Barney Bubble

A Barney Bubble is a round purple creature that spits out bubbles when stepped on in Super Mario World 2: Yoshi's Island. Its name is a pun of Barney Rubble from The Flintstones. There are two in the game, and they only appear in the Monkey's Favorite Lake level. They run back and forth quickly. Jumping on one will make it spit bubbles. Grabbing their bubbles with his tongue lets Yoshi spit out more bubbles. The enemies would not be a threat, but the two in the game are found in a tight hallway where they are hard to avoid. They cannot be eaten, and must be taken out by using an Egg. Also, in Yoshi's Island: Super Mario Advance 3, there are two more added in the World 6 Secret, Endless World of Yoshis.