 " Walnuts & Rain " is the thirty @-@ first episode of the sixth season of the American animated television series Adventure Time . The episode was written and storyboarded by Tom Herpich , from an outline by Herpich , Adam Muto , Kent Osborne , Jack Pendarvis , and Pendleton Ward . The episode debuted on March 5 , 2015 on Cartoon Network , and guest stars Chris Isaak as a bear named Seven and Matt L. Jones as King Huge . 
