Blue Nose is the main character in the episode, "Sad Face." According to BMO, every month Jake's tail takes on a mind of it's own and leaves the Tree Fort. As the episode progresses, we see that he is actually a clown that works for the Traveling Mini Circus. His main goal in working there is to free Goralina, as she is being held there as a slave. At first, he is boed for his strange, old-time acts. He soon comes to the conclusion that the only way to truly free Goralina is to act like a normal clown, and so he does. After this, the Ringmaster still refuses to let Goralina go, so he begins to attack the Ringmaster along with his Employees as a more aggressive tactic. Doing so ends up freeing Goralina, which the Ringmaster and his workers did not like. Since Blue Nose is just a long serpent-like being, they yanked his body back after he ran away in order to confront him. But then one the light hit his "face," he became to squirm back to the Tree Fort and once again become apart of Jake.
He appears to be a worm like creature with clown makeup. He also wears an old hat and carries a red bag tied to a stick.
Blue Face takes on a very caring and old-timey personality. Even though he didn't formally know Goralina, he still planned to save her, because he felt her pain. He is old-timey in the sense that his method of becoming a better act involved performing all of these weird, bizarre acts that only people in old times may have enjoyed (according to the Ringmaster). At the end of the episode, we get one last glimpse of his caring personality when we see him smiling at Goralina hugging Squirrel Lover.
His clown make up is seen in the title screen.
At the end of the episode, his red makeup-frown turned into a smile, signifying that he may have had a real mouth.