Mr. Blackteeth is a puppet and the main antagonist in the episode Slapstick.
Mr. Blackteeth tells Jessie that she could have the power to control her parents. Because Jessie is annoyed with her parents, she listens to Mr. Blackteeth and raps on her forehead three times and says "That's the way to do it." When Jessie does this, she turns her parents into living puppets and she has the ability to control them. In the end of the episode, it is revealed that Jessie can't turn her parents back to normal until she finds someone else who is annoyed with their parents and she will have to make them do the same thing.