Fireball

Fireballs are small projectiles launched by Mario and Luigi by using their neutral B special moves. Each causes the minor damage and flinching common to fire-based attacks. In SSB, Fireballs were larger and more effective, decreasing in size for Melee and Brawl.

As with all standard specials, Kirby can also use Fireball after swallowing either Inhaled brother.

Mario
Mario's Fireballs fall to the ground, bouncing in accordance with the surface angle. As such, they are more effective when fired from higher locations and downward slopes, traveling greater distances. When firing at a wall or upward slope, the balls will bounce backward, a more defensive maneuver for brief protection from oncoming foes, perhaps in the air or from behind. Mario's fireballs can be spammed, though with some difficulty (and a slower rate of fire than Luigi), and are a decent approach tactic.

Luigi
Luigi's Fireballs travel in a straight line and are unaffected by gravity (matching his floaty motif). They are short ranged and spammable, and can be used at a slightly faster pace than Mario's, especially in the Negative Zone (Luigi's final smash). Fireballapproach is perhaps more difficult with Mario, as the attack does not fall when used in the air.

Origin
The Fireballs originate from the 1985 NES game, Super Mario Bros., where the ability was obtained by grabbing a Fire Flower. This would also change Mario's outfit to red and white, as it would to Luigi, except green and white. In the Mario Bros. game, red and green fireballs would occasionally appear to try and singe Mario or Luigi. The red fireballs moved in the exact same pattern as Mario's fireballs, and the green moved in the exact same pattern as Luigi's, although only the green ones appear in the actual Mario Bros. stage.

Trivia

 * In games such as New Super Mario Bros. and Super Mario Bros. Deluxe, Luigi used red fireballs that were both red and effected by gravity.