Welcome to the universe's most mathematical guide to the Land of Ooo - written by Finn the Human and his bro, Jake the Dog! Read all about Ooo's kingdoms and residents, plus advice on how to be a true heroic adventurer. With sweet sections by Princess Bubblegum, BMO, Marceline, the Ice King and more, this righteous guide will make you the awesomest Ooo-expert that ever lived!