After waking up alone and shipwrecked, Finn investigates a bizarre island in search of his friends.
Tropes:
- Accessory-Wearing Cartoon Animal: The giant animals inexplicably all wear shoes.
- Brutal Honesty: Finn repeatedly describes Susan as smelling bad.
- Description Cut: Jake says it should be easily to find BMO and Susan on the other islands. Cut to BMO, apparently on the moon.
- Giant Enemy Crab: Jake is found fighting an enormous crab.
- Gone Horribly Wrong: The various anomalies of the island were created by a group of scientists for presumably beneficial purposes, but wound up running wild and killing almost all of their creators.
- Happier Home Movie: Alva's film shows when she was young and researched on the island, but quickly takes a turn for the worse.
- Insane Troll Logic: Finn very seriously questions how crabs and robots are not the same thing.
- Isle of Giant Horrors: The island is full of giant version of various animals, most of which are hostile.
- Late to the Tragedy: Finn discovers humans lived on this island, but the harsh weather and giant animals has already killed everyone but Alva.
- Soft Water: Finn gets hit directly by a tidal wave, but doesn't even budge from the cliff he's hanging off.
- Terrible Artist: Alva asks Finn to draw her after seeing a good sketch in his notebook. That's not actually Finn's picture, and the ones he makes of Alva, Jake, and Susan are all incredibly crude.
- Weird Weather: The island experiences radical shifts of weather, with exact cut off between regions that are freezing and burning hot.
- You Have No Idea Who You're Dealing With: When a bear shows up, Finn is unimpressed and boasts of fighting the Lich in the Citadel.