"Adventure Time" is a mind-bending cartoon that's full of colorful, post-apocalyptic worlds. Finn, the human, and Jake, the dog, travel these worlds, rescuing princesses and other creatures. Sometimes they're on a quest to save the whole world, other times they're just looking for a good sandwich. Finn's bravery and Jake's shape-shifting power get them in and out of all kinds of scraps.

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The friendship between Finn and Jake is at the heart of "Adventure Time." Finn may be Jake's adopted brother, but even without familial ties, they would never turn their back on each other. No matter what challenges they face, or what their love lives are doing to them, Finn and Jake rely on each other, through good times and bad.

On that note, here are 15 episodes when Finn and Jake have proven their friendship is more important than anything else.

WARNING: The following list contains several "Adventure Time" spoilers!

15 TROUBLE IN LUMPY SPACE

"Trouble in Lumpy Space" is the first time Finn and Jake go on a real quest. Lumpy Princess accidentally bites Jake, which infects him with her lumpiness. She leads them through a portal to her world where they can get the cure to lumpiness. Although they're worried, Finn is determined to keep Jake from turning lumpy. He takes over the mission, saying he'll save Jake even if he has to "sock the lumpiness" out of him.

In Melissa's car, on the way to the cure, Jake starts to tell Finn what to do if he turns lumpy. Finn interrupts him to say he's even willing to kill Jake to save him. Shocked, Jake explains he just wanted Finn to get used to him as a lumpy person, not kill him. Even when Jake's body succumbs to lumpiness, and Jake rejects Finn with all kinds of attitude, Finn keeps trying. He tricks the surrounding lumpy residents to bite him, knowing that Jake will snap out of it when he sees his best friend get infected. Finally, the cure works on both Finn and Jake, and they celebrate at the weekly Promcoming.

14 HER PARENTS

Finn goes above and beyond to help his best friend in "Her Parents." Jake is worried about meeting Lady Rainicorn's parents for the first time, especially because he thinks they hate dogs. Using copious amounts of condiments, Finn helps Jake disguise himself to be a Rainicorn. Lady Rainicorn's parents arrive and are completely fooled by Jake's disguise. However, they think Finn is Jake's human servant. Because he's a good friend, Finn endures all manner of abuse at their hands. Every time he begs Jake to call off the ruse, Jake pleads with him to keep going. As they say, "Homies help homies."

The tipping point comes when Lady Rainicorn's parents want to eat Finn. Jake finally confesses that Finn isn't his servant, but his best friend. By this time, poor Finn is bruised and beaten, but he was willing to endure all that pain to help out his best friend. Jake's love for Finn is what saves him. Not even winning the approval of Lady Rainicorn's parents can keep Jake from sticking with his buddy.

13 STORYTELLING

When Jake falls ill in "Storytelling," he begs Finn to tell him a story that's original and that isn't fictional. Finn sets out to find adventure, so he can return to Jake with an original and real story. Unfortunately, the forest and its inhabitants don't cooperate. Every time Finn is met with an obstacle, however, he reminds himself that he's there for Jake. He cringes when he offends other characters. He eats dirt in exchange for watching a fox and a goose kiss, which winds up sending both of them running away in tears. Over and over he screws up, but he keeps searching for a story, because he's Jake's best friend.

Finally, Finn is captured and he's in danger of being killed by the forest animals. He realizes that he now has the perfect story to tell Jake, one that's full of suspense, if he can just stay alive. After talking his way out of the forest, he tells Jake the story, which completely cures Jake. Good friend that he is, Finn saves Jake, only to come down with the same illness.

12 CRYSTALS HAVE POWER

It's Jake's turn to show Finn how much he cares by sacrificing his morals to save his friend in "Crystals Have Power." While they're roughhousing, Jake accidentally hurts Finn and swears he'll never hurt anyone ever again. Unfortunately, Jake makes that promise just before they get sucked into a hostile crystal world. The crystal guards imprison Finn, then begin torturing him and turning him into crystal. Finn begs Jake to save him, but Jake desperately wants to stay true to his recent oath, even though he loves his friend.

Jake tries to save Finn without actually resorting to violence. First, he tries talking to the guards. Then, he grows in size but only taps the guards, which ends up annoying them. Jake is still "figuring out his biz" when Finn completely turns into crystal and they find out Tree Trunks has turned evil. Then, Jake has a vision of his father, who tells him it's okay to use violence against evil people. Jake finally puts aside his doubts and, with Finn's encouragement, kicks the crystal out of Tree Trunks. Jake saves his best friend using his shape-shifting ability. Like a good friend, he apologizes for not saving Finn sooner.

11 TO CUT A WOMAN'S HAIR

Once again, Finn has to rescue his buddy by giving up something of himself in "To Cut a Woman's Hair." Jake gets pinned under the evil Tree Witch's butt when she demands that Finn retrieve some princess hair to cover her bald head. While Finn deliberates about how to save his friend, Jake gets sucked, inch by inch, into the witch's "bottomless bottom." Desperate, Finn runs from princess to princess to find some hair to give to the witch. He's willing to get punched by Muscle Princess and chased by Lumpy Space Princess. He finally manages to get some of Princess Bubblegum's hair, which turns to be just bubblegum.

Finn tells the Tree Witch he's no good at talking to women. Just as the Tree Witch is about to disappear Jake for good, Finn gathers his courage and tells the Tree Witch that she's so ugly, no amount of princess hair is going to make her look more attractive. When she explains she just wants to love herself, Finn decides to give her his own long, luxurious, golden locks. He cuts off all of his own hair to save Jake.

10 INCENDIUM

In "Incendium," Jake literally walks through fire to help Fiinn. He hates watching his best friend suffer after being rejected by Princess Bubblegum, so he sets out to find him a new girlfriend. A lot of friends might have ignored Finn's pain, or even made fun of him, but Jake shows compassion by looking for someone to replace Princess Bubblegum. Jake hears about a princess in the Fire Kindgom. Lucky for Jake, Flambo makes him fire proof before they enter the King's volcano. Bravely, Jake attempts to curry favor with the king, who wants nothing more than to turn Jake to ash. Instead of turning and running, Jake tries to think of a way to convince the king to let his daughter date Finn.

Everything falls apart, however, when the princess is described as "evil" and Jake tries to back out. Flame Princess chases Jake all the way back to their tree house. Before she can burn the place down, she's doused by rain and Finn sees her for the first time. Jake has mixed feelings about finding a new "baby for his buddy" when Finn tells him he has a crush on Flame Princess, even though she left a scar on his face.

9 CARD WARS

Best friends do stuff for each other sometimes, whether they enjoy it or not. In "Card Wars," Finn not only plays a game everyone but Jake hates, but also takes a dive to keep his friend happy. Card Wars is Jake's favorite game, but no one will play it with him, not even BMO, because Jake gets so nasty when he plays. Finn, however, agrees to a game, even though the loser has to drink a disgusting "Cool Guy" drink. Jake tells Finn the basics of the game, but even as they start to play, Jake's jerk nature starts to show.

Finn, it turns out, is really good at Card Wars, even finding ways of dealing out damage that Jake doesn't see coming. Finn's success makes Jake angrier and angrier, until BMO warns Finn that no one wants to see what happens when Jake loses. Always a good friend, Finn knows that winning isn't as important as helping his buddy save face. Finn purposely ruins his own game and winds up drinking the "Cool Guy" drink.

8 THE PIT

Finn faces a different kind of trial when he has to save Jake from Kee-Oth the Blood Demon in "The Pit." Kee-Oth mistakes Jake for his father, Joshua, and throws him into a stone pit, where Kee-Oth extracts Jake's blood. Back at the tree house, Finn calls on Lady Rainicorn and BMO to help him figure out a way to save Jake. They discover a videotape that may hold the answer to defeating Kee-Oth. However, Finn is forced to watch Jake's sexy videos for Lady Rainicorn. Even with the possibility of seeing his best friend put on a show for his lady love, Finn endures the rest of the tape to discover Jake's dad had a special sword made out of the demon's blood.

Finn joins forces with Lady Rainicorn to save Jake. Their friendship is so strong that Jake tells Samantha, the dog goddess, that Finn will be there any minute to save them. Finn and Lady Rainicorn arrive in the broke-up dimension where Kee-Oth is holding Jake. Finn's clever thinking and bravado, however, are enough to defeat Kee-Oth. He pulls a trick worthy of their friendship.

7 IS THAT YOU

"Is That You" is difficult to write about because it's a trippy episode involving a "Groundhog Day" kind of scenario, if "Groundhog Day" were layered on top of itself. However, the gist of the episode is that Prismo is brought back to life by Jake eating one of his delicious pickles. But by doing so, Jake puts himself on some kind of mind-blowing time loop. First, Finn has to figure out why Jake keeps blowing up. Then, without even thinking twice, Finn follows Jake into Prismo's pickle jar to save him.

While Jake is caught in a dream, Finn has to follow Prismo's crazy instructions to save Jake and keep Prismo alive. He tears Jake from nothing less than Nirvana to save him. Even though Finn might explode, he goes for it, saying, "Heroes risk everything for their friends." Finn is rewarded with more than just having his best friend back; he gets a Finn Sword in the bargain.

6 HALL OF EGRESS

"Hall of Egress" is the kind of episode that hurts your brain. It's also about the strength of friendship. Finn gets trapped in a cave that has mystical and mystifying rules that he can't figure out. Time and again, he attempts to leave. Each time that it seems like he's escaped, he opens his eyes and the illusion disappears. He even goes a whole month, at the tree house with BMO and Jake, keeping his eyes closed. Unfortunately, Jake feels sorry for him, and doesn't believe him, so he yanks his eyes open and Finn winds up back in the cave.

You may be saying, that's not a good friend, right? But Jake only wanted to help Finn. It's not until Finn takes off on his own, eyes closed, and walks full circle around Ooo back to the entrance of the cave that he's able to take off his three blindfolds and open his eyes. The joy he has when he spies Jake outside is magnificent. The two of them celebrate Finn's return by swinging each other in circles, merry-go-round style. The friends should have never separated to begin with.

5 MEMORIES OF BOOM BOOM MOUNTAIN

In "Memories of Boom Boom Mountain," Jake helps Finn follow through on a crazy plan, even when he disagrees with it. Finn is determined to help a crying mountain because of his own childhood traumas. What begins as a mission to help the mountain grows into a mission to help everyone, even though what they want is at odds with each other. The mountain wants everyone to stop roughhousing, but the men doing the roughhousing love it and don't want to quit. Finn works harder and harder to make everyone happy while driving himself crazy.

During all of Finn's nutty attempts to make everyone happy, Jake remains loyal to him, even while trying to talk him out of what he's trying to do. He thinks Finn is crazy, but helps him on his mission anyway. Jake goes as far as to thank the roughhousing, viking-looking men for going along with Finn's wacko plan.

4 THE WITCH'S GARDEN

Finn and Jake stumble into a witch's garden. She accuses Jake of eating her donuts. He begins to argue, but realizes he really is eating all of her donuts. She strips him of his powers and gives him a man's body, but Jake refuses to apologize to get his powers back. Finn sticks by Jake's side, even though Jake really was eating her donuts. "Total support, dude." Finn says, vowing to help Jake get his powers back.

The journey is exhausting for Jake, but because Finn wants to help his friend, his energy is boundless. They wallow in mud puddle after mud puddle, trying to restore Jake's powers without having him apologize to the witch. At one point, Finn winds up about to become dinner for a bunch of giant baby birds. Jake finally realizes he needs to swallow his pride and apologize if he intends on getting his powers back to save Finn. Jake allows himself to be completely humiliated for the witch, forced to dance with flowers and act like a fool. Once Finn is safe, Jake tells him "In a crunch, there's nothing I wouldn't do for you."

3 DUNGEON

"Dungeon" sees Finn and Jake start the episode as friendly enemies. Finn claims he can steal treasure from a dungeon without Jake's help, saying "I'm in my element." Jake says Finn will get killed if Jake and his powers aren't there to save him. In response, Finn jumps into the dungeon, fully confident that he doesn't need Jake.

As Finn travels through the dungeon, however, he realizes that Jake would be much better at facing the obstacles and enemies that keep cropping up. Even when Jake isn't there, he technically manages to save Finn, because the demon kitty in the dungeon leaves Finn alone after smelling Jake's stink on him. As it turns out, Jake has been on his own mission. The two of them wind up literally in the soup, together. Jake confesses that the challenges he faced were difficult for him, but Finn would have had no trouble. They realize that they can beat the dungeon together, because they're better as a team.

2 WHO WOULD WIN

"Who Would Win" is another episode that begins with Finn and Jake at odds, but ends with the two of them realizing they're better as partners. Finn wants to take on The Farm, who is a giant creature that's beating the goat cheese out of everyone who challenges him. Finn asks Jake to train with him, but Jake's heart just isn't in it. The two of them end up beating the corn meal out of each other after Finn destroys Jake's Kompy Kastle portable game.

Beaten and bruised, exhausted and weary, Finn and Jake attempt to take on The Farm. However, they fall asleep and find themselves in the same dream. Dream Warrior gives them cryptic advice on how to beat The Farm, which makes Finn and Jake realize that the same cheap moves they used on each other are what they need to defeat their opponent. Working together, they are able to beat The Farm.

1 JAKE THE DOG

"Finn the Human" and "Jake the Dog" is a two-part episode that explores what Finn and Jake would be like in an alternate reality. After Finn wishes that the Lich had never existed, he's thrown into a world where he has big eyes, a real nose and a family. In the alternate reality, however, Finn winds up taking on the Ice King's powers and setting off a bomb that destroys the world. Jake, who is a real dog in this reality, falls into a pit of toxins. Finn is distraught, and tries to save him, but Jake ends up becoming a monster.

Meanwhile, Jake is hanging out in a hot tub with Prismo, watching all this unfold on a big screen. When Jake realizes his other self has turned into the Lich and is about to kill Finn, he uses his one Prismo wish to save him. Of course, Prismo has to walk him through it to avoid a "monkey's paw" situation. But thanks to Jake's wish, which he could have used on anything, he's able to save Finn and the two of them return home to their own reality.

What's your favorite episode of "Adventure Time?" Tell us in the comments below!