Season 5: the new season will premiere March 2013 with Zach Shada joining the cast as a new character .
1-2. New Brother
When Finn discovers a secret about his past before Jake's parents adopted him he set's off to find his long lost 18 year old brother Pen from The Ice King.
New Stars:Zach Shada - Pen
Notes : It is revealed Finn & Pen's last name is Mccall and Jake's last name is Burls.