Twirlip

Twirlips are a species of enemy appearing in the game Super Mario Galaxy 2. At first glance, they appear as white bud shaped creatures with two beady eyes. However, they will turn into a pink flower with a yellow center and spin around the area like a drill from time to time.

In their flower form, Twirlips can only be damaged by stomping on their heads. In their bud form, Mario or Luigi can use any attack method to defeat them. Yoshi can also eat a Twirlip but only while it's in bud form. They appear in a few galaxies, most notably in the Spin-Dig Galaxy. They are also fought on some Bonus Planets.

Trivia

 * Twirlip is an obvious spoof of a tulip, a type of red flower.