Bullet Bill

Though not exactly an actual species, Bullet Bills are mechanical menaces that are extremely annoying.

In the game Mario Kart DS, part of the Mario Kart sub-series of the Mario universe, you can pick up a Bullet Bill as an item. After activating the Bullet Bill you will morph into one of these large, bullet-shapped creatures and rocket automatically down the track, knocking over any enemies or projectiles in your way. The Bullet Bill is unquestionably one of the best items in the Mario Kart series.

Bullet Bill is an enemy character from the Mario video game series. He is a large bullet that is fired from a cannon. Bullet Bill first appeared in Super Mario Bros. The only way he could be destroyed was by jumping onto it or running into it after obtaining the star power up. Using fireballs has no effect on it and there is no way to destroy the cannon.

Super Mario Bros.
Bullet Bill first appears in World 5-1. It is usually discharged from a large cannon, known simply as a Bullet Bill Blaster. On occasion, Bullet Bills will be shot from random locations somewhere offscreen.

Super Mario Bros. 2
Bullet Bills did not appear in the American version of Super Mario Bros. 2 by name, but there are similar missile creatures that are shot from Autobombs, which are ridden by Shy Guys. However, Bullet Bills were abundant in the Japanese game that was later released in the U.S. as Super Mario Brothers: The Lost Levels.

Super Mario Bros. 3
Bullet Bills didn't appear as much in Super Mario Bros. 3 as they did in previous games, mainly appearing in later worlds and on the bosses airships. A new type of Bullet Bill appeared in this games, the Missile Bill, that follows Mario.

Super Mario World
This game features the first appearance of Torpedo Ted's which are Bullet Bills that are launched from a device underwater. Banzai Bills also made their first appearance, which are larger version of a Bullet Bill.

Super Mario World 2: Yoshi's Island
This game introduces a yellow bouncing Bullet Bill that bounces and ricochets off walls after being fired. In the Gameboy Advance incarnation there are red Bullet Bills with gnashing fangs that home in on Yoshi.

Super Mario 64
Bullet Bill was only found in one location in the level Whomp's Fortress. In the levels after you defeat the big Whomp, a Bill Blaster will appear at the top of the fortress. The Bullet Bills shot out would home in on Mario. Bullet Bill cannot be defeated in this game.

Paper Mario
Gold Bullet Bills known as Bombshell Bills are introudced in Paper Mario, and appeared again in Paper Mario: The Thousand-Year Door.

Super Mario Sunshine
This game contained a Monty Mole that manned a cannon, firing Bullet Bills at Mario. These Bullet Bills are purple, with a red nosecone. They homed in on Mario and exploded after a short time. They could be destroyed with a burst of water from FLUDD. Rarely, Monty Mole would fire a golden Bullet Bill, which when destroyed, would yield extra coins. Bullet Bills were also fired by Mecha Bowser, one of the bosses at Pinna Park. Finally, in the final battle against Bowser and Bowser Jr., Bowser Jr. would fire regular black Bullet Bills and the occasional blue Bullet Bills, which when jumped on, gave Mario a 1-Up Mushroom or a water bottle.

Mario & Luigi
Superstar Saga: Bullet Bills and Bill Blasters returned as enemies at Stardust Field. The game also featued Sniper Bill, a large Bullet Bill that used a Super Scope as a weapon. It is found in Bowser's Castle.

Cameo Appearances
Bullet Bill has not appeared many spinoffs, other than occasionally as an enemy in a Mario Party minigame, or in the form of a baseball bat in early screenshots for Mario Superstar Baseball (note that Bowser's Power Shot is also a Bullet Bill). The Princess Peach's Castle stage in Super Smash Bros. Melee featured Bullet Bills as hazards. He also appeared in Mario Power Tennis in a mini-game, fired by a giant Bowser robot. The Bullet Bill item in Mario Kart DS transforms drivers into a large Bullet Bill, careening drivers through the course and into other characters for 4 to 7 seconds. Bullet Bills are also an obstacle in the Airship Fortress track of the same game.

Other minor appearances were an appearance on the last episode The Super Mario Brothers Super Show! and a Banzai Bill appears in the background of a Nintendo Revolution tech demo.