Galoomba

Galoombas (simply named Goombas in the English version of Super Mario World, Round Goombas, or Kuribons) are the Goomba variety featured in Super Mario World. During the Koopa Troop's invasion of Dinosaur Land, these spherical-shaped Goombas are deployed in large numbers. However, these creatures do not appear in masses as do their mushroom-shaped brethren (known as "Kuribō" in Japanese) during the events of Super Mario Bros. and Super Mario Bros. 3. Instead of Goombas, Koopa Troopas fill the role of common soldiers for the Koopa Troop. While some Galoombas are stationed in certain locations as guards, others are dropped from the sky in droves. They either parachute from above or float down in bubbles (which burst upon coming into contact with any object).

Super Mario World
Galoombas look and act notably different than Goombas. Although these creatures walk in straight paths to attack, like regular Goombas, these new baddies do not resemble the older ones. Galoombas do not have mushroom-shaped heads, but spherical ones. They also lack a stem: the Galoomba’s two feet are attached directly to the bottom of the head. As such, they resemble angry chestnuts more than scowling mushrooms.

Galoombas cannot be defeated in a single jump, as doing so flips them over and immobilizes them. In this state, they can be picked up and thrown at other enemies, like with Koopa Troopas. Running into them or jumping on them when flipped causes them to be kicked around. After a few seconds they right themselves, which damages Mario if he is carrying one. They can automatically be defeated with a Spin Jump, or with a fireball or an attack from Yoshi; an attack with the cape causes them to be flipped over as well.

In the Super Mario World Game Boy Advance remake, Super Mario World: Super Mario Advance 2, after the player beats the Special World and finds all of the exits, the Galoombas are colored yellow and wear sunglasses.

Super Mario 3D World
Galoombas have also been shown to appear in the upcoming Super Mario 3D World, alongside regular Goombas and a bigger variation named Big Galoomba. Like normal Goombas in 3D Mario games, they attempt to chase after the player upon seeing them. Like in Super Mario World, Galoombas cannot be defeated with one jump, as that causes them to be flipped over, though unlike Super Mario World a second jump defeats them. Additionally, Galoombas cannot be kicked around, as running into them while immobilized also causes them to be defeated.

Mario Party Advance
The Galoomba species are also seen in Mario Party Advance for the Gameboy Advance. There are two of them in the game, named Goombob and Goombetty.

Trivia

 * In Super Mario Galaxy and Super Mario Galaxy 2, Micro-Goombas have an appearance similar to Galoombas.