|The following information is from the Adventure Time comic book series.|
It may not be part of the same canon or continuity as the animated series.
Issue 34 of the Adventure Time comics.
"Finn has made it to Magic Man at last! It's time for this adventure to end and for Finn to finally get his memory back. It might seem like an easy end, but it looks like there is still one more trick up Magic Man's sleeve."
Comic preview pages and panels