Flipper

The Flipper (, Spinning), sometimes referred to as the Bumper by fans, is a projectile item in Super Smash Bros. Melee and also a stage hazard in and Super Smash Bros. Ultimate.

Origin
The flipper originates from the game, Balloon Fight. In Balloon Fight, if a player bumps into a flipper, it starts to spin. If a player or enemies hits the flipper while it's spinning, the player temporarily flies out of control. After awhile, the flipper stops spinning.

As an item
The Flipper acts as a projectile item which can be picked up and thrown. After the Flipper travels a certain distance, it stops in midair. When hit, it spins either slowly or quickly (depending on either the speed of someone who has contacted it, or the strength of the attack), blocking passage and causing light (though generally repeated) damage when touched. After a certain period of time, the flipper will slow down and eventually stop spinning. The Flipper will disappear after about ten seconds have passed.

When used on moving stages (such as Big Blue, Rainbow Cruise, etc.), the flipper will continue to move with the background instead of remaining stationary. This is most apparent on Big Blue, where the flipper hangs still for a split-second, then races off screen as the Falcon Flyer and racers speed away from it.

Due to having near-identical usages and effects, the Flipper serves as Melee's equivilant of the Bumper from the original Super Smash Bros. game. This is further supported as the Bumper is the only item which didn't return from Smash 64, as well as the Bumper's return and Flipper's absence in Brawl, combined with Bumper's new ability to be set in midair being identical to the Flipper's. Furthermore, when Masahiro Sakurai revealed the return of the Bumper for Super Smash Bros. 4, he stated "This also means there will be no Flippers," an official confirmation that the items were intended to fill the same niche and not appear in the same game together. As such, the fandom often considers it and the Bumper as the same item.

Angle
The hitbox of a set Flipper uses a unique knockback angle of 362, which is not used by anything else and has never reappeared in any later game. Its behaviour is to knock the victim away from the hitbox based on the direction between the point of impact and the center of the damaged hurtbox. Because these factors can be difficult for players to perceive, especially if the Flipper is rotating quickly, it can appear like this angle is fairly random. But in general, this means that dropping onto a Flipper from above will try to knock the character upward, while jumping into one from below will try to knock back downward.

As a stage hazard
Multiple Flippers appear on Luigi's Break the Targets stage in Melee. Uniquely, these Flippers do not remain stationary in midair as the do in item form; instead, they move in random directions across the stage. Otherwise, they function the same as they do as an item.

Although Flippers are not items in Smash 4, multiple ones appear as stage hazards in the Balloon Fight stage in. Similar their effect as an item, they will knock players upwards to the left or right (depending on the direction they hit it) and deal 1% damage. Unlike in Melee, it'll only knock players left or right. In Ultimate, Flippers once again appear as hazards on the Balloon Fight stage, functioning the same as they previously did on the stage.