Dawn of The Lich: The Adventure Time Movie is the American animated film based on the Cartoon Network animated television series of the same name. It is produced by Cartoon Network Studios and Frederator Studios for Warner Bros. Pictures and Cartoon Network. The film used footage from the episodes Mortal Folly, Mortal Recoil, Too Young, In Your Footsteps, The Lich, Finn The Human, and Jake The Dog.
Chapter 1: Mortal Folly
Finn, Jake, and Princess Bubblegum are meditating on the balcony of the castle. At first the boys have trouble concentrating, but the princess tells them to clear their minds and it works. Finn has a vision of himself older and cooler with new powers such as having a mechanical arm. Jake has a vision of Lady Rainicorn riding a horse. Princess Bubblegum has a vision of a dark figure and panics before saying she needs to check on something and Finn and Jake decide to go with her. She gives Finn and Jake gems like the one in her tiara before entering a secret room in the heart of the tallest tree where she shows them an ancient evil sorcerer called The Lich held in a prison of amber and explains that the gems will keep themselves safe from the Lich's spells that control and possess people.
Then she tells the story of how he plotted to destroy Ooo and kill everyone until The Hero Billy pushed him into the resin of the amber. As she explains, however, the Waving Snail climbs out of Finn's backpack and is quickly possessed by the Lich for not wearing the jewelry. The Snail makes a crack in the amber, and the Lich is quickly freed. When Finn and Jake try to stop him, the Lich escapes and he heads towards the skies. Princess Bubblegum then takes them to the other secret room and gives Finn The Gauntlet of the Hero Billy, a gauntlet that Billy used to defeat the Lich the first time, and tells him to smite the Lich with it before he gets to his Well of Power and gets his magic back. She also tells Finn that the Lich's lair is cold so she gives him a sweater that she made, telling him she cares for him. As one last parting the trio hugs each other for good luck.
While they're hugging, a latched window opens up revealing the Ice King who butts in, asking Finn and Jake to bless his wedding with Princess Bubblegum, which of course they refuse to do. As they journey to find the Lich, the Ice King repeatedly begs for the blessing. After Finn uses the gauntlet on him, the Ice King gives up on the blessing and kidnaps the princess while she is eating ice cream in hopes that Finn and Jake are alright. All the while, Finn and Jake are in pursuit of the Lich, following the destruction he has left behind. As they reach the end of Iceberg Lake, just as Finn prepares to smite the Lich with the gauntlet, the Ice King interrupts them yet again to show them he kidnapped Princess Bubblegum. While he does this, the Lich makes it to his well releasing hundreds of evil souls from the entry, so Finn and Jake hurry down, and the Ice King follows.
Finn manages to fight off the Skeletal Guards that try to block his path, but his pack is ripped to bits while fighting. After blowing a hole in the ground with the gauntlet, Finn manages to grab hold of a hanging pipe leaking toxic waste, which forms the Lich's Well of Power in the chamber below, where The Lich begins his power rejuvenation. Finn tries to smite the undead creature with his gauntlet, but the Lich, having regained some of his old power, grabs hold of Finn's wrist and turns the gauntlet to dust, burning Finn's hand in the process. With their main weapon destroyed, Jake tries to 'bark' the villain, but is struck in the face with fire and knocked out, and when he falls, Finn's protective jewelry breaks and the Lich successfully possesses Finn's body in an instant.
The Lich compels Finn to walk into the Well of burning toxic waste, asking him if he is cold, but Finn resists his influence by screaming, "I HAVE A SWEATER ON!!!." The Lich, having failed to take control of Finn's body completely, decides to destroy him with his flames, but they too fail to kill him. Finn realizes then that the sweater Princess Bubblegum made for him is keeping him safe, for it has the power of love in it, but Finn feels embarrassed saying love so he says "Liking someone a lot."
Finn fully escapes the Lich's possession, and charges at him with his sweater, jumps on him and pulls the sweater through his eye sockets. As the Lich struggles, trying to burn Finn while laughing hysterically, Finn pulls the sweater vigorously upwards until the Lich's face is broken off and his body turns to dust. After Jake makes sure Finn is okay, the Ice King, in celebrating the victory he had no part in, decides to set Princess Bubblegum free, but in doing so, he stupidly drops her into the boiling well, much to Finn and Jake's horror.
Chapter 2: Mortal Recoil
A few minutes later, Dr. Ice Cream and Nurse Poundcake, along with other candy hospital staff, rolling her into the ER trying to stabilize her, luckily Princess Bubblegum is brought back to life after a small flat-line. Ice King tries to explain something strange he saw when Princess Bubblegum fell in the well, but Finn is still extremely mad at the Ice King for almost killing her and nearly kills him by throwing his Root Sword at him, telling him to "shut Ice King's face" and calls him old. This hurts him emotionally, so he flies away. As a gift for destroying the Lich, the other princesses give Finn a new backpack, since his old one got ripped. Princess Bubblegum is still very ill and is confined to her room, with Finn and Jake acting as her caregivers. When she wakes up she is given a gift of every flower in the Candy Kingdom picked for her.
However, she exhibits strange behavioral problems including spasms, heavy breathing, convulsions, and crawling into the bathroom. Finn returns her to her bed and takes some time to confide his feelings to her, asking Jake to leave the room. Finn thanks her for the sweater she made him due to it have "the power of liking someone a lot" because she cared about him and tells her that they should discuss their feelings later, but she is unresponsive. Princess Bubblegum asks Finn in a whisper to bring some objects for her. When Jake and Peppermint Butler return with a cup of tea, Peppermint Butler freaks out, then hisses like a cat and runs away.
While Finn's away, Jake tries to play some music for Princess Bubblegum, but Princess Bubblegum acts psychotic and summons magical fire into the room and scares Jake out. When Finn returns to the hall outside, he is holding an assortment of items, which he reveals are things like gasoline, bleach, ammonia, lighter fluid, plutonium and other hazardous chemicals. Jake urges Finn to not bring the chemicals to Princess Bubblegum, but she opens the door and takes them from Finn and returns to her room.
Jake then tells Finn of the fire she summoned, which alarms Finn. He asked how, which Jake replied "With her brain, I think." The two enter the room where Finn believes Princess Bubblegum is just having private time in the bathroom. When Jake looks through the keyhole, Finn states it is "pervy," but Jake makes him look in. They see Princess Bubblegum, now with a demonic form, pouring the chemicals into her bathtub, forming a pool like the Lich's Well of Power. When she starts drinking the liquid, Finn and Jake try to stop her, but she rips the tub off of the floor and drinks the entire concoction, growing as tall as her tower and turning deadly black.
She knocks the boys through the wall into the hallway, and as she begins to attack the Candy Kingdom, Ice King appears and asks "Hey, are you dead or what?" He then explains that he saw the Lich possess Princess Bubblegum with his "Wizard eyes." He then explains that he had not spoken up because "when you have stanky old wizard eyes, sometimes you see things that are real, and other times it's like crazy, crazy, crazy, in your face all the time." He wants to help Finn and Jake, but Finn angrily refuses his assistance, as it was his fault for stalling them while chasing the Lich and for almost killing Princess Bubblegum in the first place.
After telling Ice King to "get stuffed," Finn tries to defeat the possessed Princess Bubblegum with the sweater she gave him, but fails. As Princess Bubblegum attacks Jake, Finn finally accepts Ice King's help. As Finn distracts Princess Bubblegum, the Ice King freezes her from the feet up. The Candy Kingdom rejoices, but their jubilation turns to shock when Princess Bubblegum falls over and shatters. Dr. Ice Cream, Nurse Poundcake, and Doctor Princess attempt to reassemble her but they don't have enough pieces. Nurse Poundcake then reveals to everyone that Princess Bubblegum is alive, but she is now thirteen years old instead of eighteen.
Now Ice King loses interest in her and flies home. Finn remarks that he is thirteen as well. Princess Bubblegum calls Finn a hero and he and Princess Bubblegum share a loving embrace. As everyone celebrates, the Snail who freed the Lich is seen waving menacingly in the background, with eyes that glow like the Lich's, which shows that the Lich may return.
Chapter 3: Too Young
A few days later, following Mortal Folly and Mortal Recoil, Finn is in the Candy Kingdom on a "date" with 13-year-old Princess Bubblegum. Finn calls Jake, who is at the Tree Fort playing a game on BMO. Jake gives Finn some advice for his date and then hangs up to continue his video game. Princess Bubblegum asks Finn to test an Instant Bath Serum that makes the user sweat cleaning agents. However, it ends up being unbearably spicy. Afterwards, Manfried the Talking Pinata announces the Arrival of the Earl of Lemongrab, who arrives on his Lemon Camel, believes that the Candy Kingdom is in "unacceptable condition," and asserts that he will take control of the Candy Kingdom until the princess turns eighteen again because she is "too young" to rule the kingdom. Though Finn protests, Lemongrab apparently has this right. Being the creation of Princess Bubblegum from a failed experiment, he assumes the right as the next heir to the throne, having been created for the sole purpose of fulfilling royal duties if Princess Bubblegum herself became unable to do so. A high-strung, strict, overzealous, and true to his name and shape, sour individual, he sentences members of the castle staff to the dungeon with little to no provocation. Finn and Princess Bubblegum realize that because Lemongrab is rightful ruler, they must get him to leave the Candy Kingdom of his own accord, and attempt a series of pranks to make him leave.
The first involves making an intricate machine that lowers an insulting sign for the Earl to read upon waking from his nap, which reads, "You really smell like dog buns." The Earl overreacts to this prank immensely, gathering together all of the Castle Staff and screaming at them to reveal the culprit of the "thing". When Peppermint Butler informs Lemongrab that the "thing" was just a prank for laughs, Lemongrab attempts to laugh at it, but fails and sends Peppermint Butler to the dungeon for 12 years, and everyone else for 7 years with no trials. After seeing that the first prank didn't work, Princess Bubblegum becomes disheartened, but Finn reassures her that they just need to keep at it, and devises a new prank. They disguise themselves as ghosts, approach Lemongrab in a hallway, punch him in the gut, and knock him to the ground. Even though Lemongrab cries after this prank, he tries to laugh it off and vows to not leave the Candy Kingdom. With Lemongrab not showing any signs of wanting to leave, they run to one of the castle's roofs where Finn devises another prank: dripping the spicy serum from earlier onto his meal and into whatever he tries to soothe the burning with. The Princess accepts the idea, not without flirting with him by sighing and relaxing on his body, which makes him blush and sigh, too. Having released Peppermint Butler from the dungeon early because of his lack of knowledge of where food comes from, Finn and Princess Bubblegum hide in the ceiling of Lemongrab's room and prepare to drip the potion onto Lemongrab's meal, but Princess Bubblegum's aim is off and accidentally drips the potion into Peppermint Butler's eye, causing him to scream in pain. Princess Bubblegum tries again, this time hitting the food, and upon eating it, Lemongrab turns red, vomits, screams in agony, and falls out the window.
Upon crashing into the ground, he tries to soothe his mouth by eating the chocolate dirt, but Princess Bubblegum drips another drop of potion straight into his mouth, resuming the spiciness. Lemongrab hurries out into the forest and tries to grab an apple to placate his searing mouth, but grabs an apple from the branch that Finn, Princess Bubblegum, and Peppermint Butler are sitting on, causing Peppermint Butler to fall straight into Lemongrab's mouth, effectively cooling it. Upon seeing who is responsible for the spice-bombing prank, he sentences Finn and Princess Bubblegum to "One million years dungeon!" Inside the dungeon, along with the rest of the castle staff, Finn tries to devise a new prank, but Princess Bubblegum realizes the only way to get Lemongrab out of the kingdom is to become eighteen again and take back the throne, despite enjoying being a kid again. Finn appears to be saddened by her decision, but understands that there is no other way to save the Candy Kingdom. Princess Bubblegum then conveys that she needs candy flesh to increase her biomass back to that of an 18-year old. The Candy People graciously pitch in and offer parts of themselves for her use. Finn provides the "binding agent" with his saliva.
Finishing the process, Finn and Princess Bubblegum are ready to catalyze the pieces with the heat of a "whopping love-hug." Just before they do, Princess Bubblegum tells Finn she really enjoyed hanging out with him, and regrets having to re-age by saying: "And I... I wish I could stay, like this, with you, but...." As they hug, they share their first kiss. Now eighteen again, Princess Bubblegum kicks Lemongrab out of the kingdom and reclaims her throne with the words "Yo, Earl! Hey, you're fired, ya' butt!" In the end, Finn and Princess Bubblegum watch Lemongrab leave the Candy Kingdom on his Lemon Horse, mumbling angrily to himself. Finn nervously asks Princess Bubblegum for another hug, but she jokingly reminds him that that was "five years ago." Finn is greatly disappointed, and calls Jake, who comforts him with advice conceived from his exploits from the videogame he was playing, as he says, "It's not easy, but you have to be persistent. You might have to defeat a demon lord, or warp through several worlds. But once you do, you walk up the wizard stairs, and produce your magic key you got in the water world and unlock the chamber door. Then, you walk right up to the princess, and give her a smooch... Does that make sense?"
In afterwards, Finn looks up to see a distant Princess Bubblegum in a high tower in the castle as he thinks of walking up to her, repeating the part of Jake's words about the wizard stairs.
Chapter 4: In Your Footsteps
A few weeks later, after Princess Bubblegum turns eighteen again, Finn is skydiving in the air with Jake in his backpack. Finn pulls the ripcord and Jake then shape shifts into a parachute. Finn and Jake land safely on the ground. Finn greets Princess Bubblegum and the Candy People once they safely reach the ground. After Finn and Jake were dancing, Finn said that he would go get some food.
Jake meets a Bear and tries to introduce himself to him, who doesn’t understand Jake. The Bear then tries to eat some of Finn’s peanuts, but starts choking. Finn hits the Bear’s back with the Enchiridion and the Bear spits out the peanuts he was choking on. Everybody then continues dancing. After the party, when Finn and Jake are walking home in the dark, the Bear follows them. They go back to the Tree Fort.
Jake is listening to music when Finn shows that the Bear copies everything Finn does. When Jake tries to get the Bear to copy him, the Bear pushes Jake away. The Bear then repeats Finn by saying “Sweeping weak.” Finn suggests that the Bear spend the night in the Tree Fort in the bathtub.
Jake wakes up in the middle of the night when he hears a noise. He sees the Bear dressed up as Finn and dancing. The Bear continues to repeat “Hey Princess Bubblegum! Hey everybody!” while snapping, just like Finn did in the beginning of the episode. When Jake tries to prove to Finn that the Bear was impersonating him, the Bear is sleeping. Finn says that he believes Jake but that the Bear isn’t hurting anybody, so it is fine. During the next morning, Finn, Jake, and the Bear are eating cereal at the table. Finn then says that he has to go pick up BMO from soccer and tells Jake not to eat the Finn cakes. The Bear ended up eating all the Finn Cakes and Jake records the whole thing. When Finn and BMO come back, Finn first gets angry at Jake for eating the Finn cakes, but after Jake explains that the Bear ate them, Finn gets angry at Jake for just letting it happen. They both discover a note that says that there would be a party in the forest at night, supposedly hosted by Finn.
Finn and Jake then go into the forest and see the Bear, disguised as Finn, partying with Princess Bubblegum and the Candy People. Finn tells Jake that he and Princess Bubblegum never went steady when Jake tells Finn that the Bear is stealing his ex-girlfriend. Jake then convinces Finn that the Bear never really liked Finn, and that the Bear just used him. Finn rips the Bear’s mask off and tells him that the jig is up. The Bear runs away, crying. After Princess Bubblegum explains that nobody actually thought the Bear was Finn, Finn runs after the Bear and apologizes. He gives the Bear the Enchiridion and tells him that he can become a true hero. The Bear climbs up a mountain and goes into a cave. The Snail emerges from the shadows and asks if the Bear brought the book. The Bear presents it to the Snail, who is still possessed by The Lich.
Chapter 5: The Lich
Later that night, Finn is having a dream about the Cosmic Owl screeching while Billy and his lady are kissing each other and the bear and the snail are reading the Enchiridion. At one point, while he is laughing, Billy's image flickers to the Lich and back again. Suddenly, the snail turns into The Lich and attacks Billy. Then Finn wakes up. He tells Jake about his dream and Jake says it is a premonition dream. He then says they should go tell Billy because he was in the dream, turns into a car, and then drives Finn to Billy's home.
Once there, Billy yells at them saying that it's three in the morning and asks why they are there. Jake says that they wanted to make sure he wasn't dead, to which Billy asks why they would think that, and Finn proceeds by explaining about the dream. Then a surprising look appears on, Billy's face after Finn is done explaining his interesting dream. Billy asks them if they want to save all life from the Lich and they agree. After they head out, Billy tells them that they need to collect all the magical gems from all the princesses and Ice King's power crystals that protect them from the Lich.
After some time spent collecting crystals, the group stops to rest for a bit and Jake asks Billy how many more crystals they need. Billy indicates that there is one left. Finn gets hungry and rummages through Billy's knapsack looking for candy, finding the Enchiridion after being smacked out by Billy and asking why he had it. Billy says that he found it in the mouth of a bear and Finn blushes with embarrassment as he remembers giving the book away to the bear. Billy says it has magical powers and tells him to turn the sword on the cover of the book which Finn does. The circle on the front opens up showing nine slots where all the gems go in mystically and shows a brief diagram about what would happen if all the slots where filled. At first, Jake and Finn wonder what all the holograms are, but Billy uses the blue crystal on his face to activate another hologram. A man named Booko appears and explains what the first set of holograms represent, which is all the known universes and dimensions, and how they are connected. Jake tries to play around with it, but it frightens him and he calls it off. Booko goes on to mention that in the center of the universe is the Time Room where Prismo dwells. Billy states that he's going to push the Lich into there, seemingly to place the Lich in non-existence. While Fin and Jake are agreeing with Billy’s idea, Billy has another interesting look on his face.
They then go to the Candy Kingdom to get Princess Bubblegum's crystal and Finn breaks through the roof, failing at trying to do so quietly, and after regaining himself, asks for the crystal on her crown. Princess Bubblegum is shocked and refuses, forcing Finn to grab it without explaining why, during which, Princess Bubblegum accidentally cuts Finn's cheek with the scissors she is still holding from her experiments. They stare at each other for a brief moment, both stunned, and Princess Bubblegum says "That was an accident." Finn removes the gem from her crown, drops the crown and is grasped by Jake who stretches out of the room from the hole Finn made when he fell in. Finn and Jake run off with the gem with Princess Bubblegum not far behind who has taken the stairs. Once outside, he then puts the gem in the final slot. Lights start to flash out of the stones on book. Then the book starts to shake while the pieces start to fall off as the Enchiridion turns black after the pieces of the cover slide off and / or illuminate. As Finn is running, Billy tells Finn to hurry with the Enchiridion. Then, Princess Bubblegum runs out telling him that Billy is really the Lich.
Just as she says this, one of the Gumball Guardians gets up and blasts Billy, detecting the Lich's presence, thus revealing half of Billy's face, and showing the Lich's true face. The Lich then asks for the book. Finn realizes that the Lich "messed Billy up" and after dodging a grasp from him, smashes the book with his knee. Then Finn is knocked out by the power of the Enchiridion. Finn, not knowing what had happened, woke up seeing that his action accidentally opens up a wormhole. The Lich laughs because he is pleased and thanks Finn, tauntingly. As the Lich tries to pass through, Jake grabs him, reacting to Princess Bubblegum's request, and stretches as to not go through. Jake, though, is slowly being dragged into the portal as the ground under him gives way. Finn tries to stop Jake from getting pulled in but instead is pulled in with him. After being pulled into portal, Finn and Jake follow the Lich into Prismo's time room. They arrive just in time to see the Lich vanish after making his wish which was the extinction of all life. After a short conversation with Prismo, Finn wishes that the Lich had never existed and is promptly transported into the reality created by his wish.
Chapter 6: Finn The Human
Farmworld Finn is playing his flute with Farmworld Jake, who appears to be a regular, non-talking dog, sitting outside a small house with a barn next to it. His mother calls him in for what she says is "something important," and Farmworld Finn assumes that he has done something wrong and he and Farmworld Jake quickly run inside.
After being called in by his mother, Farmworld Finn is told to go into town and sell their mule Bartram. Farmworld Finn protests, but his mother insists. He follows her gaze out the window to see his father being pushed around by members of the "Destiny Gang." He is seen next talking to Bartram trying to comfort himself, when he notices he is missing. He wanders a little ways to find Bartram in a tree. While going to get him down, he falls into a hole covered by underbrush and Farmworld Jake follows him. Farmworld Finn looks up to see the skeleton of Simon Petrikov with the crown under a frozen bomb. When he sees the Ice King's Crown, he thinks to sell it instead of Bartram and goes to retrieve it. As he nears it, the decrepit Farmworld Marceline jumps out from behind the bomb with a gun. She tells him to back off and that he cannot have the crown. She then tells him of how Simon died 1,000 years ago when the Great Mushroom Bomb was deployed. He used his ice magic to freeze the bomb, but was crushed in the process. The crown, stricken with grief over the death of its master, then unleashed its power and froze the entire earth for 400 years. For 600 years, Farmworld Marceline has been guarding the crown to ensure it never harmed anyone again.
After she finishes her story, Farmworld Finn merely tells her that "None of that is true." and that "Magic is fake." He tells her that she's lost it while living in the cave and proceeds towards the crown. Farmworld Marceline then fires the gun, but finds it is broken and doesn't harm Farmworld Finn. Farmworld Jake then distracts Farmworld Marceline while Farmworld Finn grabs the crown. After Farmworld Finn is gone, Farmworld Marceline has an argument with Simon and she goes after the crown.
Now in the market, Farmworld Finn is trying to sell the crown. A man says he'd take it, but he has no money and offers to sing at his house instead. Tromo, one of the destiny gang, takes the crown and gives it to Big Destiny, under the pretext that "property of old dead person go to Big Destiny" and refuses to give money to Farmworld Finn. Farmworld Finn realizes that the crown wasn't really his and moves on. Farmworld Marceline, however; yells that the crown is her's and that she's half-demon. Destiny then tells Tromo to jack up Farmworld Marceline and Trami to take Bartram for dinner. Trami takes Bartram and runs up to their mansion with Destiny.
As Tromo is attacking Farmworld Marceline, Farmworld Finn shoves his flute into Tromo's nose and then Choose Bruce throws lettuce at him. Tromo then utters that Farmworld Finn has made a big mistake as he retreats into the mansion. Farmworld Finn promises Farmworld Marceline that he will return the crown to her. Choose Bruce then gives Farmworld Finn a sword for his mechanical arm to which Finn replies approvingly stating that it felt natural.
He then runs up to the mansion and down the hall to Bartram, but is tripped by Destiny. Farmworld Finn gets up and begins to sword fight with Destiny, but is hit to the ground. Farmworld Finn demands for his stuff back and Destiny gives it to him as his "last possesion." He then shows Farmworld Finn that he had his henchmen burn the market. Farmworld Finn grabs Bartrum and the crown and runs into the market place. Choose Bruce is weeping and tells him to go save his family. On his way, he grabs Farmworld Marceline and puts her up on Bartram. When he arrives at his house, it has already been set on fire and Destiny is there. Farmworld Finn asks Farmworld Marceline if the crown is magic and she tells him it is very dangerous magic. He then puts the crown on his head, and the power begins to flow through him.
Chapter 7: Jake The Dog
Farmworld Finn puts on the crown and becomes corrupted by its power, going mad. He attacks the Destiny Gang and puts out the fires, but his uncontrolled power causes the Mushroom Bomb to explode, releasing forces of death. Farmworld Finn manages to save his donkey and his family, but realizing how dangerous he has become, sends them far away to safety.
In the Time Room, Prismo reveals to Jake that Finn has been transported to a separate, altered world based on his wish that The Lich never existed. Together, they watch the events in Finn's world on Prismo's television, and Prismo asks Jake what he would like to wish for. Jake wishes for a sandwich, but Prismo urges him to use his wish on something important, such as helping Finn. Prismo goes so far as to simply make Jake a sandwhich along with a jar of pickles so as to not waste his wish. However, Jake is nonchalant and states that he thinks Finn will be fine and that they should just see how things carry out. Instead, he and Prismo mute the television screen and spend their time hanging out in the Time Room, talking about relationships and why Prismo chooses to be single. They are joined by the Cosmic Owl who also hangs out with the two of them in Prismo's jacuzzi.
Meanwhile, Farmworld Finn's deepening madness is halted when he hears Farmworld Jake barking. He runs to the centre of the blast from the Mushroom Bomb where he finds Farmworld Jake half submerged in a pit of goo. He also finds a skeletonized Farmworld Marceline who says that she told him this would happen, before dissolving into the goo. Grotesquely transformed by the goo's power, Farmworld Jake begins to advance on Finn.
The Cosmic Owl accidentally unmutes the television and Jake hears Finn's plea to Farmworld Jake to recognize him as Farmworld Jake changes into a giant Lich-like monster. Alarmed, Jake finally listens to Prismo's advice to use his wish to save them. Jake wishes that Finn will be safe, but Prismo stops him, stating that because he likes Jake, he will reveal that according to the rules, the wishes he grants always come with ironic consequences: being unspecific could make a well-intentioned wish turn out terribly. For example, if Jake wished for a backrub, the person doing it could be undesirable, terrible at it, or transported away from their family in order to perform it. Wishes also affect both the past and the present: worlds could be unmade, babies would be unborn, memories could be erased and potential worlds evaporated. He explains to Jake that the trick is to be very specific about all parameters of the wish to ensure that it makes the desired outcome.
Jake starts to crumple under the pressure, so Prismo directly instructs Jake into making the one wish that can fix everything and return him and Finn to Ooo and also puting an end to the Lich for good: wish to change the Lich's wish from wishing all life to go extinct to wishing that Finn and Jake would be returned home to Ooo and the Lich destroys himself by blowing himself up in the deep space, not in the Time Room here.
Prismo grants his wish and time is reversed to the moment the Lich makes his wish. He instead wishes that Jake and Finn were returned home and he destroys himself by blowing himself up in the deep space, and is immediately shocked, as he knows this isn't what he wished for. Prismo cuts him off and tells him that he already made his wish and everybody only gets one. Prismo then points out to the observing Jake that thus even the Lich's wish resulted in an unintended outcome for the Lich. As Finn and Jake disappeared, the Lich is sent into deep space as he yells, "NOOOOO!!!" and then he blows himself up, thus the Lich is finally destroyed for good.
Finn and Jake return to Ooo moments after they entered the portal and Finn is confused, no longer having experienced the Farmworld from his own wish. Finn is alarmed and confused as to why the Lich wished them home and also wished for destroying himself for good, but Jake is overjoyed, telling Finn and Princess Bubblegum that everything already happened and that he fixed it and saved them all. The jewels used to open the portal return to their respective crowns, including Hot Dog Princess, Embryo Princess, Lumpy Space Princess, and Ice King, who is "penguin shaming" Gunter to get him to reveal what he did with his jewels. Finally, Prismo sends Jake a jar of pickles with a note saying that anytime Jake wants to hang out, to give him a call. Jake resolves to find Prismo a girlfriend.