Adventure Time: Other Characters / Characters

Characters from other locations in Adventure Time.

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Humans

Humanity

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Everything stays...

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...but it still changes

A once populous species who prospered during the era before Ooo. The vast majority of humans were subsequently wiped out or mutated during the events of the Mushroom War and its chaotic aftermath. Despite this, they manage to persist even a thousand years after their civilization was destroyed. The mystery of their destruction and survival would serve as a major part of the show's backstory, including how Finn was for a long time assumed to be the last human in Ooo.

After the End: The Mushroom War wiped away their civilization and most of humanity with it. By the time of the series, the only known settlement of survivors are an isolationist island archipelago cut-off from the rest of the world.
Great Off Screen War: The Mushroom War, a conflict that resulted in the end of civilization, the near-extinction of humanity, and the eventual magical terraforming into the Land of Ooo. What caused the Mushroom War and how humanity got a hold of magical nuclear bombs and whatever weapon completely erased an entire chunk of the Earth is never made clear.
Humans Are Survivors: Nuclear war, vampires, Rainicorns, mutant monsters, magic, and the Lich and humanity still managed to narrowly escape total extinction.
Humanity's Wake: The ruins and relics of Pre-Mushroom War humanity can be found across the series.
To Serve Man: During the early aftermath of the Mushroom War, human survivors were hunted as food by both vampires and Rainicorns.
World War III: The Mushroom War which resulted in the destruction of old human civilization is heavily indicated to have been a global conflict involving nuclear weapons.

The Islands

People of the Islands

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The Islands refers to a secluded archipelago which is home to an isolationist but technologically advanced society of Humans descended from the survivors of the Mushroom War. They were founded by Two Bread Tom and his followers nearly a thousand years before the events of the show.

Defector from Decadence: The "Hiders" are people who try to escape the Island.
Fantastic Caste System: The human society on the Islands seems to have a some sort of caste system, although notably not every member of the Island society seems to be part of a caste. The three currently known castes are Experimenters^note, Seekers^note and Helpers^note
Hidden Elf Village: Highly isolationist and cut-off from the rest of the world since early in its foundation. To the point of creating Seekers and the Guardian to enforce this isolation by preventing any humans from leaving. They cease being this thanks to Finn; as they now allow people to leave and even establish a settlement in Ooo.
Humanity Is Advanced: Their level of technology far surpasses most of Ooo, with the possible exception of Princess Bubblegum.
Police State: Their society has a group of elite solders who drag any one attempting to leave off to re-education. Minerva replaces these with her fleet of robots, which initially seems to be even more controlling, but Finn convinces her to lighten off and allow people to leave.
Racial Remnant: The only society of non-mutated humans known to still exist in modern times. Both Finn and Martin originally came from the Islands. The only exceptions shown are those such as Simon, Marceline and Moe who all pre-date the Islands and survived so long via abnormal means.
Space Clothes: Human fashion during the show's present, particularly those on Founder's Island and Up-Ton tends towards the colorful and avant garde.

The Founders

Voiced by: Tom Kenny (Two Bread Tom)

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”To live by the light of the Founders.”

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“As humans, it's our duty to tell the tales, to sing the songs. Art must survive.”

A group of human survivors who lived during the early aftermath of the Mushroom War nearly a thousand years prior to the beginning of the series. They would eventually leave the land which would eventually come to be known as Ooo, going on to establish the Islands and its society. They were led by Two Bread Tom, and were able to survive long enough to leave Ooo due in large part to Marceline.

Ancestor Veneration: Due to being the original settlers of the Islands, much of modern humanity are likely their descendants. This connection does not prevent their apparent portrayal as deity-like figures.
Cult of Personality: The indoctrinated citizens of the Islands live by the “Founder’s Truth”, and Seekers-in-training are shown being taught about how the Founders are deity-like figures whose way is the only way for Humanity to survive.
Founder of the Kingdom: Exactly What It Says on the Tin. They are the group of human survivors who went on to form the basis of the society of the Islands.
Historical Hero Upgrade: Island propaganda makes them appear akin to all-knowing gods, a far contrast to the relatively normal survivors who Marceline protected. The Islands Graphic Novel indicated that the isolationist policies of their society were less to a result of infallible wisdom and instead a trauma-induced paranoia of Tom caused by his grief at Jo going missing while exploring the forest outside their settlement.
Our Founder: A statue of Two Bread Tom was built in a park located on Hub Island.
Small Role, Big Impact: Their only living appearance in the show was in flashbacks where they were simply shown as being a survivor group which Marceline befriended and protected. But the society they built would go into long out live them and eventually result in the birth of Finn the Human.

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Voiced by: Ava Acres

Jo (AKA Bunny Girl) is a young girl first appearing in the Stakes mini-series in which she befriends a younger Marceline. She later stars in the Adventure Time Islands Graphic Novel.

Action Girl: As she spends more time in the wilderness of Founders Island she learns how to survive and grows into an action girl.
Calling the Old Man Out: At the end of the Islands graphic novel she calls out Two Bread Tom on his extreme paranoia of the nature and wild life of the Island.
Nature Hero: Seems to have become one by the end of the Islands Graphic Novel.
Posthumous Character: Considering she was around almost a thousand years before the events of the show and is a normal human it's really likely that she is dead long before the time of the show.
What Happened to the Mouse?: So far we haven't learned what happens to her after the Islands Graphic Novel or what her ultimate fate is.

Alva

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Voiced by: Helena Mattsson

A human woman of Swedish descent at a scientific outpost on Back-to-Nature Island.

All Animals Are Domesticated: She's able to communicate with many of the creatures on her island, including a bear. Possibly due to some sort of non-intrusive technology.
Mistaken Identity: She thinks Finn is the one who drew the nice picture of Jake in his book, and is disappointed when he draws her badly.
Shrinking Violet: In the film she shows Finn, her younger self waves shyly at the camera, then blushes.
Sole Survivor: The other people at the base all died from the harsh climate and dangerous giant animals — which they caused in the first place.
The Unintelligible: She only speaks Swedish, though she does seem to start figuring out what Finn's saying, eventually.

Frieda

Voiced by: Jasika Nicole

A human "Experimenter" from the Islands.

Ambiguously Gay: There's significant room to interpret her Childhood Friendship with Kara as developing into something more. In particular, when Susan/Kara and Frieda ride off, Frieda is hugging Susan's neck from behind.
Fantastic Caste System: She's a member of caste of humans raised to be scientists.
I Just Want to Be Free: She's one of many humans who wants to leave the Islands, feeling they can't be free while they live there. Despite Kara being tasked with preventing escapes, Frieda gets her reluctant support in making a vehicle to ride out, but her attempted is crushed at the last second when Dr. Gross finds them and forces Susan to destroy her vehicle. Later on, a combination of re-education and being stuck for years has convinced her that wanting to leave was a bad idea. Susan and Finn eventually get her to remember what she wanted in the first place, and she becomes the first human to willingly move out of the Island.
More than Mind Control: After years of "re-education", Frieda lost her original adventurous spirit, saying that she only feels anger when she thinks about it. Susan and Finn help her snap out of this.

Minerva Campbell (SPOILERS)

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Voiced by: Sharon Horgan

Finn's mother, a human "Helper" from the Islands. She met Finn's father Martin after he was injured trying to escape. When Martin ran from attackers with Finn in tow, accidentally landing them both off the island, Minerva was so distraught that she rededicated herself to her work harder than ever. After a deadly virus outbreak leaves her terminally ill, Minerva uploaded herself into the Islands' computer, created an army of robotic version of herself to take care of everyone, and became the de facto ruler of the Islands.

Anti-Villain: Everything she does comes from a genuine desire to keep people happy and safe.
Back for the Finale:
- She (or more likely her Remote Body) comes with a boatload of humans to visit Ooo in the "Where Are They Now?" Epilogue.
- One of her robot bodies returns in Adventure Time: Fionna and Cake first patrolling Up-Ton in "Cake the Cat" and later returns in the last episode "Cheers" as Simon's therapist.
Big Bad: Of Islands. She's the one running the Islands, keeping anyone (especially Finn) from escaping.
Body Uploading: Dying from a plague, she irreversibly uploaded her entire body into a computer network.
Chronic Hero Syndrome: Her son got his natural urge to help people from her. She even went as far as to upload herself into a computer so she could keep taking care of everyone in Islands after her body died during a plague.
Clone Angst: Downplayed. Minerva admits that she isn't quite sure if she's "alive" and not just a digital copy of her original, now deceased self, but she feels like she is and hopes it's good enough.
Exhausted Eye Bags: Her tireless work as a doctor shows in the slight bags under her eyes.
Fantastic Caste System: She's born in the "Helper" cast, which consists of doctors and aid workers, and is very much into the role. Despite this, she seems to have eliminated the system herself, as the robots replace the visible function of Seekers and Helpers (the latter all having died) while Frieda has gone from an Experimenter to working at a toy shop.
Florence Nightingale Effect: She met Martin when he was in the hospital for two broken legs and she was his nurse. They started dating after she took pity on him and saved him from being taken to re-education.
Foil:
- To Finn. They enjoy their work in helping others who are in need, which both can do in extreme methods. Finn takes his method of physical helping violently so long as evil is the only one trampled across his path, Minerva helps people exceptionally but peered close enough to doom her people nearly twice in her choices.
- To Princess Bubblegum. They both shown their work to Finn on how they operate their respective colonies scientifically. Bubblegum is able to let go of her totalitarian approach with Marceline's help, while Minerva is still plagued by the thought of her husband abandoning her along with her own child only for said child help her in getting a hold of herself.
- To Martin. Martin was a self serving sociopath who only ever cared about himself, while Minerva is empathetic to the point that she made her entire existence about helping others. Neither of them are shown to be well adjusted individuals though for very different reasons.
Follow in My Footsteps: She finally see her son as something other than a child to be kept safe when she finds out Finn grew up to be a "helper" like her.
Generation Xerox: Her character design is not only as similar as Finn's, they are just as helpful to the people around them, just in different methods.
Hair of Gold, Heart of Gold: Just like her son, Minerva has blonde hair and is a good-hearted person who wants to do nothing more than help people. It's true her methods can be pretty extreme, but Minerva ultimately means well.
Heel–Face Turn: After seeing Finn's desire and acts to help people despite growing up in Ooo, she decides maybe the outside isn't so terrible and that people should be able to leave if they want.
Horrible Judge of Character: She fell for Martin even though she knew he was manipulative and even explained how he'd take advantage of her before doing so. It's highly ambiguous whether she made him a better person (at least temporarily) or was just a naive do-gooder exploited by a con man.
Knight Templar Parent: She attempts to force her son into uploading his consciousness to the internet for his safety. Her Establishing Character Moment even shows shades of My Beloved Smother.
Miverva: But that doesn't matter anymore! You can stay here, with me!
Finn: Oh, I don't think that's necess— (Miverva-Bot clutches onto Finn)
Miverva: For the rest of your life.
Last of Her Kind: Unless you count Finn, she's the last Helper after the rest were killed treating a plague. If you consider her to be alive.
Light Is Not Good: She is a sincerely well-intentioned person, but very on the totalitarian side of things until Finn convinces her otherwise. Her light cloud outright eradicates free will.
Light 'em Up: By proxy. Thanks to now being an AI she can control a "light cloud".
Like Parent, Like Child: Minerva and Finn both dedicate their lives to helping people, though Minerva takes this much further.
Like Parent, Unlike Child: Despite having the same core goal, her and her son's methods are complete opposite: Finn tries to protect people by fighting evil, sometimes to the point of being excessively violent. Minerva tries to take care of people to the point of coddling them.
Logical Latecomer: She's lived in a Hidden Elf Village all her life, and considers what Finn shows her of the rest of Ooo not just dangerous but also bizarre.
Minerva: Your world seems so chaotic. Your ruler is a piece of gum, your friend's a vampire, you dated a bit of fire—Your life is constantly in danger!
Loved by All: As a doctor, she was so trusted that people believed what they knew was complete nonsense just because she said it.
Meaningful Name: Shares her name with the Roman goddess of wisdom and medicine.
Missing Mom: She was separated from Finn when he was a baby and he never got to meet her until their encounter in Islands.
My Beloved Smother: When she finds out Finn is alive and came to the Island, she insists he can't leave, even though he has a whole life outside. This character trait of hers extend to everyone on the island, with robots in her visage monitoring everyone for any sign of danger or dissidence. When Finn manages to convince the humans that life outside the Islands is a good thing, Minerva tries to forcibly upload everyone on the islands into the digital database.
Nice Girl: She's overprotective, but other than that's she's a helpful and well-intentioned person.
Not Even Bothering with the Accent: Her voice actor uses her natural Irish accent, which no one else on the Islands has.
Opposites Attract: A tireless, trusting, over-protective doctor who fell in love with a lazy, two-siding, self-serving conman.
Pro-Human Transhuman: She converted herself to a digital lifeform to keep helping people even after her body gave out.
Sanity Slippage: It's clear that losing Finn took a heavy toll on her psyche and dealing with a lethal virus that wiped out all of the helpers pretty much finished the job that started. All of her actions in the present are very realistically shown as not sane ones.
Totalitarian Utilitarian: She makes sure everyone on the Island is happy and safe, never letting them experience anything else in life. When many people show signs of wishing to leave, she tries to forcibly upload them into the computer so they can never leave.
Walking Spoiler: The fact Finn's mother is alive one of the first major twists of Islands. That she's the Big Bad of the arc is another.
Well-Intentioned Extremist: Her treatment of Finn aside, she also tries to keep the residents of the Islands safe by ensuring they never leave, but in doing so, she's crippled them developmentally and they have a difficult time making their own decisions and when she notices that they start to consider to leave the Islands, she tries to forcibly upload them into the computer.

Other Humans

Martin Mertens

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Here comes the rascal!

Voiced by: Stephen Root

Finn's father, trapped on the Citadel for unexplained reasons. He's freed during "Escape from the Citadel".

Abusive Parents: In addition to his complete apathy towards Finn's existence within minutes of meeting him, he manipulates his son into healing him, immediately ditches him, and constantly attempts to use him to further his own goals. There are a little bit of hints that he cares for Finn, but they are buried behind Martin's selfishness. Ironically, it was shown in the past that Martin was a very protective dad.
Alliterative Name: Martin Mertens.
Ambiguous Situation: Whether Martin's jerkass behavior in the present is a result of his head injury and memory issues or him simply choosing to burn bridges after he believed his son died and returning to old behavior is ultimately up to the viewer to decide.
Archnemesis Dad: He's the first person that Finn wanted Revenge against and got away with it. In result, Finn's hatred for him burns so deep that Finn can easily sing a sweet, calming lullaby about ripping Martin's arm off without batting an eye. Eventually, though, Finn let go of the hatred toward his dad and is fairly neutral if not exasperated or confused by him.
Ascended to a Higher Plane of Existence: Takes up the Catalyst Comet's offer to transform him into a "new mode of existence." In "Prismo the Wishmaster", he's briefly seen on Scarab's list of cosmic fugitives (wanted for desertion), implying he became a cosmic entity.
Believing Their Own Lies: Martin seems to genuinely think himself a great person, once claiming a run of luck was "the Globs rewarding me for my heroism" when there was no one else around for him to deceive.
Beware the Silly Ones: Implied. He's incredibly cheery in his one appearance, and seems incredibly affable, and might even be likable if not for his actions during said first appearance... until you consider that he's in a cosmic prison full of incredible monsters up to and including The Lich, and a group of said monsters instantly accept him as their leader with no argument. And of those criminals, he was the only one not to be placed under the Lich's control. Whatever he is or however he got there, there's definitely more to him than it seems.
Broken Pedestal: The apple falls far from the tree, to say the least.
Con Man: He's been one his entire life and it shows.
Consummate Liar: He lies constantly without breaking a sweat.
Crouching Moron, Hidden Badass: He may be a Dirty Coward and Manchild, but he's just as agile and good at fighting as his son.
Daddy Had a Good Reason for Abandoning You: Played with. Back then in the Island, Martin didn't intentionally abandon Finn; he took Finn with him while running from people out for blood, planned to escape by circling around the Island in a boat, and was separated after they ran into the Colossus, with Martin still trying to stay with Finn despite FIGHTING the Colossus, and only finally relenting when his only option became fleeing. Still, the situation was caused by Martin's own actions coming back to haunt him.
Dark and Troubled Past: Implies this in "The Comet" when Finn calls him on his abandonment tendencies, saying that he keeps leaving because he has nothing to return for.
Dirty Coward: His first instinct is always to save his own (worthless) skin, and only his.
Disappeared Dad: He abandoned Finn when he was a baby. In the Citadel he refuses to give him any real explanation, then abandons him again. He seems to be actively avoiding him for some reason. Turns out Islands clarifies that said abandonment occurred in his attempt to save Finn.
Dissonant Serenity: Has a rather cheery disposition despite apparently being one of the most dangerous criminals in the universe. He talks in a very casual tone as he is being pursued by the prison guards at the Citadel, shows the barest minimum of pain at a serious injury dealt to his leg, walks up to bad guys (and becomes their new leader) and exchanges pleasantries with them like it was nothing, and gives two notable winks that disarm the people they're aimed at and get them to follow his orders.
The Dragon: He acts as an accomplice to Hugo's plan in "BMO".
Even Evil Has Loved Ones: Averted or at best Played with. While Martin isn't entirely without affection for his son, Finn, as shown by how the resemblance causes him to warm up to Martin 2, he is only willing to help him when it is convenient for himself. Also, see In Love with the Mark.
Establishing Character Moment: His very first actions upon being partially freed by the Lich is to convince Finn and Jake them to free him completely, and then ask them for a spaceship, only reacting in surprise that they don't have a ship rather than the fact Finn's his long lost son. This highlights just how selfish and self-serving the man really is, and that's before we get to the fact Martin soon ditched Finn to save his own hide at the first possible opportunity.
Fat Bastard: He's overweight and a complete deadbeat that has zero desire to reunite with his son.
Faux Affably Evil: Despite his cheery disposition, his true motivations are unknown, he's apparently a cosmic criminal, and he'll screw over someone who just helped him out without a second thought.
Flipping the Bird: On Martin's mugshot picture shown in Scarab's list of cosmic criminals, Martin is flipping both of his middle fingers at the camera.
The Fog of Ages:
- Martin has memory issues, which he puts down to his incarceration in the Citadel as he had no way of keeping track of time so his recollections are skewed.
- In Islands it's implied that most of Martin's negative traits in the present are due to a head injury he received saving Finn. In the human colony on the islands he was always a shiftless con man, but he never actually killed anyone. We see him falling in love with Finn's mom Minerva, a doctor, and they genuinely seemed to have a loving relationship in the first months of Finn's life. He apparently fell In Love with the Mark, and seems to have been genuinely interested in raising Finn with her. Then he had to bail when enemies from his shifty past caught up with him, and while escaping on a raft the islands' robo-guardian attacked. He bravely left the raft to fend it off while explicitly promising Finn he'd come back for him, but the resulting explosion knocked him into the sea. 15 odd years later, Martin can't even remember any of his former life very clearly. It's Simon Petrikov/Ice King all over again.
Foil:
- He and Finn are opposite in personality and even wardrobe. They also have differing philosophies as of the season six finale. Finn grows to believe everything has a purpose while Martin sees the universe as having no purpose (it's unknown if this leans more toward Straw Nihilist or Anti-Nihilist, but given his cheery state and his neutral stance, most likely the latter. See Hidden Depths below for more details.) Flashbacks in the Islands miniseries furthers demonstrate their differences. Finn has his moments of selfishness while ultimately remaining a good person, while Martin demonstrates moments of heroism before relapsing into his typical It's All About Me behavior, though it's heavily implied that it was due to suffering brain damage and memory loss.
- To Simon. They were both father figures (Actual father in Martin's case) to mostly human people who found their way onto OOO. While Simon was a good person who ended up being turned into a crazed husk of his former self thanks to acts of protection for Marceline, Martin had some development into a good person coming for him that got interrupted and discarded all together thanks to an act of protection for Finn. Their significant others were also central to their development, with Simon finding Evergreen's crown and incidentally starting his path to insanity because he wanted to show it to Betty, and Minerva being the first person other than himself that Martin cared about and the key to his development into a better person. In current times, the Ice King is a powerful but mentally unstable wizard with blue skin and a blue robe, while Martin is a normal if amoral person with a red outfit, ironically being the blue oni to Ice King's red oni. Also, while Ice King was a recurring enemy early on in the series who developed into an ally and friend to the heroes overtime, Martin did actively look out for Finn prior to his head injury, but didn't give Finn any paternal care in the present day, outright tearing his arm off by accident and never offering Finn an apology. Their fates by the show's end are also opposed, with Martin choosing to become a being higher than mortality and Simon being reverted to his primal state as a normal human being thanks to GOLB.
The Greatest Story Never Told: As Islands reveals, Martin left with Finn not to kidnap him or anything malicious, but because the consequences of his past were catching up to him and during his brief escape with Finn, he fully intended to tell Minerva he was coming back, only for the Guardian Entity to show up and attack them due to thinking they were leaving. Martin promised Finn he'd be back for him before jumping off to successfully injure the entity, but the resulting explosion injured Martin and sent Finn to the shores of Ooo. Because it is impossible to have witnesses for this, Minerva and Finn believe that he simply took Finn for reasons unknown and then abandoned him.
Hate Sink:
- Those who were expecting Finn's dad to be a cool guy will be disappointed. And unlike some of the show's other most despicable people who could at least appear cool, Martin is just a fantastical version of the self-absorbed deadbeat dad.
- Subverted in "Islands Part 5" where he's more of a Lovable Rogue instead of the deadbeat jerkass we know, and it shows that he genuinely cared about Finn when he was an infant, going as far as to attacking the Colossus to protect Finn and implying that his jerkass side was born out of this moment.
Martin: I'll be back for ya.
Heel–Face Door-Slam: Martin seemed on his way to becoming a better person during his time with Minerva, even making an honest living as a barber, but after getting separated from Founder's Island, being unable to return to his son or Minerva and suffering a head injury, he seemed to go back to his old, dishonest ways.
Hidden Depths: While it's not Jerk with a Heart of Gold levels, there is some part of Martin that does genuinely care about people, hence him saving Finn's life in "The Comet". He also was willing to sacrifice himself to offer Martin 2 a chance to escape, but when that didn't go as planned, was content to leave Martin 2 to his fate. He also admits to Finn that talking about Minerva stresses him out, implying that deep down he feels guilt for abandoning his family.
In Love with the Mark:
- It's heavily implied that Martin was genuinely turning his life around for Minerva, and was by all accounts shown to greatly care about Finn.
- The name of the small ship he has is "The Minnie," indicating she at least held a place in his thoughts.
Irony: His last interaction with Finn his son is accepting Martin will never change. Both parties seemingly ignorant that Martin had changed immensely 16 years earlier for both Minerva and his son.
Jerkass: He cares only for himself and his own immediate benefit, and doesn't even evince much awareness that he could be expected to care about his son or the other people he manipulates.
Jerk with a Heart of Gold: It turns out there really was a positive side at one point, which he seemed to tragically lose from a couple of things that he actually didn't have a choice over. This could probably explain him being a Karma Houdini.
Jerk with a Heart of Jerk: Every time it seems he might be revealing a positive side to himself, it turns out to be some lie or trick to further benefit himself. He really is that much of a selfish asshole. Though later on, it's implied that he simply Took a Level in Jerkass when his bad memory made him forget that he wasn't always like this.
Karma Houdini: After all he did, he gets to ascend to another mode of existence along with the Catalyst Comet. Though it's later implied to be an unintentional redemption as his act of leaving the current reality for a new one enables Finn to finally let go of his grievances against Martin, accepting he'll never change.
Lack of Empathy: In "The Visitor", Martin tricks a village of tiny people into helping him (they actually aren't fooled and are just doing him a favor), nonchalantly talking about how taking advantages of them is driving them to starvation.
Manchild: Finn thinks of him as a child stuck in an adult's body.
Manipulative Bastard: In his first appearance alone, he cons Finn into helping him escape The Citadel without answering any of his questions. He outright tells Minerva that he'd try to look pathetic to get her to save him and may or may not have used that exact trick on her just a few minutes later.
Major Injury Underreaction: Martin gets the skin on his right leg sheered off by a laser, all the way down to the bone. Sure enough, he treats it like an injury that needs to be dealt with, but he shows the barest minimum reaction to it; at best saying "this really stings", rather than screaming bloody murder at how painful it is like most people would. Even taking into account the Guardian Blood, that he gets Finn to apply to his wounded leg, restoring the flesh to his bone, Martin's casual reaction to the wound is rather astounding.
Mysterious Past: Very. For starters, as one of the last (pure bred, as many of the current inhabitants are implied to be the mutated descendants of humans) humans on Earth what group of survivors did he come from? Is that group still around? What kind of life did he lead prior to having Finn? Who was the mother of Finn and how did he meet her? Was he missing because he was sealed away, or did he abandon him before that? Is he truly a cosmic criminal or was it some kind of frameup or misunderstanding? How exactly did Billy know that Martin was Finn's dad? And how did he know that Martin was imprisoned on the Citadel? Half of these are answered with the Islands mini-series.
No Good Deed Goes Unpunished: It's implied that his successful attempt to save Finn from the Island's Guardian is the event that led to him becoming a jerkass deadbeat father as a result of brain damage he took from it.
Noodle Incident:
- Just how someone like Martin wound up in a cosmic prison that's designed for Eldritch Abominations, including the Lich, is never touched upon.
- Somehow, he became an interplanetary criminal before that, even helping Hugo con the citizens of The Drift under the identity of Mr. M.
- Early on it was going to be implied that Billy himself pushed Martin into the Citadel while being fully aware that Martin was Finn's father, but this also would've raised questions a lot.
Never My Fault:
- When Finn finally asks why he was left in the forest, Martin gets incredibly defensive and suggests that "maybe you abandoned me, did you ever think of that?!" — Finn was a toddler, and this seems to prove to him that Martin might not be such a good guy after all.
- That said, it's shown that his memory is utterly scrambled and the truth is that he in fact never intended to leave Finn even when he was pursued by his past enemies and only ended up unintentionally abandoning him when he fought off the Guardian and got knocked into the sea in the proccess while suffering brain damage.
Screw This, I'm Outta Here: The moment he sees the Lich at the Citadel, he bails before things get real.
The Sociopath: Martin shows some extremely sociopathic behavior: he has a false charm which his actions constantly betray. He lies, manipulates, and otherwise uses people to his own benefit without any concern or empathy toward them, and cares about only himself and nobody else. Through it all he still tries to justify his actions with the most blatantly trivial excuses.
Took a Level in Jerkass: It's revealed in Islands that Martin was a Lovable Rogue rather than a huge jerkass, but after certain events happen, Martin becomes much worse than he ever was in the past.
Ungrateful Bastard: He uses Finn to heal his leg and then completely ditches him for the Citadel inmates.
Unreliable Expositor: What little details he's given about how he got separated from Finn should be taken with a grain of salt. He claims Finn was born on a banana boat and that he himself made some kind of choice to leave earth while they were on it. He was right to some extent but it's implied that his injuries from the fight with the Island Guardian left his memory messed up enough that even he is unsure about what he's saying.
The Unreveal: It's never revealed what his cosmic crime was, or how he figured out how to get into space in the first place.
Walking Spoiler: He's Finn's father, for crying out loud.

Deities and Cosmic Beings

In General

Arc Symbol:
- Red four-sided pyramids (or diamonds when viewed from the top) appear to have some sort of unspecified significance and show up most prominently on top of GOLB's head, on the top and bottom of Grob, Gob, Glob and Grod's helmet and Scarab's mask.
- "The boss" is represented by a golden cord phone with angel and devil wings and two stars on the back.
Celestial Bureaucracy: An especially corrupt and dysfunctional one. Gods regularly neglect their duties or abandon their posts altogether, give special treatment to mortals they like, hold vendettas, engage in practices like nepotism and sometimes even try overthrowing each other. It's so bad the system has to employ "god-auditors" whose sole responsibilities are keeping other gods in line and even then they can be just as corrupt like Scarab when he shirks his duties to pursue Fionna, Cake and Simon in order to take Prismo's position as Wishmaster. The Top God in charge is Prismo, Scarab and Orbo's mysterious boss.
Cosmic Entity: They are this and nearly everything under both it and all Tropes of the Divine.
God Job: Most entities are assigned one as a given task to fulfill.

King Man/Normal Man/Magic Man

https://static.tvtropes.org/pmwiki/pub/images/kingman_adventuretime.png

^{Click here to see him as Normal Man}

^{Click here to see him as Magic Man.}

Voiced by: Tom Kenny

A mysterious alien from Mars. He was exiled after performing many magical pranks on the Martian people, in the hopes that he would learn how to care for others again, but instead spent two hundred years bumming around Earth being a jerk to everyone in Ooo. Fortunately, he changes his ways after Betty steals his magic powers, and spends the rest of the show ruling wisely to atone for his crimes against Mars.

The Atoner: He spends all of "Normal Man" attempting to make up for all of his past misdeeds as Magic Man.
Ax-Crazy: As the Magic Man, he was an absolutely sadistic maniac who amused himself by doing horrible things to others with his magic, and he did so with clear jovial glee.
Bright Is Not Good: As Magic Man. Especially when shedding his hobo outfit. Averted after his Heel–Face Turn
Brought Down to Normal: As of "You Forgot Your Floaties".
Card-Carrying Jerkass: The guy REALLY likes to let people know he's an incredible jerk, AND PROUD OF IT!
Despair Event Horizon: Margles death, as well as the destruction of his Replacement Goldfish in M.A.R.G.L.E.S., was what would drive Magic Man to becoming a crazed jerkass.
Face–Heel Turn: Flashbacks show that he was a pretty decent guy before Margles' death caused him to lose his mind.
For the Evulz: Seems to be his M.O. His entire reason for making everyone miserable, even the people who pay him kindness, is to teach them that he is an incredible jerk.
Freudian Excuse: In "Sons of Mars" it is shown that he used to be a decent guy with a loving wife named Margles until GOLB "took her away", presumably killing her. As shown in "You Forgot Your Floaties", Magic Man created a new "defense system" named M.A.R.G.L.E.S. in the image of his wife, which failed and ended up falling into Olympus Mons, which is what is seen in the "Sons of Mars" production artwork. Doubles as Love Makes You Evil And Crazy.
Glass Cannon: He IS very powerful, but the two times Finn and company have actually got their hands on him, it's shown he can't really take a punch as well as the other characters or recover as fast.
The Good King: Became this by the end of "Normal Man".
Heel–Face Turn: After losing his magic powers, he decides to atone for all the bad things he did.
Heel–Face Revolving Door: Unfortunately, Betty's offer to bring Margles back from the maw of GOLB lead to him abandoning Mars again. He was the first to tell the heroes of his and Betty's mistake after Maja exploded, and he would later return to Mars as it's king once again.
Hidden Depths: "Sons of Mars" hints that there's a lot more to his character than he lets on.
Jerkass: Everyone thinks he's a jerk, and he even admits it. When he loses his magic powers, though, he loses his jerkassery as well. Averted after taking a level in kindness.
Karma Houdini: "I win again, just like always!"
- Averted in "Time Sandwich" when he finally gets what's coming to him when he messes with Jake.
- Also averted once he becomes Normal Man. Because of his actions in literally every prior appearance, Finn and Jake knock him out with a frying pan on sight. Unfortunately, this time, he actually needed their help.
Lack of Empathy: He was banished from Mars to Earth until he could learn how to feel for others again. The only problem is he spent the whole time being a jerk to the people of Ooo. He does get over this after losing his magic powers.
Large Ham: "MAGIC MAAAAAAN"
Laser-Guided Karma:
- The first thing Finn and Jake do after returning to Earth from Mars is knock Magic Man unconscious with a single punch.
- He's also on the end of one hell of a beatdown at the end of "Time Sandwich". First, Jake gets his sandwich back, then Marceline elbows him in the face and then BMO runs him over with his skateboard.
Laughably Evil: Despite being a sadistic psycho, he's very hammy and likes to sing.
Meaningful Appearance:
- Going from Magic Man to Normal Man, the torn shirt and brightly-colored outfit he'd worn since his first appearance was swapped out for a clean collared shirt and muted tones, losing his pointy yellow hat as well.
- Becoming King Man brought forth a new outfit of a light peach robe and red cape with a golden brooch. He also acquired a top hat, reminiscent of Abraham Lincoln's.
Meaningful Rename: Calls himself Normal Man after being Brought Down to Normal. He later renames himself King Man after becoming Mars's new king.
Morality Chain: His dead wife is heavily implied to have been this for him.
Nice Guy:
- As Normal Man he is totally helpfully and regrets all the rotten things he did as Magic man.
- This continues when he becomes King Man as he proved to be a decent ruler and is well liked by the people of Mars.
Non-Answer: This gem.
Finn: So, how long have you had this house for?
Magic Man: Yes, that is true!
Oh, Crap!: When Jake figures out his riddle, his eyes widen for the first time in the series.
Reality Warper: Had this ability up until "You Forgot Your Floaties."
Sadist: As Magic Man, he really enjoys torturing other beings.
Sarcasm Mode: Except not always. In "Normal Man" he's shown to be sincere, not that Tiny Manticore buys it.
Tiny Manticore: Why do you sound so insincere?
Normal Man: That's just my voice.
Squishy Wizard: He was one of the most powerful magic users in Ooo as Magic Man, but could be taken out by a single punch from Finn.
Stepford Smiler: Until "You Forgot Your Floaties", Magic Man was implied to have deep-seated depression over Margle's death, though he masked it with child-like jerkassery.
Straw Nihilist: Up until his Heel–Face Turn, Magic Man accused the heroes (rightfully) of only acting like heroes so that they could get what they want, and that still wasn't his lesson.
Taking Up the Mantle: While his character and reconciliation as Normal Man is already unexpected, at the near end of the Elements mini-series, has him in possession of Abraham Lincoln's hat and his older brother's staff. Both strongly implying that he worked up his way of atonement to become the new ruler of Mars.
Took a Level in Kindness: After losing his magic and regaining his sanity, he became much more empathetic and now rules Mars as a benevolent king. He even reunites Jake with Finn and attempts to help Betty with her issues in "Temple of Mars".
Troll: He really enjoys pissing "sissy do gooders" off.
Wants to Be Hated: As Magic Man, this was his reason for living.
With Great Power Comes Great Insanity: On top of losing Margles, his dabbling in magic caused him to lose his mind and pretty much erased his moral compass.
Woobie, Destroyer of Worlds: He has a very tragic reason for his psychopathic behavior. See Freudian Excuse for more details.

Prismo

Voiced by: Kumail Nanjiani (original series), Sean Rohani (Adventure Time: Fionna and Cake)

An all-powerful being who resides in the center of the multiverse. He's close friends with the Cosmic Owl, and has the power to grant wishes (with a twist) to anyone who reaches him, and alter the course of time itself at will. He is the product of an old man's dream, who keeps Prismo alive as long as he's asleep. However, the Lich kills his corporeal body in "Wake Up," ultimately killing Prismo as well. This did not stop him for long as he used a time paradox to return.

He's later revealed to be the true creator of the Fionna and Cake universe, having stored it away in Ice King's mind for safekeeping due to it being "unauthorized". These actions would come back to haunt Prismo during the events of Adventure Time: Fionna and Cake when Scarab, a God Auditor, threatens to use it to usurp him as Wishmaster upon finding out about it.

Always a Bigger Fish: Despite being a very powerful entity, Crossover reveals that he does have someone he needs to answer to if something major (like the Space-Time Continnum being destroyed) happens. Considering what Prismo can already do and given what it might take to piss Prismo's boss off, that says a frightening amount of how powerful they must be.
Prismo: Now if that happens, my boss- let me repeat that, MY. BOSS. will hold me responsible. And by proxy, we all in hot water.
Ambiguously Gay: Prismo's pink-colored, he talks with a slight lisp, and he tends to chill in a hot tub with his guy-friends Jake and the Cosmic Owl. One topic of discussion in his room is him finding a girlfriend, which he awkwardly hems and haws over. He is also overjoyed when Jake casually claims he loves him and is very clearly deeply attached to Jake despite only meeting him recently. He's also very depressed after Jake's passing, complete with stubble and eyebags.
Back from the Dead: He came up with a plan to bring himself back should he ever die, involving Finn and Jake. After Jake eats the last pickle Prismo made, he's sent to a weird place that seems to be outside time. A time double of Jake becomes the new dream host for Prismo.
Badass Adorable: He's unbelievably sweet, but he can alter reality and grant a potentially infinite number of wishes of any kind to anybody.
Beard of Sorrow: His depression after Jake's death is marked by him gaining stubble.
Be Careful What You Wish For: Prismo warns Jake that the wishes he grants all have an ironic twist to them, unless the request is specific enough that there is no way for it to backfire against the wisher. For example, when Finn wishes that the Lich never existed, the result is an alternate timeline where the Lich never existed, but another, practically identical entity did.
Because You Were Nice to Me:
- A variant in that he admitted that part of the reason he helped Jake was that he greatly appreciated Jake actively being friendly to him as his only other friend seems to be the Cosmic Owl.
- This extends to Finn as he was willing to risk himself to help Finn meet his dad.
Benevolent Boss: Fionna and Cake ends with the Scarab, who imprisoned him in a cube in his own hot tub, under his employ as a janitor. Despite all of that, he's nice enough to put in a good word for him so he doesn't get a worse sentence, and even lets him take a break so he can check out his character creation tool.
Benevolent Genie: He's nice to an almost absurd degree. How nice? He straight out tells Jake not to waste his one wish on something stupid, like a sandwich, as well as explaining the fact that despite all of Prismo's power, he's still bound to giving wishes that have an "ironic twist". Heck, he even very heavily hints at the proper wish Jake should make to fix the whole mess made with Finn's wish.
Cheated Angle: He's almost always in profile but that seems to be by choice. He can turn his head despite his one-dimensional appearance.
Confirmed Bachelor: He tells Jake that he prefers the single life because relationships require too many compromises, using the question of coordinating dinner plans as an example. Jake disagrees and says that he needs to find Prismo a girlfriend, although Prismo seems more interested in Jake's company than anyone else's.
Could Say It, But...: He stretches this trope about as far as it goes.
Demiurge Archetype: Prismo is not the absolute supreme being but he is the primary agent of creation in the multiverse. He makes new universes to suit the wishes of people that meet him and his domain is what allows the passage of time throughout all realities.
Didn't Think This Through:
- He tried to help Finn with meeting his father by having the heroes bring his mortal body into the chamber, with the Lich in the room the entire time.
- Creating the Fionna and Cake reality was a bigger one. He wasn't supposed to create anything for himself, and dumped the universe into the Ice King's brain to hide it. The problems started when the Ice King was depowered into Simon Petrikov, rendering what was a magical world a relatively droll, everyday place as the magic went away. Then Fionna and Cake found the means to leave that world for Ooo, culminating in him accidentally confessing to Scarab he had made an unauthorized universe.
Dream Apocalypse: The wish-granting genie is really the dream of the real and relatively normal man. Waking him up destroys the Wishmaster form, a crime worthy of the Citadel.
Even More Omnipotent: Despite being described as "all-powerful", there are cosmic entities which exceed even his power, such as GOLB, and he mentions that he answers to a more powerful entity.
Fatal Flaw: A bit of a different version as his flaw isn't necessarily "bad": arguably, he's too nice and trusting to people, possibly caused from his isolation from society and desire for friends. Allowing himself to temporarily die (and later permanently die) for someone he's only known for a little while exemplifies this.
Good Is Not Nice: He matter-of-factly orders Fionna and Cake to return to the mundane world for their own safety even though he knows they are unhappy there.
Honor Before Reason: He'll grant one wish to anybody who visits him no matter what it is — something the Lich used to his advantage.
Hypocrite:He calls out Simon for his grief over Betty to the point of casting a Summoning ritual to bring her back which led to Fionna and Cake being summoned instead. But he is in no position to criticize Simon considering he clearly never got over Jake's death which led to his work performance suffering greatly, messing up Wishes and ignoring calls.
Jackass Genie: While he is usually rather literal with wishes, when Wyatt says he wishes it was quieter so he could think out his actual wish, Prismo immediately takes the opportunity to teleport Wyatt into a silent film-styled universe where Wyatt nearly gets run over by a train.
Literal Genie: Played with. The wishes executed act like this in nature, but he admits that he doesn't do it deliberately because it is out of his control. Careful, specific wording can get around the Be Careful What You Wish For part, and although he granted The Lich's wish as it was, he's nice enough to help Jake to wish for the right thing and screw The Lich over.
Living Dream: He is an entity born from the dreams of an elderly man.
Living Shadow: He basically looks like a moving picture of a person on the floor and ceiling.
The Maker: His secondary, if not primary, purpose as Wishmaster is making new universes to grant wishes. This expands the multiverse. However, he cannot make universes if not wished for, and doing so in creating the Fionna and Cake world allows Scarab to detain him.
Nice Guy: Really nice. He seems like an all around great guy.
Never My Fault: Dabbles in this when he blames Simon for messing with his stuff in inadvertently summoning Fionna and Cake, ignoring the fact that he was the one who planted their universe in his head without his consent.
Oh, Crap!:
- When the Lich is about to wake him up instead. It makes a certain amount of sense. The Wishmaster form would simply be incapacitated until his mortal form goes back to sleep in a thousand years, whereas if the Lich kills him, he's kinda screwed.
- He does another one along with the Cosmic Owl when Betty says she's going to rewrite history to prevent the Mushroom War from happening.
Our Genies Are Different: He grants wishes like genies would, but he's two-dimensional, is physically like a shadow and he lives at the center of the multiverse.
Overshadowed by Awesome: One of the most powerful beings on the show, but even he is powerless against GOLB, as he is unable to revive Margles and return Betty to normal.
Reality Warper: He grants wishes that can alter the course of history. However even his powers have limits — he can't bring back those who were killed or assimilated by GOLB. Both Magic Man and Simon went to him to try to get Margles and Betty back. Both times Prismo could only conjure a waste-paper basket-ball hoop.
Screw the Rules, I Have Connections!: Inadvertently. He himself isn't the type to pull strings in his own benefit but other entities vouch for him as a "cool guy" so much that his actual wrongdoings are damn near overlooked. Scarab has plenty of trouble trying to nail him for unauthorized universe creation because his boss Orbo likes Prismo enough to be utterly convinced he'd never do that (and physically threatens Scarab to drop the issue).
Senseless Sacrifice: He allows Finn and Jake to wake up his host body thus destroying his Wishmaster form. He did it so Finn could be sent to the Citadel to meet his real father... who was a manipulative Jerkass extraordinaire and had no interest in Finn at all. Even worse he failed to realize that the Lich would kill him after he woke up meaning without plan B he'd be dead for good as opposed to coming back when his host goes back to sleep.
Stable Time Loop: He's able to avert this without consequence allowing Jake to avert the Lich's wish to destroy all life even when it lead to Jake's wish. Possibly Justified due to being a deity.
Time Master: Sort of. He uses wishes to allow people to navigate The Multiverse and stays in his own time-sealed room, but doesn't really ever leave it. He can view any point in time he wishes and teleport whatever he wants from one point to another. His revival involved the use of a special room with a bizarre flow of time. Beyond creating a temporal duplicate of Jake to serve as Prismo's new 'host', Finn's time double becomes the Finn Sword.
Took a Level in Jerkass: He becomes a bitter, depressed drunk by the time of Fionna & Cake, and he pulls an especially cruel wish on Wyatt for seemingly no reason. He does seem to improve at the end when he has company in the Time Room once more, even if that company is Scarab.

Cosmic Owl

https://static.tvtropes.org/pmwiki/pub/images/220px-owl_trans_2880.png

Voiced by: Jeremy Shada (What is Life), M. Emmet Walsh (all other appearances)

A mysterious and important entity in the land of Ooo, it appears to others in visions. It speaks in a Southern drawl initially and is a friend of Prismo.

Animalistic Abomination: A golden energy owl that appears in others consciousnesses and according to the Why-Wolves capable of devouring entire populations if they prove too numerous.
Cosmic Entity: The exact details of his powers aren't clear, but the people of Ooo regard him as a being of great importance.
A Day in the Limelight: "Hoots".
Big Damn Heroes: Pops up in the final episode disguised as a singing poodle to interrupt PB and Gumbald's dream-battle.
Dream Walker: By entering people's dreams, he ensures that they come true, either literally or metaphorically.
Loser Deity: "Hoots" reveals that the Cosmic Owl isn't quite as fantastic as he's been built up to be: he lives alone in a seedy motel (a cosmic one but still), has only one-player board games for entertainment, and has limits on what dreams he can enter due to his powers (though it's only a warning).
Energy Being: It is an owl that is made out of yellowish cosmic energy.
Nice Job Breaking It, Hero: In "Hoots", he accidentally is present while Princess Bubblegum was dreaming about the Candy Kingdom's destruction, which allowed King of Ooo to take it over.
Oh, Crap!: He does one along with Prismo when Betty says that she's going to rewrite history to prevent the Mushroom War from happening.
Ominous Owl: Subverted; it's less of a malevolent force and is more of a natural force with some hobbies.
Only Friend: Prismo is his.
Physical God: Easily one of the most powerful entities in the series, but it does not directly interfere in the plot.
Reality Warper: To a certain extent. The way his powers work mean that, whatever the person is dreaming, as long as he is present, it will come true in the real world.
Sudden Sequel Heel Syndrome: Downplayed. When Scarab attempts to go after Fionna, Cake and Simon and ignores his alerts in "The Star", the one he reads reveals that the Cosmic Owl is now wanted for "Profiteering".
Verbal Tic: He hoots whenever he says a word with an "oo" sound.
Vocal Dissonance: One of the most ancient and powerful entities of the series, but it has a youthful, Southern drawl.

Abraham Lincoln

https://static.tvtropes.org/pmwiki/pub/images/e3ff371d0d29e2852c642a9cfc38d04e.png

Voiced by: Pendleton Ward

The King of Mars, and possibly the most powerful being in the Adventure Time universe, with the exception of Prismo.

Balancing Death's Books: He accidentally executed Jake thinking he was the Magic Man. He travels to the Eighth Dead World to bring him back, where he meets with Death. When Death refuses the payment of one penny, the King offers his immortality instead, killing him and turning him to stone (an exact replica of the Lincoln Memorial, in fact).
Early-Bird Cameo: Lincoln appeared as early as the 2006 short in a very... weird scene, and never came back until "Son of Mars" in 2012!
Friendless Background: As revealed in "Sons of Mars":
Lincoln: "My judgement was less than the standard by which I judge my peers... of which I have none."
God-Emperor: He's the Martian King. He also appears to be a god.
Heroic Sacrifice: In order to bring Jake back from the dead, he offers Death his own immortality.
Large Ham: He can be ridiculously hammy.
My God, What Have I Done?: Upon Jake's death, who he thought was the Magic Man.
No Indoor Voice: Well, he's never really indoors.
Nonstandard Character Design: Really the only character in the entire series drawn with vaguely realistic features.
The Paragon: Finn refers to him as "the wisest, most honest superbeing of all time".

Grob Gob Glob Grod

https://static.tvtropes.org/pmwiki/pub/images/747f6797bb651c47ef942dcd0e606737.png

Voiced by: Melissa Villasenor (Grob), Tom Kenny (Gob), Tom Gammill (Glob), Miguel Ferrer (Grod)

A four-faced deity from Mars, and Magic Man's older brother.

Baldness Angst: The weird geometric headgear is to hide the fact that Magic Man used his magic to make him bald.
Cain and Abel: The Abel to Magic Man's Cain.
Cosmic Entity: But like the Cosmic Owl, the extent of his power isn't clear.
Flaming Sword: His weapon of choice, which he used to defeat Orgalog.
The Flatwoods Monster: Takes inspirational elements from this cryptid in design.
God Is Dead: As of "Astral Plane." Subverted in "Normal Man" where it's revealed they're not dead, but have become orbiting entities around Earth/Ooo.
Guardian Entity: Was the guardian of Mars and, to a lesser extent, the rest of the solar system.
Heroic Sacrifice: Seemingly dies protecting the people of Mars from an incoming 'catalyst comet', which turns out to be Martin's spaceship
Multiple Head Case: He has four faces, each of which is a distinct being.
Not Quite Dead: "Normal Man" reveals he survived crashing into Martin's spaceship and his four heads orbit Earth.
Offscreen Moment of Awesome: Implied to have protected Mars from a plethora of dangerous cosmic beings, including Orgalorg and GOLB.
Physical God: A literal god/cosmic being who physically fights to protect the worlds, and capable of striking down an Eldritch Abomination.
Pieces of God: His helmet fell down in You Forgot Your Floaties. Magic Man tried to use it and Betty's true human blood to take his power, but Betty took it instead. And Magic Man's. Also, his 4 heads now orbit the Earth. He's still alive and sentient, but has chosen not to intervene anymore.
Starfish Aliens: Even by Adventure Time standards, he's one of the strangest-looking beings in the show.
The Worf Effect: He's strong enough to defeat the planet destroying Orgalorg with ease, yet is easily blown apart by Martin's Spaceship.

Death

Voiced by: Miguel Ferrer

Ruler of the Land of the Dead, Death has power over the deceased and is able to raise them whenever he wills it. Best friends with Peppermint Butler.

Affably Evil: Despite being an overall nice guy, "The Gift That Reaps Giving" hints that Death will not back down from doing despicable things if it gets him what he wants. In that short, he wants to gift a mixtape to his girlfriend, and decides that the easiest way to acquire one is by murdering an innocent child who has it.
Cooldown Hug: He appears to try one of these on his son, New Death, when the latter begins arguing with Death's attempts to bond with him over gardening. It would've worked if it wasn't for the Lich's machinations.
Deal with the Devil: In "Sons of Mars", Death agrees to resurrect Jake in exchange for Abraham Lincoln's immortality. It's also implied that he once revived someone for Lincoln in exchange for a penny.
The Death of Death: New Death, his son, murders him while under the Lich's influence.
Dem Bones: He appears as an anthropomorphic skeletal equine.
Don't Fear the Reaper: When we actually see him doing his job as opposed to dealing with people invading his territory and trying to resurrect people, Death is rather friendly. He prepares a special trip for Simon with music and everything and both he and his target consider it a Mercy Kill. When said target decides to let the attempt to save him go on anyways, Death steps back to see what happens.
Everyone Has Standards: In spite of the fact that death will reap anyone regardless of age, gender, race,etc. and had no problems doing so even he finds The Lich to be disturbing. While the extent of their relationship or interaction, if any, is unclear, it had been stated per Word of God that the Lich has never beaten death and only cheated him.
Horrifying the Horror: Even Death is freaked out by the Lich hanging out in Prismo's dimension.
Intangibility: Apparently you can't kick him if your brain is stupid (or he was commenting on the idiocy of trying). More seriously, the creators state that even the Lich hasn't beaten him, merely cheated him. Though the Lich finally got to beat him in a way by using his own son to "kill" Death and take over as New Death.
Kiss of Death: Subverted. A kiss from Death gives you your memory back.
Light 'em Up: Lives in a castle of light. This doesn't affect his morality much.
Nice Guy: When not angered, he's a pretty nice guy surprisingly. This is particularly true with his girlfriend, Life, who he tries his best to get a birthday present for.
Rock Me, Asmodeus!: For a skeleton, he's quite skilled with a guitar.
Serious Business: Musical battles.
Death: Those the rules of the Land of the Dead; lose a music battle, lose your life.
Stealth Pun: He plays Death Metal in a musical battle.

Life

Voiced by: Hynden Walch, Corrine Kempa ("Together Again")

The personification of life. Death's girlfriend. Appears in the digital shorts "The Gift That Reaps Giving" and "Frog Seasons: Winter".

Abusive Parents: She admits she has no love for her family, and that all she cares for is her job. This despite having a son.
Berserk Button: Attempting to impede her job will enrage her in such away that she'll do everything to help kill the one responsible, even if that person is her own son.
Bewitched Amphibians: An odd example - the "Frog Seasons: Winter" short has the frog Finn and Jake have been following turn into Life after putting on its crown.
Bilingual Bonus: After finding out in Together Again that New Death has stopped the cycle of reincarnation, she furiously mutters in French as she assembles the Kiss of Life, the artifact meant to stop him. Doubles as a bit of Genius Bonus, as she was in a loving relationship with Death...and French is often called "the language of love".
Life: HE DID WHAT?! He's willing to snatch my entire purpose from ME?! Après tout ce que j'ai fais pour ce garçon, après tout ce que j'ai fais pour lui. Non mais c'est pas possible, ce n'est pas possible. Non ça me... ça m'infurie complètement! Mais c'est pas possible!
(Translation:"After all I did for that boy! After everything I did for him! No, but it's not possible! That's not possible! No, I'm... I'm completely infuriated! But that's not possible!")
The Cobbler's Children Have No Shoes: It should be noted that she's a creator of life. That is, she's not very good at or interested in raising anything she makes, including her son.
Fertile Feet: Plants grow wherever she walks. When she kisses Death's cheek flowers grow, which naturally wilt instantly.
It's All About Me: She only agrees to help stop New Death after she finds out that his demolishing of the Dead Worlds will get in the way of her purpose. Downplayed by her Bilingual Bonus rant revealing she did many things for her son before.
Married to the Job: She states as much herself, saying she cares for her job as opposed to her family. She refers to the process of reincarnation as her entire purpose and it being cut off drives her to create a weapon for Finn and Jake that can kill New Death.
Multiple Headcase: She has two intertwined snake heads, likely a reference to the Greek caduceus as well as the Aztec life goddess Coatlicue. She grows thirteen extra heads (and four extra arms) when angered.
Offing the Offspring: Though she doesn't do the deed herself she creates the Kiss of Life to kill her own son in retribution for what he did to his father and his attempt to stop reincarnations.
Opposites Attract: The personification of life is in a long-time relationship with the embodiment of death. Also, Death cares for his son quite deeply, although this doesn't stop New Death from killing his father, and goes out of his way to get Life a gift for her birthday, while Life herself states she doesn't care for her family.
Reincarnation: She's in charge of it; in her realm she molds new bodies out of clay for recently arrived souls to be reborn in. Sometimes she does pairs for souls that are a "package deal". When she hears that reincarnation is going to be ended by her son New Death becomes utterly enraged enough to give Finn and Jake the means to kill him.
Snake People: As mentioned above her head is composed of two snakes, making her an odd version of this trope.
Voice of the Legion: Her heads speak simultaneously creating this effect.

New Death

See Antagonists and Enemies

Catalyst Comet

https://static.tvtropes.org/pmwiki/pub/images/purple_comet.png

Voiced by: Tig Notaro

The otherworldly force that causes major and often dangerous changes in the world whenever it passes. In "The Comet" it is revealed to be sentient and actually rather benevolent.

Alien Geometry: It's really a hollowed-out sphere with 3 eyes.
Arc Villain: Sorta one for season 6. Subverted when it's revealed to not really be evil.
Ascended to a Higher Plane of Existence: Its offer to Finn, which he declines. Martin is eager to take it up, though.
Comet of Doom: Causes catastrophic events whenever it passes. It turns out that it isn't a malevolent force, but rather just an agent of change.
Did We Just Have Tea with Cthulhu?: An eternally recurring comet that strikes Earth every 1,000 years, but when Finn meets it, it casually engages in conversation with him, and even offers him a choice for a new mode of existence with it, which it's fine with when Finn declines.
Long List: Tells Finn about the attributes and events in his life while bringing up its cosmic offer, and when Finn points out that it's just droning on, the comet defensively states that it's a long list.
Purple Is Powerful: It can alter the course of reality itself!
Walking Spoiler: Due to its sentience and intentions.

Wishy

Voiced by: Thurop Van Orman

A magical entity living in a crayon-like dimension who grants wishes to those who seek him out.

Equivalent Exchange: His wish-granting costs a piece of the wisher's soul. He doesn't mention this, so it's not exactly a Deal with the Devil.
Sugar Bowl: We don't see much of his dimension, but given that what we do see consists largely of clouds and rainbows and looks as though it was drawn by a child, it can be said to fit this. The only thing casting doubt on this is that the Ice King requires a demonic wishing eye to get there.
Voice of the Legion: In contrast to his cutesy design and the Sugar Bowl aesthetic of the world he resides in he speaks in a voice that very much fits this trope.

Kheirosiphon

Voiced by: Andy Daly

A cosmic entity formerly tasked with guarding sacred flames only to abandon his post to become a teahouse owner and is later hunted down by Scarab for it.

Dangerous Deserter: Is classified as being this in Scarab's criminal database despite just wanting to live out his days serving tea to customers.
Earn Your Happy Ending: In the epilogue of Fionna and Cake he finds work as a waiter at the bakery in Fionna's world after escaping imprisonment and the battle with Scarab is over.
Elemental Personalities: A fiery being with an equally fiery personality once he drops his mortal disguise.

Scarab

See Antagonists and Enemies

Orbo

Voiced by: David McCormack

A high-ranked cosmic entity and Scarab's superior.

Beware the Nice Ones: He's rather affable but even Scarab knows better than to tick him off.
The Dragon: Seems to be this for the Top God.
Pointy-Haired Boss: He completely ignores Scarab's report that Prismo has created an unauthorized universe because he thinks Prismo is cool. He even physically threatens Scarab for refusing to drop the matter.
Reasonable Authority Figure: He summons Scarab before he can finish tracking down Fionna, Cake and Simon. While the audience knows Scarab is right about what Prismo has done Orbo is in the right to judge Scarab putting off his own duties for a seemingly baseless vendetta against Prismo.

"The Boss"

https://static.tvtropes.org/pmwiki/pub/images/bossphone.png

The Boss' phone

The highest-ranking entity in the cosmic chain of command.

The Dreaded: Is so powerful no other high-level being wants to draw their ire lest they receive horrible punishments for it.
The Ghost: They've been mentioned multiple times but have yet to make an onscreen appearance.
No Name Given: They're only ever referred to as "the Boss" with their real name being unknown.
No One Sees the Boss: They only communicate with subordinates via a golden handset with an angel and devil wing that descends from offscreen.
Reasonable Authority Figure: They're willing to extend Scarab one last chance to apprehend Fionna and Cake when he claims he's just trying to do his job. When it becomes clear Scarab was actually acting out a personal grudge they strip him of his god auditor position and demote him to being Prismo's assistant which is notably more mild than the punishment Orbo had in mind.
Top God: Is deemed this out of all known celestial beings.

Inhabitants of Outer Space

The Drift

https://static.tvtropes.org/pmwiki/pub/images/y5_transparent.png

Voiced by: Glory Curda

A young teen scientist who lives on The Drift.

Beware the Nice Ones: She finally snaps near the end.
Calling the Old Man Out After spending so long pining for her parents' approval, she eventually calls them out for never listening to her before going off to save BMO and expose Hugo's schemes.
Character Development: She starts out as someone who simply does as she's told and afraid to speak her mind, but her bonding with BMO helped her grow into a more heroic and confident person.
Deuteragonist: Of "BMO".
Does This Remind You of Anything?: Y5's distaste of her given name, Y4, and initially hiding her preferred name from her parents out of fear they wouldn't accept her is very reminiscent of the struggles of a closeted trans kid or teen, with one of the writers even welcoming that interpretation of her character.
Good Feels Good: How she feels after helping BMO save the thieving bug duo.
Heroic BSoD: She goes through a brief one after she realizes that Hugo's behind The Drift's gradual decline.
The Lancer: She acts as the more practical, grounded foil to BMO.
Nice Girl: Y5 is a good natured rabbit.
Righteous Rabbit: Y5's a rabbit-like humanoid and one of the main heroes of "BMO".
Tricked-Out Shoes: She sports a pair of gravity-altering boots that allow her to walk on walls and even hang upside down.

Olive

A silent shapeshifting service droid that acts as BMO's sidekick when he ends up on The Drift.

Meaningful Name: Olive is green, has an antenna and has a red pupil, loosely resembling a pitted, pimento olive with a toothpick.
The Speechless: It never speaks, and presumably can't due to lacking a mouth.

CGO

https://static.tvtropes.org/pmwiki/pub/images/cgo_render_without_wires.png

Voiced by: Simone Giertz

A small robot that works in The Drift's garbage pod.

Mr. Exposition: She's the one to tell Y5 about Hugo's backstory.
Poor Communication Kills: She knew all along about Hugo's true nature, but nobody bothered to talk to her (or if they did, didn't believe her) because she was just a lowly garbage-sorting robot.
Shoddy Knockoff Product: She admits that she's basically a bootleg MO.

Others

Space Moth

https://static.tvtropes.org/pmwiki/pub/images/s6e41_martin_on_moth.png

A gigantic... well, moth that provided milk for the koala people before Martin hijacked it.

Ascended to a Higher Plane of Existence: Alongside Martin in "The Comet".
Big Creepy-Crawlies: It can easily fit Martin and Finn in its mouth.
Non-Mammal Mammaries: Somehow, despite being a moth, it provides milk.

Martin 2

The leader of the koala people that Martin takes a liking to.

Morality Pet: Averted. While Martin seems fond of him, even giving him a nickname, he leaves Martin 2 high and dry when it turns out he was the one the guards were after the whole time.
Older Than They Look: He turns out to be an old man, which we don't find out until a Gross-Up Close-Up of him.
Pintsize Powerhouse: He is able to hold his own against several guards many times his size.

Characters / Adventure Time: Other Characters