Blubi is a Nimbi that has a thick mustache. He also wears blue robes fitting his title as the "Blue Sage."
Blubi is first discovered frozen in ice in The Overthere. After Bowser frees him from his icy prison, Blubi is grateful but has amnesia. Fortunately, Luvbi manages to snap him out of it for a second and Blubi gives the Blue Orb to the heroes.