Bullet Bill

Bullet Bills (, Killer) are enemies from the series.

Origin
Bullet Bills made their debut in Super Mario Bros. as a common enemy, and has become a common enemy in later Mario games. They are black missile-like enemies with scowling eyes and white arms with clenched fists.

Bullet Bills are often shot by Bill Blasters, though in rare cases they appear on their own. They quickly fly in a straight line, damaging the player on contact, but they can be easily defeated by jumping on them. In  and in later games onward, Bullet Bills can home in on the player.

Since ', Bullet Bills have become a recurring item in the ' series. When used, it will transform the player into a giant Bullet Bill that increases their speed for several seconds and places them in autopilot, knocking over any of the opponents along the way.

The Bullet Bills feature larger versions: Banzai Bill and.

In Super Smash Bros. Melee
Bullet Bill was mentioned in the Banzai Bill trophy description, which was misidentified as Bullet Bill prior to the PAL and 1.02 NTSC releases.

As an enemy
They fly from offscreen, exploding upon impact with a character or on the ground. They also appear in and 's introduction, in which three of them are destroyed by Diddy Kong. They can be reflected, but will often quickly recover and continue their attack. Some of them are homing, following players until they hit. Unlike in the Mario games, Bullet Bills cannot be defeated by jumping on them.

As an item
Use this item to transform into Bullet Bill and shoot straight at the enemy. Your Circle Pad or Control Stick input at the moment you trigger the item will determine your launch direction, after which you'll fly in a straight line. The Bullet Bill debuts in Super Smash Bros. 4 as a transformation item.

Bullet Bills appear on the ground and can be picked up. When used, instead of throwing the item itself, the user transforms into a large Bullet Bill and flies in a straight line in whatever direction the control stick/circle pad was pointed in on release. Upon traveling about the length of, the user returns to normal, and will recoil backwards to help with returning to stage unless they have aimed directly upwards. The Bullet Bill does 25% damage and delivers high knockback that can KO under 80%, but firing oneself directly downwards or towards a blast zone can cause a self-destruct. If the bullet hits a solid surface, it will produce an explosion that deals 30% damage. It is possible to drive the bullet into the floor with an opponent in between so that the bullet and explosion hit consecutively, dealing a total of 55% damage.

Notably, where the Bullet Bill can be directed is not limited to the cardinal (up, down, left, right) or intermediate (perfect diagonal) directions and can be aimed between such, allowing for more accuracy when using the item. Additionally, the player is considered a projectile while transformed into a Bullet Bill, meaning characters with reflectors can simply make the Bullet Bill fling back in the direction it came from while damaging the user in that form or attacks with priority will nullify the Bullet Bill and cause it to pass through the attacker, but it can still do damage afterwards.

Humorously, the user is forced into their reeling animation once the Bullet Bill transformation ends, although this is cosmetic and can be cancelled into anything else, such as an attack or jump.

As an enemy
Bullet Bills also appear as enemies in Smash Run in, reprising their behavior from Brawl, although they can no longer be reflected. They deal 3% damage upon impact, or more if they collide with a surface and explode. In addition to being found on their own, they can also be fired from Bill Blasters, in which case they do not home in on the player.

A large number of Bullet Bills can appear as a random event.

Bullet Bills appear as part of the -themed Vs. Enemy Team final battle, where some of them fly forward like as if they were shot out of a Bill Blaster rather than homing in on the player.

As a background character
In, Bullet Bills appear as background characters in the Super Mario Maker stage. Their appearance changes depending on the game style, matching their designs in Super Mario Bros., Super Mario Bros. 3, Super Mario World, and New Super Mario Bros. U.

Trophy
The Bullet Bill trophy appears in both versions. In, it is part of the Bowser's Minions.

As an item
The Bullet Bill returns as an item, reprising its behavior from Smash 4.

Spirit
The Bullet Bill also appears as a Novice-class primary spirit.

In Adventure Mode: World of Light, the Bullet Bill is presumably one of the countless spirits captured by Galeem during his takeover of the universe. The Bullet Bill's spirit appears in the 8-bit maze area of The Light Realm.

The Bullet Bill Spirit Battle uses an army of puppet fighters and is fought on the  stage. During the battle, the Bullet Bill items will appear in large numbers and the Captain Falcon Team will be distracted by the items.

Trivia

 * There is evidence within the game's scripts that the Bullet Bill item itself should be able to explode, however this does not appear to be possible in-game.