Smudge is a member of Jaybird's gang in the episode "Apple Thief." In the episode, he is a big bodyguard who guards Jaybird's "apples." The only time he speaks in the episode is when he agrees with Jaybird to feed Finn and the others to Pig.
He is a ginger bread man with a white outline and 3 different colored buttons. His face shows a somewhat angry or displeased expression.