Mini Goomba
Micro-Goomba is the name given to a species of small Goombas. Micro-Goomba is also called Mini Goomba and Gooms In Super Mario Bros. 3, some Paragoombas would drop Micro-Goombas onto Mario and Luigi, which highly weakened their ability to Jump temporarily. These debilitating pests were also known as Mugger Micro-Goombas. A similar species called Goombettes are found in Super Mario RPG: Legend of the Seven Stars.
They also appear in Super Mario 64's Tiny-Huge Island. They appear in the tiny side, and if they touch Mario, he will not get hurt, only knocked a few feet back, but the Micro-Goombas will die.
They reappear in New Super Mario Bros.. When Mario is Mini Mario, he can enter miniature pipes. If he enters one, Mario may find a Star Coin. However, in some cases, Micro-Goombas are in the way, and Mario has to bop them on the head to get to the Star Coin. In this game, Micro-Goombas possess the intelligence of any other Goomba, but can be more dangerous, because it only takes one hit to defeat Mini Mario.
In Super Paper Mario, Micro Goombas are not seen but only mentioned. A resident in The Underwhere mentions that he died all because of a Micro Goomba and a Bottomless Pit.