Humba Wumba is a native replacement for Mumbo, in Banjo-Tooie. She controls the transformations as Mumbo now controls other things. She is an enemy to Mumbo and she tells Banjo and Kazooie that Mumbo is an "amateur". You must collect her 1 Glowbo in each world to be transformed into something. After you've already given her a Glowbo, you can then be transformed...for free !