Finn, Jake, and Susan set sail on a ocean voyage full of wonders and danger.
Tropes:
- The Bore: Whipple drives people crazy by talking about his terrible ideas for stories.
- Bystander Syndrome: Finn wants to help Whipple, but Jake doesn't want to go off course and Susan (wrongly) thinks the sailors have a good reason to hunt him.
- Continuity Nod:
- Finn defends his poor navigational skills by pointing out he's been afraid of the ocean most of his life.
- Finn mentions how Margaret found him as an infant in "Memories of Boom Boom Mountain".
- Tree Trunks' connection to the ancient magma elemental Magwood from "Evergreen" is further established by showing an island where a cult of tiny elephants breed elephant-like magma elementals from a volcano.
- Derelict Graveyard: The Colossus of the Deep's domain is signaled by an Ominous Fog around a bunch of broken ships.
- Disappointed in You: Jake's hallucinations of his parents guilt trip him for not being able to overpower Finn and Susan.Fake Margaret: Remember we love you!
Fake Joshua: Even though you're really letting us down! - Disproportionate Retribution:
- A bunch of sailors attack Whipple because "[he makes] us uncomfortable".
- Whipple destroys Princess Bubblegum's ship either because everyone thought he was boring or because they lied about it (Finn's not sure which).
- Do-Anything Robot:
- Dungeon Bypass: When Whipple really wants for the party to make it to their destination, he uses his wind power to blow their ship over all the dangerous obstacles, including the poison reef, a waterfall in the middle of the ocean, and a bunch of spikes that come out of the water. However, he couldn't get them past the hardest obstacle—the Colossus guarding the island.
- Heel Realization: Whipple destroys the ship of the sailors who attacked him, and the sailors admit that "we deserved that" as they go off in their lifeboats.
- I Don't Like the Sound of That Place: Jake plots a course through the "Sea of Sure Death".
- Ironic Echo Cut: After Whipple offers to take them to the island, Finn tells him "Whipple, you're the greatest." Cut to hours later where Whipple recounting a terrible story he wrote and Finn desperately whispers "Whipple, you suck so much."
- Little Stowaway: BMO reveals they stowed away, and bursts out when they're tired of listing to Whipple.
- Living Ship: Whipple destroys the Sugar Spit, so Jake implements his backup plan of being the boat.
- Puppeteer Parasite: Some jellyfish attach to Jake and make him see hallucinations that steer him toward a poison reef. One gets on Susan and makes her see a child in an animal hat she doesn't quite recognize.
- Quest for Identity: When Jake wants to turn back, he questions why Finn cares so much about humans, asking if he'd rather live with them instead of his friends. Finn doesn't, but feels he needs to find out about them anyway.Finn: OK, look—I'm really happy in Ooo. I love our mom and dad, but I don't know squat about humans. If I don't see this through, part of me will always be to stuck to that Boom Boom Leaf where mom found me... still alone.
- Weather Manipulation: Whipple can create storms, winds, and whirlpools.
