  • Back for the Finale: While the "Elements" miniseries isn't the actual finale it is part of the final season and features all four realms of Ooo so almost every character has some sort of cameo (except for those who were in the "Islands" miniseries).
  • Back Story Horror:
    • It may not seem like this show would have a horrifying Back Story, but when you realize this show takes place after a nuclear event...
    • The Ice King's origin brings with it a hefty dose of tragedy and creepiness.
  • Badass Adorable: Due to the style of the show many characters can fall under this trope.
  • Badass Beard:
    • Billy has a long white (formerly red) beard that goes down to his chest.
    • Most (alternate universe) depictions of Finn as an adult have him sporting one.
  • Badass Grandpa: Colonel Candy Corn has his moment in the Episode "Something Big," where he uses himself as ammo, landing right in front of the enemy. He then proceeds to kick major evil ass.
  • Badass Normal: Finn himself, naturally. He's an ordinary teenage human boy that regularly beats down monsters, wizards and eldritch abominations. Even with the help of a magic dog and some fancy swords, Finn himself has no special powers.
  • Bald of Awesome: Older Billy.
  • Bambification: Very much averted with the Freak Deer.
    • Averted again in "Jake the Brick", where a deer acts as the antagonist of Jake's documentary, stealing the bunny's carrot then later destroying his burrow.
  • The Barnum: The self-styled King of Ooo.
  • Bears Are Bad News: The first dungeon boss of the video game is a bear with a chainsaw strapped to its back.
  • Beast of Battle: The Ancient Psychic Tandem War Elephant, as featured in "The Limit".
  • Beauty Equals Goodness: Seems to be a staple of the show, whether unintentional or intentional, as Finn and Jake are quick to label anyone as "evil" based solely on appearances alone. Marceline, while not exactly Good All Along, is nice to Finn and Jake after they impress her. With Ricardio, their assessment that he "looks evil" proves to be completely accurate. Often invoked, like in "To Cut a Woman's Hair":
    Jake: If she [the Tree Witch] was good, she wouldn't be so ugly...
  • Beauty Is Bad:
    • Except when the show makes exceptions, such as with the Guardian Angel and the Dimple Plant.
    • Once again played straight with the Fruit Witches in "Dad's Dungeon".
    • Flame Princess is a teenager who does seem fairly innocent. However, even her own father calls her evil; and boy, does she show it. Finn, meanwhile, insists that "She ain't evil. She's passionate."
    • Ice Queen from "Fiona and Cake". Physically, she's much more attractive than Ice King; but while the Ice King has tinges of comedy in his attempts to kidnap Princess Bubblegum, Ice Queen just ends up storming the castle, launching a giant ice spike to break the wall.
  • Be Careful What You Wish For: A major theme of the "Farmworld Trilogy". Due to unforeseen results of the wishes he grants, Prismo, an all-powerful being inhabiting the Time Room, actually points out to Finn and Jake that his wishes tend to have ironic twists. Finn is Genre Savvy enough to realize that simply stopping the Lich's current scheme is not adequate, since the Lich could simply try a new plot, so he wishes for the Lich to never have existed. This creates a timeline where Simon Petrikov froze the bomb that kickstarted the Mushroom War and created the Lich, resulting in (without going into the details) Finn donning the Ice Crown and going insane, causing the bomb to go off and turn (normal dog) Jake into the Lich. In an attempt to avoid Jake's wish from screwing up, Prismo basically tells Jake what to wish for—retroactively changing the Lich's wish, which solves all immediate problems, at least for the moment.
    • The series actually reconstructs this trope by showing just why wishes tend to backfire when they're made. Prismo tells Jake that it's because wish magic tends to follow Exact Words in execution and consequences can be avoided by being very specific in the wording.
  • Bedsheet Ghost: In "Too Young", Finn and Princess Bubblegum stage a 'prank' on Earl Lemongrab by dressing up as bedsheet ghosts, running up to Lemongrab and punching him in the stomach.
    • In "Ghost Fly", the ghosts in the treehouse all look like this, including Jake's soup.
  • The Beforetimes: Source video tapes that start with a reference to the mysterious FBI.
  • Beneath the Mask:
    • There are times when Princess Bubblegum shows she's not as innocent (or sane) as she appears, like when she told Finn about the Paralysis Potion she made for no observable reason. There are hints in later seasons that she was quite ruthless in the past. In season 7 episode 25, "The Thin Yellow Line", the Banana Guards fear her for this reason.
    • Likewise, Finn finds out Marceline is a lot nicer than she seems on the surface.
  • Benevolent Genie: Prismo. He's so nice he even admits that all his wishes have a catch, and walks Jake through getting the best possible outcome for himself and Finn. When Jake, at first, wants to waste his one wish on a sandwich, Prismo just makes him the sandwich (then conjures up a jar of pickles for good measure) and allows him to save his wish for later.
  • Beta Couple: Jake and Lady Rainicorn.
  • Betty and Veronica: There are light elements of this, with Finn's crush on Princess Bubblegum (Betty) and occasional confused emotions regarding Marceline the Vampire Queen (Veronica) (even though they've made it clear they don't want to date each other). After "Incendium", the formula becomes even more tangled with Flame Princess included.
  • Beware the Nice Ones: Aside from the fact that both Bubblegum and Finn can get a little... iffy when provoked, apparently the possessor of the most evil soul in Ooo is a Gunter. And sure enough, one later almost takes over the Candy Kingdom on its own...
    • Wildberry Princess is probably the most soft-spoken of any of the princesses and seems incredibly innocent in most of her appearances. In "Furniture and Meat" she sentences Finn and Jake to death by being dipped in molten gold for insulting her.
  • Bi the Way: Jake has a secret crush on Billy. Wonder what Lady Rainicorn would say...
  • Big Bad: The Lich, an Omnicidal Maniac with a bad habit of not staying defeated. No method of defeating it has ever worked twice, and it's uncertain whether it's even possible to kill or contain it permanently.
  • Big Good: Billy, until the Lich killed him.
  • Big "NEVER!": When Abraham Lincoln tells Finn he needs to believe in himself in the pilot.
  • Big Sister Is Watching: in "You Made Me", it's casually revealed that Princess Bubblegum has CCTV cameras all over the Candy Kingdom. Her banana guards watch citizens while they sleep.
    • While the citizens sleep, not the banana guards, although given their general incompetency, that interpretation is possible as well.
    • In "The Cooler" it's revealed she spies on more than just citizens of her own kingdom.
  • Bilingual Bonus:
    • Anything Lady Rainicorn says, since she speaks in Korean.
      • In "My Two Favorite People," this exchange between Lady Rainicorn and Jake after Jake asks her if she knows a joke:
    Lady Rainicorn [in Korean]: I can't think of one... but remember the time when we ran naked through that farmer's cabbage patch? (Giggle) He was so offended!
    Finn: What's the joke?
    Jake: Uh... well, the joke doesn't... translate very well...
    • In the end "From Bad To Worse", Lady Rainicorn reveals that she didn't free the zombified Jake due to Idiot Ball.
    LR: I wanted you to bite me.
    • Lady's long monologue at the beginning of "Lady & Peebles" was about her recurring dreams about zombies attacking her family and her stress about it.
    • Princess Bubblegum speaks German on occasion, for reasons not entirely clear. For example, in the episode "What have you done?".
      PB: I'm so happy! I could... I could... (attempts to flip bed, then faints.)
    • Jake seems to speak a little Japanese. In the episode where they are trapped in the Nightosphere, Jake encourages Finn with a Japanese line roughly translated as "Do your best very well."
    • The antagonist of the episode "The More You Moe, the Moe You Know" is a robot named AMO who was corrupted by his programmed need to receive love. In Latin, "amo" means "I love."
  • Bilingual Dialogue: Jake, and apparently no one else, seems to speak Korean as well as Rainicorn. She can understand him when he's speaking English, but he does translate a joke for her once.
  • Bizarre Alien Biology: Whenever the Soft People get scared, they cry out their armpits, or "go wee wee".
  • Black Bead Eyes: The standard design of most characters' eyes in the main continuity, including Finn. Human characters in the "Farmworld" timeline have more realistic eyes. It is unclear whether this is simply a different design aesthetic or an indication that most humanoid characters in the main continuity (like Finn, Bubblegum, Marceline, etc.) really do look different from "regular" humans due to mutation.
  • Black Comedy: The show does touch on some relatively dark themes, but never quite takes itself seriously. Especially in Season 4 and parts of Season 3. The most egregrious examples of this are "Princess Monster Wife", "Holly Jolly Secrets", "No One Can Hear You", and Princess Bubblegum's failed science experiment, Lemongrab.
  • Black Eyes of Evil: The Lich King.
  • Bling-Bling-BANG!:
    • Finn's golden sword and his twin katana swords. Finn's female counterpart Fionna has a ruby sword.
    • The Ancient Psychic Tandem War Elephant has frickin' golden double barrel shotguns for tusks!
  • Blue and Orange Morality: Flame Princess seems to mainly think of things in terms of elements before anything else. She also seems to think that everything has a single purpose. She also thinks that hurting her for fulfilling her purpose to burn people to death is odd.
  • Body Horror:
    • Many of the Magic Man's spells. They tend to involve turning sentient beings into body parts or inanimate objects, fusing people together or turning them bald.
    • Most of the Lemon Children are grotesque, deformed creatures, including some that appear to be little more than sentient piles of goo. The Lemongrabs love them all the same, though, and are ever compelled to create more of them.
  • Book Ends: "Food Chain" begins and ends with Candy children playing.
  • Born of Magic: It's arguable how much magic vs. science is used in the creation of all the Candy Kingdom residents, especially when Chemistry Can Do Anything, but they are all largely described as beings of magic.
  • Borrowed Catchphrase:
  • Bottle Episode:
    • "Still". The entire episode takes place inside the tree house and only four characters are featured.
    • "Shh!" takes place inside the tree house and stars only a handful of characters, plus Finn and Jake only speak out loud once at the very end.
    • "Rainy Day Daydream" takes place entirely in and around Finn and Jake's house, and besides some invisible enemies, only features Finn and Jake.
    • "Time Sandwich" has a couple of imaginary sequences, but the actual events all take place in or just outside Finn and Jake's house.
  • Bowdlerise: Various episodes were edited before production or release. This trope has been taken Up to 11 in Australia. See here for a list of examples.
  • A Boy and His X: A boy and his talking, shape-changing dog brother.
    Jake: Think happy thoughts - little cute bees, little babies, tiny, tiny bunnies...
  • Brain Monster: Gunter briefly becomes this leading up to the sixth season finale, after a head injury literally splits his head open, and Gunter remembers that he is in fact Orgalorg, an ancient Eldritch Abomination from space, prompting his brain to hijack Princess Bubblegum's spaceship.
  • Brainwashed and Crazy: The Ice King. As is revealed over the course of the series, his crown is the source of all his power, granting him extended life and control over the forces of nuclear winter, but destroys his connection with reality.
  • Breaking the Fourth Wall:
    • The Easter Egg snail always waves at the viewers.
    • In the "Graybles" episodes, Cuber acts as host and talks directly to the viewer.
      "See if you can guess the theme by the end of the episode, okay?"
    • In the Adventure Time game Hey Ice King, Why'd You Steal Our Garbage!!?, Jake makes a comment about finishing the game right before going up against Ice King - who refers to himself as 'the final boss' a moment later.
  • Breather Episode: "Box Prince", which is a relatively "normal" episode in the middle of an action-packed and progressively arc-driven season, to the extent of feeling like a throwback to earlier seasons.
  • Brick Joke:
    • 'Mind Games', by 'J. T. Dawgzone'. In "Reign of Gunters", Finn mentions reading this book: Jake is appalled and replies that the book is "really bad advice" and should only ever be read "for laughs". In the next episode, "I Remember You", it turns out that the book is the Ice King's chief reference on 'how to get ladies'.
    • In "Ricardio The Heart Guy" when Finn tries to impress Princess Bubblegum, they start talking about Zanoits, and he asks if they're good things or not. In Ricardio's other episode, "Lady and Peebles", after Finn recovers, Bubblegum informs him that Ricardio poisoned him and Jake with Zanoits.
    • In "BMO Noire", Finn and Jake go to a party, leaving BMO alone. When they return, Jake has lipstick all over his face and an arrow in his head, and Finn is carrying a dead Sea Lard. It isn't until nearly 30 episodes later, in "Princess Potluck", that we see the other side of this.
    • "The Other Tarts" contains a small gag about Cinnamon Bun's stupidity, in which Princess Bubblegum says he is "half baked". Cut to "The Red Throne", over one hundred episodes later, where Cinnamon Bun takes a fireball to the face which "fully bakes" him and leaves him smarter.
  • Broken Ace:
    • Billy, formerly a great adventurer, becomes thoroughly disillusioned with his lifestyle, seeing it as a pointless endeavour. He gets better, though.
    • By the end of Season 3 and beginning of Season 4, Finn was so heartbroken and confused about his emotions that he had a multiple episode-long breakdown.
  • Broken Aesop: Let's just say this show doesn't take the whole And Knowing Is Half the Battle thing too seriously.
  • Broken Bird: Adventure Time seems to thrive on these kinds of people, of course the land of Ooo cant be completely saccharine.
    • The most significant example of them all though would have to be Marceline, from a extremely rough childhood of having to witness the apocalypse as a very young child, the other survivor who was her father figure got a case of magical Alzheimers and remembers nothing of his past relationship with Marceline. She had past fallout with Princess Bubblegum who is implied to be her girlfriend in the past, her Lack of Empathy that she cant seem to fully control, and is implies to have self esteem issues and frightens people away so that people won't get to know her than abandon her, as the poor girl has had to go through pretty much her entire 1000 years of existence.
  • Broken Pedestal: Finn was really set in the idea that his birth father was a good guy...
  • Bunny-Ears Lawyer:
    • Princess Bubblegum is eccentric, and a bit Cute and Psycho, but a good Cute Psycho. However, she cares deeply and personally about her citizens, to the extent of considering herself their mother in more ways than one, and will do anything to protect them. Just don't piss her off.
    • When characters call on Finn to be a hero they also deal with the fact that he's a little boy and when they deal with him as a little boy they also must account for his heroic status. This is much less of a factor for the more mature Fionna. (Who actually wears bunny ears.)
  • The Bus Came Back:
    • Susan Strong in "Beautopia".
    • In "Hot to the Touch", NEPTR of all people came back.
    • In "Sons of Mars", Magic Man makes a return after his introduction in "Freak City", and Abraham Lincoln is seen for the first time since the Pilot.
    • "King Worm" sees the return of, well, King Worm (the giant worm from "Evicted"). As well as the brief appearance of Fear Fester from "Ocean of Fear".
    • Billy shows up again in the Season Four Finale "The Lich". But not really.
  • Butt-Monkey: The Ice King

  • Calling Your Attacks:
    • Finn calls his jump-kick of the Ice King. It's actually a punch. "Psych!"
    • Hunson Abadeer: "Karate chop! Karate kick!"
  • Calvinball: The "Card Wars" episode features the Card Wars game, a holographic card game that parodies real life games such as Magic the Gathering and is overly convoluted, taking Jake two hours to teach it to Finn.
    Jake: I floop the pig.
  • Canis Latinicus: Magic often seems to work this way, such as with the Donut Witch from "Witch's Garden" and Ash from "Memory of a Memory". Averted with Joshua and Flambo.
  • Can't Have Sex, Ever: Finn and Flame Princess' first kiss creates an emotional reaction within Flame Princess that causes her to melt through the earth and almost leads to the end of the world. Not to mention that fact that merely touching her sears Finn's flesh (unless he is enchanted with Flame Protection). So she and Finn just stick to kissing a lump of coal instead as a stand in for each other.
  • Cardboard Prison: Me-Mow is captured and put in a jail cell that looks like she could easily fit through the bars without effort. Subverted however, when she declares that the jail cell will not be able to contain her. They promptly throw her into a much more secure one.
  • Cargo Envy: Jake has a hard time invoking this trope. He eventually just explains himself straight-up:
    Jake: I bet you wish you were my butt.
    Finn: ...What?
    Jake: I bet you wish you were my butt, because then the Princess would... no, wait... I bet you wish you were the Ice King and the Princess was my butt!
    Finn: What?!
    Jake: Hmm... OH! I bet you wish Bubblegum would kiss you, too, like the Ice King and my butt!
  • Carnivore Confusion:
    • The Candy Kingdom is populated by candy and other sweets. Lampshaded in "Videomakers", where Princess Bubblegum is shown drinking a sentient smoothie. In another episode, Bubblegum is stress-eating a sentient ice cream cone. The Hyoomans were intent on eating the entire Candy Kingdom (inhabitants included, minus Peppermint Butler) before being driven back, and the Earls of Lemongrab and their Lemon Children attempt the same in a later episode.
    • Peppermint Butler shows an interest in eating Finn and Jake.
    • Rainicorns apparently love the taste of human, but since they are so rare, they eat Soy People. Finn also thinks Soy People are tasty. "They say you can hardly tell the difference!"
    • Wildberry Princess often makes meat pies, being a fruit and all.
    • While visiting the Duchess of Nuts (an acorn-person, of course) with Finn, Jake had already eaten some nuts in a bowl before realizing the potential harm he may have caused.
    • In "Hitman", Jake serves himself some meat which he says came from someone called 'Meat Man'. Finn begins to question if it's okay to eat that, but Jake just shrugs him off. Later, we see Jake remorsefully mutter in his sleep on the matter.
      Jake: I had a dream about Meat Man. I think I'm gonna stop eating Meat Man.
    • After Lemonjon dissolves himself into non-living lemon candy, Finn has no problems partaking of his remains.
  • Cast From Sanity: The more Simon Petrikov uses the Ice Crown, the more he loses his mind and becomes dependent of it. The key moment where he lost most of his sanity and became the Ice King (or rather an "Evergreen copy") happened when he used it to protect Marceline from a group of radioactive zombies.
  • Catch-Phrase:
    Finn: What time is it?
    Jake: Adventure Time!
    Shelby: CHECK PLEASE!
  • Cat Ninja: In the episode "Jake vs. Me-Mow", a tiny mummy cat assassin named Me-Mow is tasked with killing Wildberry Princess. Armed with sharp claws, poison, and ninja-like ability, she proves to be quite a handful for Finn and Jake.
  • Cerebus Retcon: In the original short, Abraham Lincoln appeared as the king of Mars. At the time, this was just the height of Surreal Humor. In "Son of Mars", it's revealed that this is actually supposed to be the same person as our Abraham Lincoln, and the reason he's dead in our universe is because he traveled back in time and was killed there.
  • Cerebus Syndrome:
    • The third season and onward is notably darker and more mature (and less silly) than the previous seasons.
      • BMO's character arc has really taken an...interesting direction. Initially, BMO was developed as a comedic character to play off of Finn and Jake. As the series progressed, it became more aware of its limitations and tried to openly defy them. BMO's dream is to be a "real boy" and it talks to itself in the mirror regarding the topic. Episodes like "BMO Noir" and "BMO Lost" are also major indicators that it is something more than meets the eye. In them, BMO surrounds itself with strangely emotional characters such as Lorraine, Ronnie, Bubble, and Sparkle, and throws itself headlong into quests, as if it wishes to become a hero like Finn. Even if it would most likely die, it still continues headlong in danger, often breaking down physically or mentally. "James Baxter the Horse" has BMO caring for an egg, pretending to be pregnant... and then BMO drops and cracks the egg. BMO, of course, cries, likely thinking the egg was really a baby. The concept evokes all kinds of Fridge Horror.
      • At least one recurring character has been permanently killed off (as far as we know) in every season from 4 onwards.
  • Character Alignment: The concept of character alignment is referenced In-Universe occasionally.
    • Finn is ordered to kill an unaligned ant, which he refuses to do.
    • Hunson Abadeer's amulet "fills the user with chaotic evil".
    • Finn asks the Flame King if Flame Princess is necessarily evil or if she might be "Chaotic Neutral." Flame King says his daughter is definitely evil but agrees with Finn that the right guy might be able to change her alignment. Though she would suffer experience point penalties for acting out of her alignment.
  • Characterization Marches On:
    • The Ice King was always portrayed sympathetically, but he was originally more violent and dangerous than the Ineffectual Sympathetic Villain he would become later, even before his tragic back story was revealed.
    • Princess Bubblegum went from being peppy, social, and party-loving to being more nervous, assertive, and antisocial. Seeing her being so chipper in the first two seasons can be a little jarring. This might be justified by the extremely traumatic things that happen to her towards the end of the second season and at the start of the third.
    • Lemongrab started off as being an obsessive Neat Freak with Super OCD and just a slightly crazy Jerkass. However, his obsessive cleanliness seems to have been abandoned, and his insanity has been amped up to absurd levels.
  • Check, Please!: "Videomakers" demonstrates that, despite apparently watching tons of movies from our time, none of the characters have learned its proper usage. Cartoon Network recently started running an ad for an Adventure Time "mix your own adventure" video creator with two strange, but coherent examples, and then this:
    Ice King: I've soiled my tunic!
    Jake: Mmm, check please.
  • Chekhov's Boomerang: The Enchiridion. In its first appearance it's just a "hero's handbook," but then the Lich acquires it. It proves to be perhaps the most powerful artifact in the Adventure Time canon; when combined with various gems guarded by the princesses of Ooo (and the Ice King), it has the ability to open a portal to any of several parallel universes.
  • Chekhov's Gun: At the end of "I Remember You", a flashback shows Ice King giving a young Marceline a teddy bear, which happens to be the same teddy bear that her ex-boyfriend sold in "Memory of a Memory". This is turn becomes important in the episode "Sky Witch".
  • Chekhov's Gunman: The snail. Appears in every episode as a minor Easter Egg. Releases the Lich from his prison and becomes his vessel after he is defeated.
    • In "The Comet", Finn and Jake are separated while in space. When Finn reunites with Jake, he says he thought he lost (Jake), before revealing Jake's spacesuit empty. Finn screams, and Jake's voice tells him to chill out. Cue Jake and Banana Man on the latter's spaceship. This was referenced over four seasons ago, with Jake's croak dream.
  • Chess with Death: Well not chess, but Death likes music battles.
    • In a fun subversion, Death's favorite music is Death Metal.
  • The Chew Toy: The Cobbler in "His Hero" keeps getting injured by Finn and Jake's attempts to help people non-violently.
  • Chick Magnet: Finn, oh, so much.
    • Ice King gets a taste of this when he turns into the Nice King.
    • Jake, to an extent. The imaginary girls from "Rainy Day Daydream" for example.
  • A Child Shall Lead Them: Taken Up to 11 with Embryo Princess, who resembles a foetus in an amniotic sack.
  • Christmas Episode: "Holly Jolly Secrets Parts 1 and 2".
  • Cliffhanger: A lot of episodes end like this, most notably the ones later seasons. Usually it sets up the next episode or confuses you.
  • Clothes Make the Maniac: In "Little Dude", Finn's hat gets brought to life to by a spell that infuses it with an evil spirit. It then starts forcing itself onto people's heads and turning them evil.
  • Cloudcuckooland: The entire Land of Ooo, but a special mention goes to Lumpy Space, whose denizens are even more bizarre than the rest of the cast.
  • Cloudcuckoolander: A very large proportion of the cast, given the setting. Some individuals stand out in particular.
    • The people of Lumpy Space (especially Lumpy Space Princess) seem to abandon all shreds of sanity when they "turn lumpy".
    • Tree Trunks attempts to have tea with and seduce monsters (Tentacle monsters) when they attack her. Finn and Jake seem to consider Tree Trunks's idiosyncrasies to be due to senility, however.
    • Ice King later turns out to be a rather horrifying deconstruction of this trope. His strange behaviour actually stems from having had his mind warped and his memory erased by an Artifact of Doom. The process was slow and extremely painful, destroying his relationships with his fiancee and surrogate daughter, and it's implied that most of his actions are a subconscious attempt to replace them. By the time the main series takes place, he's barely a shadow of his old self and is miserable due to his inability to form normal relationships. And, it's implied that without the mental remnants of his old self restraining him, he would be just a violent madman rather than an ineffectual Cloud Cuckoo Lander. When this control occasionally slips, he is much more disturbing.
  • Cluster-F Bomb: Obviously we can't have literal F-Bombs in a kids show but Simon repeatedly shouting "MOTHER!" while angrily kicking at a car has all the hallmarks of this trope. He even asks Marceline to cover her ears before he starts cursing.
  • Cold Turkeys Are Everywhere: In "His Hero", Finn and Jake are persuaded by Billy that violence is not the answer and they swear to find non-violent ways to help people. They immediately run into situations where violence would be the perfect solution. They also discover that they suck at non-violent solutions.
  • Comedic Sociopathy: Martin - Finn's dad - is completely unsympathetic, manipulative in the extreme, and doesn't care how his actions affect other people. He takes advantage of every situation and person he runs across. For instance, he manages to accidentally free the leader of an oppressed group of cute little koala-people, and uses their trust to sell their "milk moth", which supplies their village with all of their food.
  • Comet of Doom: Most of season six's second half revolves around the revelation that a comet strikes the Earth every thousand years... and that's its due for its next visit soon.
    Sweet P: The comet approaches.
  • Comic-Book Adaptation: KaBoom started putting out monthly comic books starting 2012. This marks the first time a comic book based on a Cartoon Network show is put out by a publisher other than DC Comics.
  • Conspicuous CG: Adventure Time has very briefly used Adobe Flash in only two episodes, which were merely for tweening to make things move faster and better, first in Belly Of The Beast, when the lava comes into the monster's belly and everything is shaking. The lava and the bears trembling and screaming were animated in Flash too. The other episode to use Flash for one scene was Power Animal, which was used for Jake's dancing.
  • Continuity Cavalcade: Many characters from past episodes return in both parts of "Holly Jolly Secrets".
  • Continuity Creep: The first two seasons of the series have relatively little continuity and lore in them. Then, starting with the S2 finale, the show slowly begins delving into more continuous stories while still having standalone eps. By the time Seasons 5 and 6 roll around, the show features many, many Sequel Episodes that expect you to remember small background details and events that happened 20+ episodes ago.
  • Continuity Nod: Has its own page.
  • Convection Schmonvection: Averted most of the time, as non-Fire Elementals need Flame Shield cast on them before they can even enter the Fire Kingdom.
    • Played straight in the episode "Jake Suit", in which Finn and Jake not only walk around in the Fire Kingdom without Flame Shield, but Finn gets lowered into a volcano directly above the surface of the lava and only gets a singed hat.
  • Cool Horse: Lady Rainicorn and Lord Monochromicorn.
  • Cool Old Lady: Tree Trunks and the old woman who get Finn and Jake to return to beating up evil.
  • Cool Plane: Finn's paper airplane skills are something to behold.
    Finn: I'll fly the paper as an airplane down the bedroom ladder. It'll triple barrel roll past the kitchen open the fridge and cook some eggs then eat the eggs and unfold itself as it lays itself in front of Marceline's door.
  • Cool Sword:
    • Finn and Jake's family sword is made out of freaking DEMON'S BLOOD.
    • "The family sword. It's made out of babies!"
    • The grass sword. It has a curse on it that binds it to Finn at all times. When it's not being used as an actual sword, it takes the form of a grassy armband around Finn's wrist. Fast, deadly, and always on-hand.
    • The Finn Sword, made of Finn's alternate self who violated the Temporal Paradox.
    • Arguably, the coolest sword in the show is the Black Hole Sword from The Real You.
  • Covers Always Lie: Most of the title cards.
  • Crapsack World: Ooo, a post-apocalyptic land full of magical monsters ruled by royalty that range from innocent-but-crazy to outright evil. It was even worse during Marceline's childhood, which is implied to have been during or shortly after a world-ending nuclear war.
  • Crater Power: There is a HUGE crater in the Land of Ooo's Earth. Presumably, this was caused by the Mushroom War.
  • Creating Life: Appears several times throughout the series, and many characters originated in this manner.
    • Princess Bubblegum creates both Lemongrabs in her lab. Lemongrabs 1 and 2 later use the same technique to create the Lemon Children. It is implied that Bubblegum created the entire Candy Kingdom.
    • In "Goliad", Princess Bubblegum creates her successor, Goliad, using 'a fairly standard candy creature soup' as well as her own DNA. When Goliad learns to rule others by force, Princess Bubblegum creates Stormo to counter her using Finn's DNA.
    • NEPTR is created by a combination of Finn's crude engineering, a bolt of lightning and Ice King's magic in "What is Life?"
    • The Ancient Mage of Life Giving is this trope personified.
  • Creator Cameo:
    • Gingerbread man versions of creator Pendleton Ward, storyboard artist Adam Muto, and creative director Pat McHale can be seen in the background in one scene in "The Enchiridion!". Also, Gingerbread Muto can be seen in the Title Sequence (and Gingerbread Rebecca Sugar (Adam Muto's storyboarding partner) for the opening sequence to the Gender Flip episode "Adventure Time with Fionna & Cake").
    • Several episodes feature a stubbly, bespectacled face representing character designer Phil Rynda. The face shows up on minor characters and as the symbol used to summon Marceline's dad, among other instances.
  • Creepy Child: Marceline as a kid. "I'm hurting you because I love you."
  • Cross-Referenced Titles: "Too Young" and "Too Old".
  • Crying Little Kid: How Simon and Marceline met. He found her crying in the ruins of a city during the aftermath of the Mushroom War.
  • Crystal Landscape: The Crystal Dimension is a dimension composed almost entirely of crystal, inhabited by magical beings like crystal people, Rainicorns and anthropomorphic dogs.
  • Cue the Sun: In "Evicted!" to symbolize that things will start to go right for Finn and Jake. For a while, it doesn't.
  • Curb-Stomp Battle: Finn vs the Bucket Knight.
    Finn: That... suuuuuucked...
  • Curse Cut Short:
    Finn: SON OF A— (train toots)
  • Cursed with Awesome: Finn's grass sword.
  • Cute Ghost Girl: Ghost Princess.
  • Cute Is Evil:
    • Me-Mow may be an assassin, but an adorable one at that.
    • The baby pigs from "The Pods". They come out dressed in adorable costumes and seem completely innocent... until they get magic wands and start destroying the town.
  • Cute Monster Girl: Marceline. Well, most of the time. Other times, not so much...
    • Most of the princesses also qualify for this.
  • Cute Kitten: The cats from "Box Prince", specially the titular character.
  • Cuteness Overload:
    Finn: Jake, get the camera!
    Jake: I can't! I'm paralyzed by the cuteness!
  • Cuteness Proximity: In the episode "Gut Grinder", villagers found Jake to be cute and adorable, showing their affection by heavily petting him.
  • Cutting the Knot: In "Dad's Dungeon", Finn encounters a monster with a key on a chain around its wrist, obviously meant for the lock on the family sword. He simply breaks the lock through sheer force and slays the monster with the sword.
  • Cyclops: The Iceclops. Regular cyclops show up later. Also Earclops.