Barney Bubble

Barney Bubble are round, purple creatures that, when stepped on, spit bubbles. They appear 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 appear only in the Monkey's Favorite Lake level. They quickly run back and forth. Grabbing their bubbles with Yoshi's tongue lets Yoshi spit more bubbles. 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.