From the Super Mario Wiki
Retrieved from "http://www.mariowiki.com/index.php?title=Boo_Balloon&oldid=2087278"
A Boo Balloon, also known as a Blue Boo, is a Boo in the shape of a blue balloon in Super Mario World 2: Yoshi's Island. They race about the screen, trying to deal damage to Yoshi. They will inflate when hit with a Yoshi Egg. After three hits, they will explode, yielding coins or sometimes a ! Switch.
Names in other languages