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Characters / Adventure Time: Finn

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Finn "the Human" Mertens
Click here to see Finn without his hat. 
Click here to see Finn from season 8 onwards. 
Click here to see Finn in Adventure Time: Fionna and Cake

Voiced by: Zack Shada (2006 pilot), Jeremy Shada (the series), Jonathan Frakes (adult, "Puhoy" and "Dungeon Train" only), David Bradley (elderly)

"Is that what you think adventurers do? Die and make all your friends feel terrible 'cause they couldn't save you?!"

The intrepid human boy and one of the two lead characters of the series. Hyperactive with a love of adventure and good deeds. That thing on his head is actually a hat. Originally 12 years old, he gets older as the series progresses. Yet, he looks no different.

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  • 10-Minute Retirement: In "Freak City", Finn goes through one of these after getting turned into a foot, during which he memorably goes into Auto-Tuned song. Though it's more thirty seconds than ten minutes. The later episode "Davey" is built around this also with him developing a split personality.
  • Adoption Angst: Finn was raised by a family of talking dogs after the parents found him as a baby. Though he loves his adoptive parents, Margaret and Joshua, he also angsts over not knowing where he came from or who his birth parents are, all the more punctuated by the fact that he's never met another human being. When he does eventually meet his biological father, he is disappointed to find that Martin does not actually care about him. Thankfully, meeting his biological mother goes over much better.
  • Aesop Amnesia: Fionna and Cake shows Finn continuing his previous habits of relying on adventuring to address emotional trauma instead of actually dealing with it. When he sees Simon in a depressed existential crisis over losing Betty and being stuck in a world he doesn't belong in, he decides to take Simon on an adventure. During the adventure, Simon brings back some past memories with Betty, though Finn tells Simon not to talk about sad stuff, believing it is better to forget about it. It's clear that Jake's death has caused him to regress to his previous mentality of repressing emotional trauma, given how Finn outright admits to Jake in the afterlife that a part of him was always waiting to die to reunite with Jake again.
  • Amazon Chaser: He often gets starry eyed whenever Flame Princess is fighting someone.
  • Amicable Exes: With Flame Princess. It took a genuinely long time and a lot of growing up until he could honestly become her friend and come to terms that they are Better as Friends, as well as genuinely apologize for his actions in "Frost & Fire" and move on. He mentions in "Elements" that he is proud of the friendship they built and that he likes having her as a friend.
  • An Arm and a Leg: In "Escape from the Citadel", Finn loses his right arm when he tries to tether himself to his father's star ship so that he won't escape from the Citadel. His grass blade mutates and envelops his arm, twisting it into a horrific mass of grassy mutated flesh, and the force of the ship flying out of the Citadel rips his grass arm off leaving him without an arm beneath the elbow. Some of the guardian's blood manages to get on his arm afterward. Sporting a flower on his stub though it seems it'll take time for the grass blade to recover.
    • In "Breezy", the arm comes back when the flower left by the grass sword turns into a tree over Finn's arm stub and leaves behind the arm covered in a waxy substance; this happens after Finn finally feels a warm, loving feeling after seeing a vision of Princess Bubblegum. Yeah, it's pretty weird.
    • In "Reboot", Finn alienates the grass sword during a moment of pacifism, causing it to detach and merge with the Finn Sword instead, forming a new entity and taking the new arm he'd gotten in "Breezy" with it.
  • Angst? What Angst?: Invoked. He hates the process of facing and treating traumatization, so he applies Brain Bleach or just suppresses his emotions outright. In fact, when confronted with disturbing experiences, he places them in the Vault.
    • Finn meets with a cloud spirit living in a drifting cloud who teaches Finn a lesson on this subject. The spirit tells Finn not to bottle up his feelings but to instead dwell on them, because that's the only way you'll ever comes to terms with those feelings. Finn eventually does learn his lesson at the end of the episode as he finally lets go of his anger.
  • Animal Motifs: Butterflies. Finn has had a lot of past lives, one of which was a butterfly, and the series goes over his metamorphosis from inexperienced boy-adventurer to a full-blown hero. This was in play from all the way back in season 3's "Still" where he summons a swarm of butterflies as his astral beast.
  • Artificial Limbs: Alternate depictions of Finn always show his right arm to be a crude prosthetic, such as his dream of himself as an adult.
    • Even applies to his past life as Shoko.
    • Also, his "lifetime" spent in the pillow universe. How the heck he lost an arm in a world made up entirely of pillows is anyone's guess.
    • Now that Finn has lost his right arm, his need for one is perfectly justified. In a recent episode we see Finn experiment with replacement arms that Princess Bubblegum made for him, which all annoy him because they don't handle anything like his old arm. Eventually the flower in his stub of an arm gives him an artificial arm made out of psychic, white glowing energy.
      • "Breezy" has the flower on Finn's arm grow into a large tree, which eventually bursts leaving behind a bit of a hollow log on his arm. When that's peeled off, a brand new, perfectly healed arm is revealed covered in sap.
      • In "The Comet," it's revealed the arm is still somewhat artificial. The thorn reappears and we see that the thorn was the Grass Sword growing. When the fake skin breaks off, we see it's a large vine that Finn uses as a whip to stop Orgalorg before it makes an arm and hand shaped vine.
      • As of "Two Swords", he matches his alternate counterparts'. After the grass sword freed itself from his body in "Reboot", and took his arm with it, Princess Bubblegum has outfitted him with a prosthetic replacement. She opts for a slender metal model instead of one made of candy this time.
      • In the series finale, he loses his metal arm in the fight against GOLB. He doesn't get it back and in fact seems content with living with one arm, at least for a while.
      • "Together Again" shows that in his final years up to his death, Finn's right arm was now completely mechanical, and though it was cruder than the one Bonnie had given him, it was sturdier and had a metal pauldron.
  • Auto-Tune: He's able to switch this effect on and off for his actual singing voice after he swallows a tiny computer immediately prior to "The Jiggler".
  • Awesome Backpack: His big, green, circular backpack.
  • Badass Adorable: He skinned a polar bear for his hat as a baby. Do the math.
  • Badass Decay: In-Universe. In the second half of Season 5. After his breakup with Flame Princess, he gets into a rut, he's more focused on wooing his old love interests when they want him doing heroic things instead. It's so bad, he gets overshadowed by Cinnamon Bun of all people (granted, he's Taken A Level In Badass.)
  • Badass Normal: He fist fights monsters or uses some other mundane tool on a regular basis; including the Lich.
  • Badass Pacifist: He prevented the Gum War without fighting Fern or Gumbald, instead using the Nightmare Juice as an opportunity to work out everyone's issues, including his and Fern's.
  • Barbarian Long Hair: While it was long, straight and beautiful during his youth, by Fionna and Cake it's grown wild and reaches out of his hat sticking every direction, pairing well with his beard and increased muscle mass to make him look like an experienced adventurer.
  • Barbarian Hero: A downplayed, Lighter and Softer example, due to him being an adolescent, and more prevalent in the earlier seasons. Finn lives in an isolated area in the Grasslands of Ooo, is fairly unsophisticated, has Blood Knight tendencies, is stronger than you would expect from the average mortal, usually forgoes wearing armor in combat,and has unbelievably long flowing hair underneath his white hat, which he skinned from a bear as a child. He also has more than a few magical nemeses, most prominently the Ice King and the Lich, both of whom he has employed direct physical force to defeat in the past.
  • Better as Friends: With pretty much everyone of his love interests.
    • With Marceline, both realized they don't have any interest in being more than friends.
    • With Flame Princess, the events of "Frost & Fire" have permanently damaged any possible romantic outcome of their relationship, with Finn betraying her trust. While he still chases her for a longer while, she refuses anything but friendship from him. After several events in his life, he came to understand that they won't be together, at least for a long while and is proud of the friendship and trust they built with each other.
    • With Princess Bubblegum, it's actually been on and off. While he did move on from her and to Flame Princess, it's evident even in Season 7 and 8 that he harbors strong feelings for her. During a vision when processing the trauma of his lost arm and the flower that was there, he saw Bubblegum there and the feeling of happiness allowed his arm (or a plant-based facsimile) to grow back. When LSP gets Finn to go to his happy place (after he succumbed to the rage of the corruption of the Fire Kingdom), it's him (or rather a younger him) with a younger PB. However, it's possible this is just because of feelings of friendship and family, or perhaps a hint that Bubblegum actually is bottling up her emotions.
    • It's initially played straight with Huntress Wizard, who finds Finn's attraction to her and her own to him inconvenient considering "exceptional beasts" such as themselves should not be together, instead trying to take on a more platonic relationship. That said, she does progressively seem to open up to the idea of romance, possibly subverting the trope, although it remains unclear by the end of the series if they're a romantic pairing yet or not.
  • Beware the Nice Ones: As nice a guy as he is, it would be unwise to get on his bad side.
  • Big Brother Instinct: He is fiercely protective over Jake, despite being the younger brother.
    • In "Evicted", Marceline kind of killed Jake for a minute. Finn's reaction was... not pretty.
    • In "To Cut a Woman's Hair", the witch merely uses Jake as a cushion (albeit in the context of Finn's requiring someone to be in "danger" in order to help her), and Finn charges.
    • When Jake is transformed into a Lumpy Space guy.
    • He also shows this towards Fern by constantly supporting and encouraging him, getting over the trauma of killing Fern by picturing him as someone Finn needs to save and killing the Grass Demon to protect him.
  • Blood Knight: He may be in it mostly to slay evil, but there's no denying that he really likes fighting for its own sake ("If you're an evil witch, I will punch you for FUN!") When he wins the Fight King's "favor," he really hams it up.
    • Toward the end of the series, he's moved on from this, and spends the last few episodes actively working to prevent a war between Bubblegum and Gumbald.
  • Bodyguard Crush: On Princess Bubblegum, though as time goes on he has more or less gotten over it, with only tiny hints that he still has feelings for her.
  • Book Dumb: See Idiot Hero.
    • Seemingly repaired as of "Dentist."
  • Broken Ace: Multiple times, but he always manages to pick himself back up.
  • Celibate Hero: After his breakup with Flame Princess Finn decides to forgo romance entirely. That is, until he mets Huntress Wizard.
  • Character Development: Happens twice, both negatively and positively. First becoming a teenager with hormones makes him more selfish, self obsessed, putting a wet dream before doing good and being prone to depression. And then in season seven/eight, after going through all that, he's an emotionally mature young man who can apologize to Flame Princess for manipulating her and can have more chill relationships.
    • On a grander scale, Finn's grown from a rowdy kid that loved fighting to a generally rational young man that's more interested in helping people as a whole.
  • Characterization Marches On: Early episodes had him be the more wild Chaotic Good half of the main duo ("I'll slay anything that's evil, that's my deal."), before making him into The Paragon.
  • Chick Magnet: So far, lots of princesses want to give Finn a peck on the cheek.
    • Also he foolishly promised a pack of princesses that he'd get them married to whomever they wanted. Slime Princess wanted him (and was only the first one to speak up).
    • During "To Cut a Woman's Hair," every princess he talks to seems to think he's in love with them (except Princess Beautiful, fortunately). He eventually gets Princess Bubblegum to go to the forest and have dinner with him.
      "If there's one thing I learned today, it's that I'm awesome at talking to ladies."!
    • The fact that Huntress Wizard is still hanging around him in "Wheels" proves it: Finn has so much game he pulls the ladies in his sleep.
  • Chronic Hero Syndrome: In one episode, he displays this, the reason being when he was a baby, he was left alone in the forest and nobody came to help him. It's downplayed in general; he takes his hero work as a calling in life, but tries not to step on anyone's toes.
  • Collector of the Strange: In "The Jiggler" it's revealed he has a glass eye collection. It's never mentioned again.
  • Colorblind Confusion: In "Red Starved", Finn's shown to be red-green colorblind after he mistakes a green emerald for a red ruby. Strangely, Jake (a dog) CAN tell the difference, and is the one to correct him.
  • Combat Sadomasochist: The kid jumped into a volcano for fun. You finish the math.
    "You just gotta imagine that every bruise is a hickey from the universe. And everyone wants to get with the universe."
  • Compressed Hair: Hair that would probably go down to his feet, until he cut it off.
  • The Conscience: Good grief yes. Finn's heroic nature counterbalances his closest's friends amoral tendencies. While it tends to be played for laughs with Jake, it's played more seriously (and more subtlety) with Marceline and Princess Bubblegum.
    Jake: Look at all this grave booty! CHA-CHING!
    Finn: Jake! You LOOTED? That's bad, man!
    Jake: Oh... I didn't know it was wrong...
    Finn: (sigh) Come on, let's put all of this back.
    Jake: What?! All of it?!
    Finn: Yes, Jake.
  • Cool Sword:
    • His first one has a blade of gold. The second has an interesting, woody handle and an Absurdly Sharp Blade.
    • It doesn't get any cooler than a black hole sword in "The Real You".
    • From "Dad's Dungeon" to "Play Date", he gets a sword made out of a demon's blood.
    • From "Blade of Grass" to "Escape from Citadel", he gets a cursed blade made of grass that can cut through anything.
    • As of "Is That You?", he has the Finn Sword, a sword made from an alternate version of himself.
    • After the Finn Sword and Grass Sword combine to create Fern, Finn wields the rapier-like blade he got from Rattleballs.
    • He gets his final sword in "Marcy & Hunson," when Peppermint Butler summons the Lord of Evil to make Finn a sword infused with the power of the Nightosphere. A giant version of this is still being used by an adult Sweet P 1,000 years in the future.
  • Cool Uncle: He seems to be so in Distant Lands while hanging out With Bronwyn. Or in Fionna and Cake where he also do quests with TV
  • Cool Old Guy: "Together Again" shows he remains just as awesome as an old man, having continued adventuring up until his death.
  • Crazy Jealous Guy: He gets extremely jealous when someone comes in the way of him and Princess Bubblegum or Jake or FP.
  • Creepy Child: From snuggling a piece of Princess Bubblegum's hair to watching Jake sleep and taking pictures, Finn can be a disturbing child at times. It's implied this is the result of some serious abandonment issues.
  • Cursed with Awesome: The Grass Sword. It is literally cursed, and while it gives him exceptional swordsman skills, he can't remove it from his person. It tried to slowly take over his arm, but once he accepted that the sword would be a part of him forever, the sword retracted to form a bracer around his wrist. He can summon it at will.
    • In the Season 6 premiere the grass sword overtakes his arm once more, this time to help him, only this time he finally loses his arm. He regains the arm some episodes later but seems have lost the grass blade in the process.
    • And then in the Season 6 finale, the grass sword triumphantly returns. Only for it to be gone for good in the Season 7 finale.
  • The Cutie: He is quite adorable at times, especially when in pain.
  • Dating Catwoman: Flame Princess is quickly revealed to be evil, or at least a dangerous wild card. Finn develops a crush on her after she attacks him. This becomes more of a downplayed example after Flame Princess's second appearance, as she becomes more emotionally stable.
  • Deadpan Snarker: He's of course very excitable, but as his voice got deeper (and he knew what apathy felt like), Shada's voice got quite excellent for deadpan lines.
  • Death Seeker: Downplayed as he's not exactly trying to get himself killed, but after Jake passed away, Finn admits that part of him is waiting for his own death just so he can reunite with him again.
  • Deconstructed Character Archetype: Two big deconstructions:
    • Kid Hero: Finn has been fighting and killing monsters and supernatural beings since at least the age of twelve (his age when the series begins). Even though he's quite cheerful and upbeat most of the time, psychologically he's really messed up. In fact the reason he manages to stay upbeat despite the horrors he's seen is because he's very good at suppressing traumatic memories (he refers to the process as "putting them in the vault"; the fact that he does it so often that he has a term for it is a bad sign). Because he's spent so much of his life fighting and adventuring, he doesn't know much about making personal connections. His emotional immaturity and Blood Knight nature drove his girlfriend away, and his tendencies toward white knighting are steadily getting creepier as he gets older. All he really knows how to do is punch things; life situations that require a more complex solution are beyond his ability to navigate.
    • Insecure Love Interest: Sure, Finn has a Precocious Crush on PB and he frequently rescues her, but she only thinks of him as a close friend at most. They come very close to confirming their ship when she is de-aged, but it's thoroughly nixed when she returns to her original age. One episode involved him singing a song about how confusing it was ("What am I to you? Am I a joke, your knight, or your brother?") that also includes his sentiment that it doesn't really matter as long as they are at least friends and get to hang out. He eventually gets over the romantic aspects when he meets Flame Princess, although he makes a few attempts to re-kindle something with PB after that relationship ends.
  • Defiant to the End: Showcased in "Escape from the Citadel" when The Lich reaches out his hand to finish him off. Finn defiantly smacks the hand away despite the fact that The Lich immobilized him with just a single word, and Finn had no guarantee that such a feeble attack would keep The Lich at bay.
  • Determinator: His very first appearance has an amusing double-subversion. Finn is told to believe in himself in order to escape his prison of ice; Finn refuses, but then breaks out through sheer willpower. In the series proper, he soldiers past numerous injuries, breaks out of the Lich's mind control, literally ignores two broken legs to save the day(s).
    • In "You Forgot Your Floaties," he's transformed into an egg. Through sheer force of will, he forces himself into a bowl of batter, and then bakes himself a new body made of bread.
  • Did Not Get the Girl: Twice, he tried with Bubblegum after her age down but this was dashed when she had to restore her age to save the kingdom from Lemongrab and she's shown no interest in pursuing romance (though the end of the series gives a very good reason why in her case). Then came Flame Princess and that lasted for awhile, but she broke it off after the incident with Ice King and any hope of getting back together with her was crushed when Cinnamon Bun professed his love for her. He does fall in love, get married and have children when he travels to the pillow world, being his most lasting relationship until he "dies". But it's ambiguous if that was real or not. Huntress Wizard seems to have likewise taken an interest in him, but due to the finale not directly focusing on their romance, this is more of a Maybe Ever After.
  • Didn't Think This Through: The reason he lost Flame Princess. Though that was just one of many examples he displays through the series. He has a tendency to act first without really assessing the situation, often making a bad problem worse.
  • Did You Just Punch Out Cthulhu?: He frequently goes there. For instance, in "Freak City" he, in a fit of rage, decides to beat up Life. In another episode he attacks a fourth-dimensional black-hole type construct, and destroys it. After he gets the cursed blade of grass he slays the Fear Feaster with it in "Billy's Bucket List". In "Escape from the Citadel", he takes down The Lich by gooping him with the blood of the fallen Guardian, which has massive amounts of healing properties, thus bringing the Lich to life into an innocent giant baby.
    • Has gone toe to toe with the Lich no fewer than four times and has always managed to throw a wrench in the Lich's plans. Of note, this makes him the only being to ever defeat the Lich more than once.
    • In "Crossover" he takes out an alternate universe version of the Lich using a Wavemotion Gun given to him by Prismo.
    • And not just our Finn... after the Lich was spread throughout the Multiverse, the Lich mentions being bested by Finn in many worlds, implying the Alt-Finns have been able to stop their Liches as well.
  • Disappeared Dad: His dad was being held in the Citadel. He doesn't care that Finn exists at all.
    • Complicated by later revelations that Martin was actually on his way to being a loving and present father when his past intervened and started him on the road to Jerkass-dom.
  • Distaff Counterpart: Fionna.
  • Dumb Blonde: He has blonde hair under his hat, and he can be quite clueless sometimes.
  • Easy Amnesia: Finn can put frightening memories in his "vault". What's disturbing is that he does it so casually...
    Finn: That one's going in the vault. Aaaaaaand... it's gone.
    • Once Finn opens the vault just a crack, he's apparently easily able to discover his past lives.
      • "Come Along With Me" reveals the Vault to contain representations of the monsters Finn was most traumatized by fighting—the Lich, the Lich-possessed Bubblegum, Brainwashed and Crazy Susan, and his own father.
  • Empowered Badass Normal: He eventually gains the ability to generate a psychic limb, giving him super powers. He loses that, but later on the Grass Sword's remains give him the power to turn his arm into a powerful vine tentacle. He eventually loses that during "Reboot" when it detaches itself from Finn to join with the Finn Sword.
  • Enlightenment Superpowers: Finn has shown high knowledge in spiritual matters, introspection and various powers born from pure enlightenment: summoning his astral beast, astral projection, controlling his own memories of past lives and making the universe give him a way to stop Gunter/Orgalorg, with auto-tuned singing, no less. It's implied this is the result of being a reincarnation of a past Catalyst Comet.
  • Entitled to Have You: Sympathetic example, but nevertheless, "All Gummed Up Inside" has him despairing about not being able to "keep" Bubblegum, not really grasping the fact she was never his in the first place.
  • Everyone Has Standards: While a Blood Knight, Finn largely refuses to kill anyone or anything that's not evil, to the extent that, in "The Enchiridion," he let out a Big "NEVER!" to being ordered to kill a "neutral" ant. Also, in "What Have You Done?", despite being enemies with Ice King, Finn made it clear that he wouldn't beat him up when Ice King hadn't actually committed any recent crimes, stating it as "against his alignment."
  • Evil Laugh: Non-evil example; in "What is Life?", Finn mischievously does this, while thinking to prank Jake after he pranked Finn himself, as a type of revenge.
  • Fatal Flaw: Lust seems to be this for Finn in later seasons, particularly in Season 5, where it's what caused his relationship with Flame Princess to fall apart
  • The First Cut Is the Deepest: Princess Bubblegum making it clear she didn't want him made him wallow for a while.
  • Foreshadowing: A lot of hints were dropped that Finn would lose his right arm starting with his Farmworld depiction. This eventually happens in the Season 6 opening.
  • For Great Justice: His reasoning for why he fights evil.
  • For Happiness: When he and Jake aren't busy fighting evil, they're just trying to have a good time.
  • Fetish: As established in the Amazon Chaser entry above, he has a sexual fetish for seeing women fight and/or fighting together with them. Wallowing in this while not being honest about it destroys his relationship with Flame Princess.

  • Generation Xerox: While not as bad as Martin, Finn has shown he's able to be be as manipulative as his father if given the opportunity to do so. It's not all bad, as his father showed physical feats that easily match his son's. Apparently, Finn shares most of his positive traits with his mother, a genuine Helper who enjoys aiding others just as much as her son does.
  • Given Name Reveal: In "Finn the Human", it turns out his Alternate Self has the full name "Finn Mertens". By "Dentist" he indicates he's learned the name and taken to using it himself, and "The Visitor" shows it is his father's surname in this timeline as well.
  • Good Counterpart: To the Lich in a sense. The Lich was born from a Green Catalyst Comet that killed the dinosaurs, Finn's the Reincarnation of the Blue Catalyst Comet.
  • Growing Up Sucks: After his breaking up with Flame Princess, Finn starts to feel things become more complicated as he grows up, and wishes to have things be like they were before.
    • Note that his romantic attachments tend to retire from dating him to spend more time leading their people (while he has none to lead).
    • The realization that his human father never loved him and never will also left him very depressed.
      • Well, not never loved him. But never will again.
  • Guest Fighter: DLC skin for Jhala in Brawlhalla.
  • Hair of Gold, Heart of Gold: Although his hair color was originally only mentioned by the creators, it's since been seen. And it is glorious. He has the associated purity.
  • The Heart: He's the only one who can get Bubblegum and Marceline to stick together; in 'What Was Missing', it's clear that their attempt to get through the Door Lord's door would have fallen apart easily without his influence. He also serves as The Conscience to them.
  • Heartbroken Badass: His love life hasn't exactly been kind to him. Being abandoned by his human dad twice doesn't make things any easier either.
  • The Hero Dies: "Together Again" opens with him having already died and found himself in the Dead World, after briefly being trapped in a Lotus-Eater Machine by a parasite.
  • Heroes Fight Barehanded: Despite owning at least two swords, Finn often fights with his bare hands.
  • Heroes Prefer Swords: Though he uses Good Old Fisticuffs much more and an ax at least once.
  • Heroic BSoD: He goes through a (hilariously brief) one every time somebody reminds him that he's almost certainly the last human.
    • Spends half of "Dad's Dungeon" like this because he thought Jake and Joshua turned against him. It's bad enough that he actually tries to eat the apples. Twice, the second time he's actually watching what the apples do to a person. Jake has to stop him both times.
    • In "Hot to the Touch," when he realizes he can neither fight or hurt his new crush the Flame Princess, nor allow her to destroy the goblin kingdom, he curls up and cries, right before briefly passing out.
    • The end of "Escape from the Citadel" leaves him with Prismo dead, his arm and sword gone, and his dad having abandoned him. He doesn't even try and swim to the surface of the lake he's in and Jake has to pull him out. He spends "The Tower" singing a Madness Mantra about how he intends to tear off his father's arm to replace his, and then spends "Breezy" having a series of meaningless relationships in a futile attempt to feel better.
    • After killing Fern in "Three Buckets," Finn loses his ability to be Ooo's protector, as every monster he fights reminds him of his dead doppelganger.
  • Heroic Willpower: Goes hand-in-hand with his many Determinator feats.
  • He Is All Grown Up: As of "Obsidian", he's now on his 20s, and he grew a lot by the time between the finale and Distant Lands.
  • He's Back!: "Billy's Bucket List". Season five zigzagged on his heroism with hormones taking precedence and making him act like a jerk, but in said episode he's determined to finish Billy's list and conquers his fear of the ocean. Though, with the revelation of his human father still being alive, more angst was to follow.
  • Hidden Depths: Lightly hinted at a few times. In particular, he may hide a desire for civilized life, as well as trauma stemming from his Parental Abandonment. He rarely if ever dwells on such things.
    Finn: I... am complicated.
    • If the video game Pirates of the Enchiridion is anything to go by, Finn, despite normally being Book Dumb in more than a few areas, is surprisingly skilled in cartography.
  • Hormone-Addled Teenager: His yearly aging leads to more complicated relationships with girls.
  • Hotblooded: Doubles with Large Ham. Throughout the series, there have been several instances where he has been intensely agitated.
    • From the "Hero Boy Named Finn" song:
    Finn: And I'm not gonna be cool... 'cause I'm pipin' ho-oooooot!
  • Hulking Out: Whenever something happens to Jake.
  • I Am Not Weasel: Flame Princess comes to the conclusion that he must be a Water Elemental due to him crying each time she's seen him and him repeatedly hurting her without realizing it. Also, the squirrel from "Up a Tree" mistakes him for a chipmunk.
  • I Can Change My Beloved: After the Flame King explicitly explains that his daughter, like everyone else in his kingdom, is evil, Finn makes influencing her to good his goal. (It definitely helps that she's on board with it.)
  • Idiot Hero:
    Why is Finn missing so many teeth?
    The creators' answer: He bites trees and rocks and stuff. He's stupid.
    • Which makes it that much more interesting when his brain works perfectly, like in "Morituri te Salutamus".
    • As shown in "The New Frontier", Finn occasionally forgets how the sun works, and is seemingly floored when Jake re-explains it to him.
    • In "In Your Footsteps", he freely gives away the Enchiridion, a "hero's handbook" he got dozens of episodes ago, because he's mostly used it for sitting on. It falls into the Lich's hands.
    • In "From Bad to Worse," he mixes random potions to stop the candy zombies. The result was a bunch of random effects, most of them made the zombies even stronger.
    • In "The Real You", Finn himself says that he's "full of stupid."
    • This is more of an early season character trait as he becomes more intelligent as the series goes on, especially emotionally.
  • I Gave My Word: Deconstructed as the events of "Slumber Party Panic" get more and more out of hand because of his promise.
  • I Just Want to Be Loved: In both a familial and romantic sense. He's at that age where he's looking for a girlfriend and is utterly devastated to find that his dad barely cares about him.
  • I'll Kill You!: A couple of times. When his picture frame of Bubblegum is set on fire after he spent hours crying over it, he snarls:
  • Important Haircut: To save Jake from eternity in a witch's butt. Since then he seems to be letting it grow out again.
    • Averted when he cuts it again right before visiting Mars with Jermaine. It's not actually very important at all.
  • Improbable Aiming Skills: With paper airplanes. He manages to get one to cook him eggs. Unfortunately, it doesn't stick the landing.
  • Incorruptible Pure Pureness: It's eventually revealed that he is pure good, since he is the Reincarnation of the Blue Catalyst Comet, which incarnated as a butterfly, a symbol of rebirth. His goodness extends to the point that he tries to beat his purity into others. This is noticeable in the episode "Goliad": when the golem that Princess Bubblegum created turns evil, what does she do to stop it? Make a new one with Finn's DNA instead of her own. The original tries to invoke We Can Rule Together, but because of the pureness, it refuses and sacrifices itself to stop the other. On another occasion, the Lich uses Finn's innocence against him to open up a portal to the multiverse by a means Finn thought would prevent it. Throughout the series, he also has helped countless characters. Despite his Blood Knight tendencies and Hot-Blooded moments, Finn is still a purely good person.
  • In a Single Bound: He pulls one off in "Mystery Train" when he jumps between two fast-moving trains.
  • In Touch with His Feminine Side: He's a cutie who openly shows his emotions and affections. He also spends the night with the Ice King in "Thank You". Downplayed though, since he's a Blood Knight who loves fighting, wrestling, adventuring, rescuing princesses, etc.
    • His instrument of choice is the traditionally feminine flute.
  • In-Universe Catharsis: In "Fionna and Cake", Finn has shown to have adopted a fairly unhealthy coping mechanism for dealing with his problems (re: Accepting Jake's death), which involves carelessly throwing himself into danger to distract him from his problems, which he tries to use on Simon to help him deal with his depressive rut. He even shrugs off a nasty series of back gashes given to him by a bear.
  • Inexplicably Awesome: Finn, besides his robot arm, has zero cybernetic or biological augmentations, while a pretty sizable chunk of humanity does, including his own mother. Despite his, he consistently seems to be a great deal stronger, faster, and tougher than most of humanity besides the explicitly superhuman Seekers, and even in that case they're not that much stronger than him. It's very telling that, as an adult, he's able to treat a mutant bear the size of a bus like a literal plaything.
  • Innocent Blue Eyes: According to Andy Ristaino, Finn's eyes are blue.
  • Innocently Insensitive: He refers to Fern as something even closer to him than a brother. Of course, this is because he was Finn up until he was turned into the Finn Sword, and still wants to be Finn.
  • Inter-Class Romance: Has romanced two princesses.
  • Interspecies Romance: So far he's crushed on a candy person (princess) and a girl made of flames. And in "Puhoy", he even married and had two children with a pillow-girl. Of course, seeing as how there aren't very many pure-bred humans left on Earth, he doesn't have a lot of choice in avoiding this.
    • It's unclear what Huntress Wizard is, but she's not human.
  • It Runs in the Family: Like his father, Finn often keeps up a cheerful demeanor no matter what kind of stuff is blowing up around him.
  • It's All About Me: Not at first, but he can be a typical self-absorbed teenager later on, especially when it comes to romance (Bubblegum isn't talking about sacrificing her love life with you, Finn). Self-obsession is one of the flaws that make him think he's a monster in "Don't Look".
  • It's All My Fault: Starts blaming himself for the state of Ooo during the Elementals miniseries, wondering if he subconsciously wanted Fern to fail at protecting the kingdom.
  • Jerkass Ball: A couple of episodes from season 5 showcase some of his more selfish, dishonorable traits: In "Jake Suit" he doesn't care that Jake gets hurt when he wears him as armor and tells him to toughen up then at the end of the episode he wears the 'Jake Suit' and jumps down a volcano hurting Jake and himself (of course it's more of an example of him holding the Idiot Ball then). And later in "Frost & Fire" and "Too Old", the former of which has him ruining his relationship with Flame Princess, and the latter lying to Jake in hopes of getting alone time with PB. It doesn't work.
  • Keet: Finn is hyperactive, joyful, and sometimes surprisingly tender-hearted, when he's not beating his enemies to a bloody pulp.
    • His ceaseless energy is used as a plot point in "Power Animal", where a society of malevolent gnomes kidnaps him and attempts to harness his energy for a machine they built which would allow them to essentially take over the world.
  • Kid Hero: 12 when the series starts, 17 when it ends.
  • Large Ham: Not just large, massive. He competes with a World of Ham and manages the impressive feat of being one of, if not the hammiest ham in the land of Ooo.
  • Last of His Kind: At first, it was assumed that Finn is the last human in Ooo. However, this later turns out not to be the case as it's revealed that Ice King used to be human, other humans (namely Betty) appear in the series and, in the Islands mini series, it's revealed that humanity is thriving in a series of distant islands.
  • Lightning Bruiser: Finn has been shown to excel in all types of combat within the series, plus he is quick to his feet & able to take a HUGE beating. He just destroys any foe that stands in his way.
  • Like Father, Like Son: Despite having never met them, or at least before he did meet them, Finn took a lot after his parents, at least on some level or another. He mostly takes after his mother who dedicated her life to helping and protecting people. While he has none of his father's Jerkass tendencies, Finn does have his sense of Adventure and the ability to turn problems into solutions, along with Martin's barefisted fighting skills.
  • Limited Wardrobe: Invoked a couple of times. For example, a plot point in "BMO Noire" and "Princess Potluck"note  is that he seems to only have one pair of socks, and in "Little Dude" he has to go slay (another!) evil bear if he wants a replacement hat.
  • Looking for Love in All the Wrong Places: Finn's romantic interests don't tend to work out well for him. It reaches the point that one interest admits that she likes him then follows up by saying they wouldn't work together, because of the reasons that she likes him in the first place!
    • Fortunately for those hoping for any hint of a happy romantic ending for the poor kid, he meets Huntress Wizard again and they decide to give dating a shot after all.
  • Love at First Punch: Finn developed his crush on Flame Princess after she smacked him in the face with her (burning) hand and nearly destroyed his house with her fire powers.
  • Love Hurts: Both princesses have caused him no small amount of emotional (and physical) hurt.
  • Love Makes You Dumb: He tells Flame Princess she has this effect on him.
    Finn: When I look at you, my brain gets all... stupid!
    • Several episodes ("Too Old", "The Red Throne") have even had Finn taking a ride on the Jerkass Ball as well because he put trying to impress girls ahead of actually thinking.

  • Made of Iron: The kid has survived battles against multitudes of monsters, cosmic horrors and falling into a volcano, the last of which he did for fun. Painfully subverted in the season 6 premiere, where he loses his right arm.
  • Major Injury Underreaction: In Reboot, when the grass vines take off the lower half of his right arm, all he has to say is "AH! m'arm!"
    • He barely reacted when he lost his original arm, as he was more in shock over his father caring so little for him and fleeing.
  • Manipulative Bastard: Downplayed. Finn has a manipulative-obsessive streak. His tendency to manipulate people to instigate conflict so he could resolve it (since he is The Hero) was explored in All the Little People and bit him in the ass in Frost & Fire.
  • Maybe Ever After: His relationship with Huntress Wizard is left open-ended after the finale, especially after "The Wild Hunt" and "Seventeen" established a relationship between the two. After all, she did give him her heart.
    • The Season 11 sequel comic implies that they're still together.
    • The status of their relationship in Distant Lands is a complete mystery, as the miniseries doesn't give any hints if they're still together or not.
    • Fionna and Cake implies they're still together.
  • Meaningful Name: "Finn" means "fair-haired." He's blond.
    • It can be also understood as related to the word "final", as in "the last".
    • And might also conjure comparisons to legendary Irish hero Finn McCool.
  • Mind over Matter: The flower growing from the stump of his right arm allows him to manifest a shapeshifting arm out of pure psychic energy as well as levitate large objects using what remains of the Grass Sword's magic.
  • Missing Mom: His biological mother is actually still alive, (sort of), and has been wishing for his return for years. It's the reason Susan was sent to Ooo in the first place.
  • Morality Chain: Finn may be the protagonist, but it becomes increasingly clear that he's also the Morality Chain to... damn near everyone else. He consciously takes on the role of turning Flame Princess good, but it's also strongly implied that without him Jake would still be a thief and conman, Princess Bubblegum might be much more of a Totalitarian Utilitarian, Marceline would be the psychopathic troll she likes to see herself as, and Ice King would be doing some seriously squicky things to Princesses.
    • He tried to be this to Fern during Season 8. He initially failed after Fern tried to kill him in "Three Buckets", but he does help Fern redeem himself during the series finale.
  • Morphic Resonance: It's implied Finn's reincarnations and alternate timeline selves are all destined to lose their right arms, to the point where after it happens to Finn he notes that - in retrospect - having two arms felt weird.
  • Motive Decay: In "Too Old," Finn focuses on flirting with Princess Bubblegum instead of focusing on the diplomatic mission, rescuing Lemonhope, or being a hero.
    • In "The Red Throne," Finn focuses on trying to get back with Flame Princess, ignoring the Fire Kingdom's tyrant problem.
  • Muggle Best Friend: To anything that isn't completely evil. It makes him slide towards All-Loving Hero.
    • Princess Bubblegum tends to show off her creations to him.
    • Marceline trusted only Finn with her Fries song.
    • Heck, even the Ice King seeks Finn out when he wants somebody to chat to.
  • Mundane Made Awesome - "ALGEBRAIC!"
    • "Mathematical!"
    • His hat.
  • Mysterious Past: A Zig-Zagged Trope. Finn does have a known and simple past in which he was Happily Adopted by Joshua and Margaret and raised to fight evil. But how he wound up where they found him and the whereabouts of any other humans were complete mysteries until the "Islands" mini-series.
  • The Napoleon: Downplayed; he's more short than Princess Bubblegum, but he has also a lot of moments when he acts like a Jerkass.
  • Neutral Good: In-universe assigned alignment in the comic series.
  • Nice Guy: Probably one of the nicest members of the cast.
  • Nice Job Breaking It, Hero:
    • Season 4 Finale. Congratulations, Finn. You've single-handedly released the Lich into The Multiverse.
    • In "Frost & Fire", his obsession to see Flame Princess and Ice King fighting almost causes Ice King's death and the destruction of Ice Kingdom, and also ends up hurting Flame Princess' feelings, leading to their breakup at the end of the episode. When the Ice King tells you that you blew it, you know you really blew it.
    • Taken to an extreme in the Season 6 opening two-parter. The plan to get Finn to meet his father gets Prismo killed and ends up freeing a whole bunch of cosmic criminals, which, sadly, includes his birth father.
  • The Noseless: He isn't drawn with a nose. The creators state that it's a mutation.
  • No-Sell: In "Flute Spell" he gains immunity to electricity.
  • Not Allowed to Grow Up: Averted. In fact, he grows up in real-time! He ages every year, according to the creators. Though he's only had one on-screen birthday from 12 to 13, his Twitter profile identifies him as 14 as of 11/2012. He claims to be 16 as of "The Comet," and is 17 as of, well, "Seventeen."
  • Our Founder: In the Grand Finale the ruins of a gigantic memorial statue and grave complex for Finn are shown 1000 years in the future, having been constructed directly outside of Marceline's/Shermy and Beth's cave on the Grass Lands. There's also fallen statue of either Jake or Jermaine as well, and the remains of a plaque that appears to read "Finn" and "Jermaine" nearby.
  • The Paragon: In "Freak City", Finn refuses to let any of the freaks lay down and let life kick them around. So instead, Finn kicks them around until they decide to stand up for themselves.
  • Parental Abandonment: Not only was had he lost his birth-parents from babyhood, it is heavily implied that his foster-parents, Joshua and Margaret, are also dead, leaving him with only Jake at 12. However, "Billy's Bucket List" reveals that Finn's biological father is still alive. As well as his mother in "Islands".
  • Parenthetical Swearing: He loves this trope.
    "Holy stuff!"
    "What the jug is that?
    "Dump that mess!''
    "Math this..."
  • Perma-Shave: Played for Laughs/explained in "All's Well That Rats Swell", as BMO plucks any growing facial hair out (to keep him looking forever young) before he wakes up.
  • Pint-Sized Powerhouse: Despite being just a boy, he's a full-fledged adventurer who can hold his own in most fights. He's even been known to put the hurt on beings many times his size and experience, especially when properly motivated.
  • Pretty Boy: His Gaia Online Alternate Universe self is this in the Adventure Time themed chance item, while his FusionFall self is a winsome Gonk.
  • Psychic Static: Even mentally he's a small erratic target. Especially mentally.
  • Psychoactive Powers: The grass sword responds to Finn's wishes and could modify itself to suit them if necessary. The flower remnant growing from the stump of his right arm does so as well. From levitating large objects to forming a shapeshifting psychic limb, it does whatever it can to grant its masters wishes.
  • Pungeon Master: He loves to drop puns.
    "I'm weddy for the wedding!"
    (pushing a zombie into the ground) "You're grounded, mister!"
    (blasting a pig with ice cream) "FREEZE TO MEET YOU!!"
  • Raised by Wolves: They were magic talking dogs, and they were as intelligent as humans. "Boom Boom Mountain" reveals Finn was orphaned as a baby and taken in by Jake's parents. Jake is explicitly his big brother.
  • Reincarnation: In "The Vault", Finn is revealed to have lived several past lives, including the ghost woman haunting him, who was a mercenary named Shoko. "The Comet" reveals that Finn was originally the blue Catalyst Comet, and has been reincarnating on Earth since it first crashed there, starting as a humble butterfly. "Come Along With Me" suggests he'll be given yet another life as a hyperactive tomcat named Shermy—complete with a descendent of Jake for a companion.
  • Reincarnation Friendship: It's shown that several of Finn's current relationships have spanned across multiple lifetimes in one way or another. His prior life Shoko had a companion in the form of a white tiger, a past incarnation of Jake's, and developed a close bond with Princess Bubblegum before Shoko's death, something that triggers Past-Life Memories in Finn prompting him to return the amulet Shoko stole. His future incarnation, Shermy, is close to one of Jake and Lady Rainicorn's descendants, Beth, who just so happens to also be Jake's reincarnation.
  • Revenge Before Reason: In the aftermath of the incident with his Dad, Finn comes to dislike all of his replacement arms and contemplates getting revenge on his Dad for the loss of his right arm. The flower coming out of Finn's remaining right arm grants his wish by giving him a phantom limb made out of pure telekinetic energy that allows him to move objects with his mind. Using this arm, he builds a tower to space with the intention of finding his Dad to rip off his arm as revenge for the loss of his own right arm. Princess Bubblegum notes that this plan is ridiculous and dangerous, but Finn continues it anyway.
  • Rhymes on a Dime: Has made up songs on the spot on several occasions, just for the heck of it. With his singing voice the effect is pretty rad.

  • Samaritan Syndrome:
    • In "Memories of Boom-Boom Mountain", Finn reveals his underlying drive to help everyone and everything with their problems because when he was a baby, he once went 'boom-boom' on a leaf and got stuck to it, and went unaided for hours until Jake's parents found him (and eventually adopted him). Finn helps people because someone helped him once.
    • Subverted on at least one occasion, where he mentions that he probably should help the Ice King, but he's too inexperienced and has no clue how to deal with the Ice King's issues. So he beats him up.
  • Screaming Warrior: Goes into this anytime he's in a fight.
  • Screams Like a Little Girl: On occasion, usually when he's startled.
  • She Is Not My Girlfriend: Regarding Princess Bubblegum. Jake even calls her his ex at one point.
  • Shipper on Deck: In "All the Little People", Finn finds sentient miniature AT characters and puts them all in crazy pairings. Even before this, he tells Jake that he thinks BMO and Ice King might make a good couple.
  • Signature Headgear: The iconic white hat he wears almost all the time, even while sleeping. He apparently skinned a bear to make it. As a baby.
    Finn: My... hat... is... AWESOME!!!
  • Singing Voice Dissonance: Throughout the series, he sings with an auto-tuned voice that supposedly comes from a tiny computer he swallowed at some earlier point. Subverted in 'What Was Missing', where he sings a heartfelt song to (and about) his True Companions Jake, Bubblegum and Marceline.
    • The Auto-tune singing returns in the Season 6 finale, though it appears to be a mix of this and his normal singing.
  • The Sleepless: Invokes it at least with the line "Justice never sleeps!" He does sleep regularly.
  • Species Surname: He's known as Finn the Human, mostly because dogs apparently don't have real surnames and he's the only pure human in all of Ooo, so he really is the human. It's eventually revealed his real surname is Mertens.
  • Star-Crossed Lovers: With Flame Princess as of "Hot to the Touch". Finn cannot touch her without getting hurt.
  • Stepford Smiler: He has his tendencies, placing traumatic memories "in the vault". After Jake's death, he tries to help a depressed Simon by punching the issues away. Even after he dies in "Together Again", Finn admits to Jake that he was never able to get over his death and secretly waited for his own so he can reunite with him, even though he did live a good life.
  • Stock Shōnen Hero: Deconstructed. At the series' start, Finn was a simple-minded yet righteous Kid Hero who lived to right wrongs and go on dangerous adventures. The problems started when he slowly came to see the Graying Morality of the world around him, and his impulsiveness bit him in the buns as he entered adolescence, leading him to make some really dumb moves and miss out on two Love Interests. While he's never stopped being a hero and fighting evil, he's a lot more of a mature Mellow Fellow, a sharp contrast to the early days when he was well known for his proud declaration of "I'll slay anything that's evil, that's my deal!"
  • Summon Magic: It takes him many hours to summon his spirit animals in "Still", but at least he gets a whole bunch of them and they're rather badass, for their species. Hunson is quicker to summon, but his allegiance remains in doubt.
  • Tagalong Kid: In "What Was Missing", Finn admits that he fears the others see him this way. An odd example, as he's arguably more proactive and competent than nearly everyone else in Ooo most of the time.
    Finn: Do you look down on me 'cuz I'm younger?
  • Token Human: Occasionally a plot point.
  • Too Kinky to Torture: Displayed prominently in "Jake Suit." In that episode, Jake is sick of Finn using him as a battle suit and seriously hurting him, so he does the same to Finn to get him to admit that it sucks. Unfortunately, even non-conventional forms of torture (getting Finn to read a boring book, embarrass himself in front of his girlfriend's family, etc.) prove ineffective, and when Jake decides to make Finn jump in a volcano, he's completely freaked out when Finn actually begs him to go through with it; as soon as Jake backs out, Finn uses Jake as a suit once again and jumps headfirst into the volcano for the hell of it.
  • Traumatic Haircut: Once had the side of his hair forcibly shaved off. He bemoans that his “style” is ruined. And in the next time he’s seen without his hat, he is shown to be bald, so he can redo his style.
  • True Companions: With Jake, emphasized by both family bonds and loyalty, and with Bubblegum to a slightly lesser extent. As characterization has developed, he may possibly also have this with Marceline, given how highly she regards friendship. All of them take some steps towards becoming True Companions in "What Was Missing", though with Jake being the Wild Card, and Marceline and PB not getting along very well, it takes some considerable effort on Finn's part.
  • Tritagonist: While still a main character he’s demoted to this in the Stakes miniseries with Marceline taking his place as the protagonist.
  • Unwitting Instigator of Doom: For all his heroic deeds, he likewise seems to have a habit of unknowingly causing just as many disasters. Up to reviving the Lich, being an indirect cause to Lincoln's death, giving the Lich what he needed to (nearly) take over the world, heck even trying to wish away the Lich wound up backfiring.
  • Vengeance Feels Empty: When Finn finally reaches his destination in "The Tower," he meets his dad and punches him out, only to realize that he can't bring himself to go through with tearing his arm off. Princess Bubblegum reveals that she dressed up as Finn's dad in order to let him relieve his stress regarding his personal issues with his Dad. Observing his expression she notes that his revenge probably didn't make him feel all that better. Finn agrees, and the next time he meets Martin, he's less angry than he is incredulous at how many levels in Jerkass the guy takes every day.
  • Vocal Evolution: In earlier seasons, his voice was much higher. As his voice actor went through puberty, his voice lowered, mirroring the series' gradual Cerebus Syndrome and Finn's growth in maturity.
  • Weaksauce Weakness: Finn's fear of the ocean, although he does get over this by the end of Season 5's "Billy's Bucket List", thanks to help from the Grass Sword. (He has a few others, but they are rare or unlikely to occur.)
  • We Are as Mayflies: Inverted - it's strongly implied that his canine adoptive family ages in dog years.
  • "Well Done, Son" Guy: He can only carry on if he knows his dad cares for him, as seen in "Dad's Dungeon". Eventually averted in the case of Finn's actual dad. Despite being initially devastated that Martin apparently didn't care about him, by "The Visitor", Finn realizes he's better off without a deadbeat like his dad.
  • What the Hell, Hero?: Delivers one to Bubblegum in "What Have You Done?" when she has the Ice King imprisoned despite him not doing anything wrong. Turns out she intended to beat pained cries out of him. True, it was to cure the Candy Kingdom of a plague he accidentally started, but it's still a bad thing to do because she wanted him to beat the Ice King up for nothing and her lack of communication. Finn and Jake call her out on it and she does seem to get a What Have I Done moment as a result.
    • Also, in "Frost & Fire", where Finn tricks Flame Princess and Ice King into fighting using her own private issues against her. Ice King even flat out states to Finn, "You blew it."
  • When All You Have Is a Hammer…: His response to the black hole he created?
    PB: You blew it, Finn! With this! [Shows bubble-blowing device]
    Finn: Then I'll kill it with this!
  • Why Did It Have to Be Snakes?: He's terrified of the ocean and only the ocean—not rivers, lakes, or puddles. He is also afraid of the body of water in question only if he consciously knows it's the ocean or not. Eventually it's revealed that this fear probably stems from him almost drowning in it as a newborn while stuck on a raft with his dad.
    • He's also scared of clowns. He especially hates the Clown Nurses.
  • Wise Beyond Their Years: Even at only 12 years old, Finn was a street-smart young boy with an ace in fighting off villains with fantasy swords and saving princesses.
  • With Great Power Comes Great Insanity: After putting on the Glasses of Nerdicon. Possibly subverted as he knew how everything would proceed, including the madness and subsequent removal of the glasses.
    • Any time he gets any sort of artifact of power it will quickly be taken away from him. ("Wizard", "Daddy's Little Monster", etc.)
  • Would Hit a Girl: Finn would hit anything. Except a princess. He's very uncomfortable punching princesses. However, that's not to say he's above hitting females in general. Just ask Marceline (who he punched in the face in "Evicted") and Me-Mow (who he bashed with a rock). He was also willing to fight Patience st. Pim (even if he never got a chance to).
  • You Can't Fight Fate: In every alternate universe shown so far, some event happens that makes Finn lose an arm. As of "Escape from the Citadel", Main!Finn lost his as well.
  • Zany Scheme: One day he may be the master of these. Other days he gets egg on his face (or Marceline's kitchen floor). Simply lifting Tree Trunks is insufficient—instead he has to out on thick layers of makeup first. And so on. Except for those times that he's Crazy Enough to Work it, or lumpified.