sophie
Break My Heart
Are...are those good starting points? I feel that it it would be impossible for me to penetrate the thicket of lore that's been built up by this point.
They're good starting points for the lore itself; what the background of the universe is. They're also ostensibly the best episodes of the whole show.
Beyond that all you need to know is Finn is a dumb kid who likes adventuring and Jake is his very lazy dog/brother who can change himself into any shape he wants. Because magic (or "magic").
Also there are candy people. And vampires. And demons.