Pile Driver Micro-Goomba

Pile Driver Micro-Goombas, known as simply "Mini Goombas" in NES Remix 2, are a special variety of Micro Goomba that hide in Brick Blocks. They appear in Super Mario Bros. 3 and its reissues.

Super Mario Bros. 3
Pile Driver Micro-Goombas first appear in World 2-1, the first area of Desert Land, and are a staple enemy in the various desert and sky levels throughout the rest of Super Mario Bros. 3. They are disguised as grounded Brick Blocks that can be distinguished by the fact that they do not glisten (except in Super Mario All-Stars, which gave them a light-colored outline instead, but this was changed back in Super Mario Advance 4: Super Mario Bros. 3). When Mario or Luigi approaches their Brick Block, the Pile Driver Micro-Goomba moves slightly to show a pair of feet underneath the Brick Block, then jumps high in the air and attempts to land on the plumber to damage him. These enemies are resistant to fireballs and can be defeated by stomping, hitting it with a Raccoon tail, or by tossing a Koopa Shell at it.

NES Remix 2
In NES Remix 2, the Mini Goombas are featured as a Super Mario Bros. 3 challenge where the player has to defeat three off them in World 2-1 within twenty seconds.

The Adventures of Super Mario Bros. 3
Pile Driver Micro-Goomba-like monsters make one small appearance in The Adventures of Super Mario Bros. 3, in the episode "A Toadally Magical Adventure". Although they have similar characteristics and looks as Pile Driver Micro-Goombas, they are real Brick Blocks brought to life, and are only referred to "blocks". These blocks were created by Toad's Pipe Creatures after they rebelled against him.

New Super Mario Bros.
Although they are not related to Goombas, Blockhoppers from New Super Mario Bros. are fairly similar to Pile Driver Micro-Goombas in that they, too, hide in blocks. However, Blockhoppers can hide as stacks of blocks and also have the ability to mimic ? Blocks.

Super Mario 3D Land
Super Mario 3D Land also introduces Fake Blocks, similar enemies which have Tanooki tails they can whip with.