F.L.U.D.D. (ポンプ Pump), short for Flash Liquidizer Ultra Dousing Device, is Mario's down special move in Super Smash Bros. Brawl and Super Smash Bros. 4. The move involves Mario taking out F.L.U.D.D. and charging it up for about a second and a half. Pressing the button while charging, or using the move after being fully charged, results in F.L.U.D.D. firing twelve globs of water a distance dependent on the charge. The attack does not deal any damage, instead simply pushing opponents based on the charge level. The water spray can be aimed vertically with the control stick. Like other such moves, pressing a shield button while charging will cancel and save the charge, while getting hit during charging will lose it. Should Mario use the move in the air, he will be pushed backwards.
In most situations, being pushed by F.L.U.D.D. is merely a nuisance, not doing much but forcing combatants apart. When used judiciously, however, F.L.U.D.D. can be highly effective. Opponents that are attacking will clang with each segment of the water stream, trapping them in significant freeze frames and possibly allowing Mario to approach. More notable is the move's power at gimping - as it deals no damage and doesn't cause the opponent to flinch, it can push opponents away from the stage during their recovery without giving them another chance to use it, often not only further distancing them from the stage but providing momentum in the wrong direction.
It was noted on the Dojo that this move can be charged while shielding; however this is not true, as shielding merely saves the current charge.
F.L.U.D.D. originally appeared in Super Mario Sunshine for the Nintendo Gamecube. Mario encounters the device at the beginning of his vacation and is then forced to use it to clean up the pollution on Isle Delfino. Although its main use is to wash away poisonous goo, F.L.U.D.D. doubles as a weapon and can be used to push small enemies away or stun them. If the water tank emptied, Mario is required to refill it in the nearest source of water. In Brawl, F.L.U.D.D. uses the secondary purpose from SMS as a defensive measure against opponents. Unlike Sunshine, Mario can fill his tank with water anywhere, though the animation is fairly similar.
 Aqua Jump
An aqua jump occurs when Mario's FLUDD or Squirtle's Water Gun hits any jumping character just before they begin to lose momentum. This causes the jump to rapidly speed up and double in height. It is technically not so much of a technique as a misuse of the two aforementioned moves.
 Trophy Description
A multifunction water cannon invented by Professor Elvin Gadd that Mario totes like a backpack. Since F.L.U.D.D. is able to converse with Mario, it's believed to be equipped with some kind of artificial intelligence. With special nozzles, F.L.U.D.D. can be used like a jet pack to reach high places or for high-speed swimming.
"Press B once to prime, then again to shoot water that pushes foes (no damage)."