You are thinking of the episode 'Heat Signature', in which Marceline tricks Finn and Jake into believing they are vampires.
The episode "Evicted!" from the series Adventure Time is the 12th episode in season 1 and also the entire series.
It was on the episode 'Burning Low'.
"What Is Life?"
YES
the episode is called Freak City
The 2nd episode of Adventure Time is entitled "Trouble in Lumpy Space".
The episode "Evicted!" from the series Adventure Time is the 12th episode in season 1 and also the entire series.
no
It was on the episode 'Burning Low'.
267
"What Is Life?"
Time Sandwich
YES
Jermaine
Hoots
Be Sweet
Puhoy