Tap-Tap

Tap-Taps are small, spike-covered enemies that walk back and forth in Super Mario World 2: Yoshi's Island and its remake Yoshi's Island: Super Mario Advance 3. Sometimes they'll hop up and down. They can't be hurt in any normal way, except for an egg. A Huffin' Puffin chick will send one flying backwards, and if it hits another, the other one will be destroyed. They're immune to most attacks, except ice breath and fire breath. A Tap-Tap is encountered as a mid-boss in Super Mario World 2: Yoshi's Island as Tap-Tap the Red Nose, as well as a similar obstacle in Baby Bowser's castle known as Tap-Tap the Golden.

Tap-Taps have also appeared in Yoshi Topsy-Turvy, Yoshi Touch & Go (whose manual erroneously labeled them as Spiked Fun Guys, which are actually a different species), and Yoshi's Island DS, where they behaved similarly; however, instead of the normal ones walking off platforms, the pink ones walk off while the normal ones stay. A large, invulnerable variation (with the ability to crush land platforms) known as the Super Big Tap-Tap also appears in Yoshi's Island DS.

Trivia

 * The name of Tap-Taps may come from the distinctive clicking noise they make as they walk.