|The following information is from the Adventure Time comic book series. It may not be part of the same canon or continuity as the animated series.|
Adventure Time #36 is the thirty-sixth issue of the Adventure Time comic book. This issue features a back-up story titled "Grand Prize," which was written and illustrated by Michelle and Heather Nunnelly.
It’s the first Adventure Time starring its new creative team! With indie all-star Chris Hastings writing and the amazingly talented Zachary Sterling on art, these mathematical adventures are only going to get more algebraic!
Finn and Jake are at a portal, pursuing something that went through it. Jake is unsure about going in, so Finn motivates him with a playful insult. Jake does the same and they jump in, though Jake does realize the trick afterwards. They then see that they went to a space station on the moon. Finn starts having fun with the low gravity, claiming he can dunk on Jake now. However, neither of them notice that the skeleton of an astronaut is glowing red.
Back in Ooo, a strange witch by the name of Janice Bizzlethatcher goes to the ruined Temple of Arklothac and intends something big for Ooo. She performs a ritual with crystals that will send the moon into deep space. This irregular activity is picked up by the space station, which displays warnings on the monitors. Finn and Jake don't notice. Finn asks BMO (who is in his backpack) to connect to the station's computers. BMO refuses, saying they are "creeptacular." Jake remembers that they were chasing a monster. That monster, now possessing the astronaut's skeleton, jumps Finn from behind. Finn throws him off and he tries to get in Jake's body. Finn pulls him out and kicks him in the head. The monster in his true form, having fun messing with the duo, slips outside the station.
Finn and Jake say he is evil and must be destroyed. A flashback shows that earlier that day, the monster possessed a big sandwich they were about to eat and ran off. Currently in Ooo, Janice continues with her ritual, saying it is nearly done. The station continues its warnings, asking why no one is noticing. Finn opens the air lock to chase the monster, but Jake protests. It's too late and Finn is sucked into the vacuum of space. Fortunately, Jake, donning a spacesuit, puts him in another one. After Jake tells Finn to be more careful, they come across a "space dungeon." Going inside, they find a sword (the Blade of the Defender) that Finn instantly likes. Jake reads some writing on the wall and deduces that the sword only works as long as the user doesn't get hurt. Finn takes the sword, which shoots off lasers, claiming he won't get hurt again.
Suddenly, he is attacked by the monster, now possessing a statue. Not wanting to be touched, Finn destroys the statue with the sword's lasers, but the monster possesses the other statues all at once. Finn runs away, leaving Jake to get beat up. The monster says he wants to possess Jake, but that he can only possess non-living things. Before anything more can be done, Finn slays the monster with a sword laser. In the temple, Janice is about to summon Arklothac. Before she can finish, a stray laser hits the temple and her, and she is crushed by a large piece of crystal. It turns out that Finn is aimlessly shooting sword lasers on the moon.
In a preview of the next issue, Tree Trunks says she doesn't know how to bake a pie, to Princess Bubblegum's shock. Back in the space station, BMO calls the computer a liar, as the moon didn't go anywhere. Finn and Jake head back home to bury their sandwich, and Finn dunks the astronaut's skull before leaving.
Finn is sick and BMO thinks he might die. Jake tells them that he probably has a cold, but that he does have a fever. Worried, BMO tells Jake to get medication at the store while they make a special soup. Jake goes, but stops when he sees a competition, which a number of princesses are entering. The man running it announces it as Moo's pudding eating competition and the winner gets a grand prize. Jake decides to enter for the prize. He asks Lumpy Space Princess why she's entering, and she replies that there's free food. Jake states a princess can't eat more than him, to which Muscle Princess objects. The two do a special handshake, and LSP calls it lame. The competition begins and everyone starts eating. It goes by rather quickly, with Jake and Tree Trunks being the only ones left. Jake doesn't understand how Tree Trunks can keep going, but doesn't quit. Tree Trunks then says she's stuffed and goes home, and Jake is declared the winner. At home, he shows BMO the grand prize: a 50% off coupon for Moo's pudding. BMO asks Jake if he got the medication, and he realizes he forgot.