When old friends and enemies suddenly reappear in Ooo, Finn and Jake have to abandon their work building a dungeon and try to save the day, but they might need some help.

"Originally published in single magazine form as Adventure Time 30-34"--Title page verso.

Finn and Jake try to stop a skeleton named Lich from destroying the Land of Ooo.

When old friends and enemies sudden make a resurgence in Ooo, Finn and Jake know that something is about to go down... Between building their own dungeon and saving the world, the heroes might be stretched too thin. If they can't save the day, then who can?

What time is it? Adventure Time™! Explore the magical world of Ooo with Jake the Dog and Finn the Human, along with the Ice King, Princess Bubblegum, Marceline the Vampire Queen, and all your favorite Adventure Time characters, in this New York Times bestselling companion book to Cartoon Network’s hit animated series. Written and compiled by the Lord of Evil himself, The Adventure Time Encyclopaedia matches the playful, subversive tone of the television series, detailing everything anyone will ever need to know about the postapocalyptic land of Ooo and its inhabitants—secret lore and spells, fun places you should visit and places where you will probably die, whom to marry and whom not to marry, how to make friends and destroy your enemies—plus hand-written marginalia by Finn, Jake, and Marceline. An indispensable guide to the show fans love to watch, this side-splittingly funny love letter to Adventure Time is sure to appeal to readers of all ages. Heck yeah! From the Back Cover: Written by the Lord of Evil Himself, Hunson Abadeer (a.k.a. Marceline the Vampire Queen's dad), to instruct and confound the demonic citizenry of the Nightosphere, The Adventure Time Encyclopaedia is perhaps the most dangerous book in history. Although seemingly a guidebook to the Land of Ooo and its postapocalyptic inhabitants, it is in fact an amusing nightmare of literary pitfalls, bombastic brain-boggles, and ancient texts designed to drive the reader mad. Complete with secret lore and wizard spells, fun places you should visit and places where you will probably die, advice on whom to marry and whom not to marry, and how to make friends and destroy your enemies, this volume includes hand-written marginalia by Finn, Jake, and Marceline. Arguably the greatest encyclopaedia ever written since the beginning of the cosmos, it is also an indispensable companion to humans and demons who know what time it is: Adventure Time! Praise for The Adventure Time Encyclopaedia: “Even if you’re an adult Adventure Time fan, the book will make you feel like you’re 10 again.” —USA Today’s Daily Candy blog “The brand-new Adventure Time Encyclopaedia will tell viewers everything they need to know about the post-apocalyptic magical land and its inhabitants.” —Entertainment Weekly’s Family Room blog “The . . . Encyclopaedia will appeal to Adventure Time fans who want to delve deeper into the show’s mysterious back story and bizarre details.” —The Los Angeles Times’Hero Complex blog

Finn is about to fall head-first into an adventure so intense, he'll never remember it! Finn tries to take on the Mnemonoid only to wake up in the future with no recollection what has happened in the time jump! With his pals Jake, Princess Bubblegum, and Marceline, Finn must remember how to beat this mean dude before he forgets everything else! Collects issues #30-34.