Enemies + Goombas
The roster for Mario enemies are constantly expanding. For every new game, there is at least 1 new enemy. The most well known is probably either the Koopa or the Goomba. Most of these enemies a minions of Bowser. He's basically a much bigger Koopa with a spiky shell and can breathe fire. Mario enemies can actually use two of Mario's powerups. These are the Cat power-up from Super Mario 3D World, and the Tanooki suit from Super Mario Bros. 3.
Goombas are the first enemy you see in the original "Super Mario Bros.". His tactics are to walk around aimlessly and hope to get Mario. They don't pay much attention because they don't go after Mario, but just keep walking unless there is a wall. They will even fall off the side.
Goombas are the first enemy you see in the original "Super Mario Bros.". His tactics are to walk around aimlessly and hope to get Mario. They don't pay much attention because they don't go after Mario, but just keep walking unless there is a wall. They will even fall off the side.
Piranha Plants
Piranha Plants are similar in looks to a venus fly trap. They pop up from pipes and try to eat Mario. Here's a tip to get past them: since they pop out every once and a while, just stand next to the pipe and they won't come out. This also works when you're on top of it. Some Piranha Plants can even breathe fire that goes through everything and illuminates the surrounding area of the fireball.
My Personal Favorites:
The Dry Enemies
This is probably what you aren't thinking: "What was that gray thing in the slideshow?" Well that was just one of the "dry" enemies. Dry is basically their word for dead. This handsome fellow (left) is a Dry Bones, the most common dry enemy. These guys, or girls, can't be defeated unless you freeze them and chuck them at a wall. There are also other kinds of dry enemies: Dry Bones, Dry Goomba, Dry Bowser, Dry Piranha Plant, Dry Buzzy Beetle (like Koopas, but on all fours), and more. Dry Bowser is Bowser, but not. He's his own character and not just a skeleton of Bowser. His first appearance was in "New Super Mario Bros." for the DS. He makes other appearances as well.
Birdo:
This....thing is named Birdo. She, I mean "it", is similar to Yoshi. She was a boss in Super Mario Bros. 2. She can shoot eggs out of her face and is the girlfriend of Yoshi. Birdo was actually considered male in her/his first appearance. It was then proven that Birdo was, in fact, female. She mainly appears in the spin-off games. Most of the time she is Yoshi's partner in games like Mario Tennis, or Mario Kart Double Dash!!