Goombas are iconic recurring enemies in the Mario universe. They appear in Super Mario Bros., Super Mario Bros. 3, and New Super Mario Bros. U styles. Instead, in the Super Mario World style, they are replaced by Galoombas.
It was shown that Goombas can be stacked up on eachother, forming a Goomba Tower.
Normally, they will walk around slowly, only damaging on contact and can be defeated with a single stomp, being very easy to kill, although there are variants of Goombas that raise the difficulty a bit.
If Goombas are added on a water surface, they will float around, chasing after Mario.
Adding Wings to a Goomba will cause it to move in a bouncing fashion rather than straight forwards. When jumped on, it first loses the wings, then it becomes vulnerable.