The Fear Feaster makes his appearance in the episode "Ocean of Fear." He first introduces himself as the manifestation of Finn's fear, but Finn and the Three Wise Men later call him the Fear Feaster. He appears to live inside Finn's stomach and emerges from his bellybutton when Finn realizes that he is afraid of the ocean. He mentions repeatedly that he hates this arrangement, as Finn's guts aren't very pleasant. The Fear Feaster is defeated when the Three Wise Men—who appear to be similar kinds of entities—emerge from Finn's belly and convince him that he is still a hero. After his defeat, the Fear Feaster is banished back into the depths of Finn's guts. Finn said to the Fear Feaster, "Everybody has a flaw, and it looks like yours is smelling like my nasty guts."
The Fear Feaster makes his final appearance in "Billy's Bucket List," where when Finn tries to complete Billy's bucket list,
he is turned away by a wave (similar to "Ocean of Fear"). After Finn knocks himself out and he has his dream, he wakes up, and, to his dismay, he's in the ocean. After the Fear Feaster says his final line "Wake Up... WAKE UP! [evil laugh] No Mortal blade can harm..." Finn's sword takes control of his body once again and slashes through the Fear Feaster, cutting him from Finn and ultimately destroying him. Very soon after, Finn realizes that he is not afraid of the ocean anymore.
The Fear Feaster is a gaseous being of a deep blue to black coloring. His eyes have no pupils and are a grayish blue, he appears to be missing a few teeth, and though he has no nose there are holes which simulate nostrils. Fear Feaster also has a black mustache. His face is similar to the Evil Ocean's.
Ha! You are too scared of the ocean to ever be a true hero!
Of course you will, and I live in a two bedroom apartment, that doesn't smell like vomit (laughs) sarcasm.
(laughs) Pathetic! You can't even overcome your fear now that your friend is about to die! Your unheroic body will never let you save Jake! (laughs)
You've nothing to be proud of, boy! You will never get over your fear of the Ocean!
- The Fear Feaster represents one of the four humors, black bile.
- The Fear Feaster is featured as a special attack in the game Break the Worm.