Roto-Disc

Roto-Discs   (also formatted as Rotodiscs, Roto Discs,   and Roto-discs ), or simply Discs, are Fire-Bar and Ball 'n' Chain-like obstacles that first appear in Super Mario Bros. 3. Roto-Discs are found orbiting gray or red orbs, on which it is possible for Mario or Luigi to stand. Roto-Discs are nearly invulnerable; they can be destroyed if Statue Mario lands on top of one. Duo-Roto-Discs can also be found, which consist of two Roto-Discs circling the central orb. If the player destroys one, the other will disappear.

Aside from Super Mario Bros. 3 and its subsequent remakes, the only other appearance of Roto-Discs is in the Mini-Mario course in Bowser's Castle in Mario & Luigi: Superstar Saga and Mario & Luigi: Superstar Saga + Bowser's Minions. As a throwback to the previous games, they are obstacles that will send Mario back to the beginning of the area if they connect with him.

In Super Mario World, Roto-Discs is was going to appear, but it was abandoned. They was replaced with Ball 'n' Chains.

Super Mario Land contains Kaitensuru Honō, fiery orbs that similarly orbit a block and share the same attack pattern.

Super Mario Land 2: 6 Golden Coins also contains an enemy known as a Guruguri in the Mario Zone, which behaves in a similar fashion.

Perfect Ban Mario Character Daijiten
''' クッキー 　ゴースト族 　きまじめ ゲーム　3 ''' 安全地帯て一息つにう 玉を中心に、クルクル回るファイア系のゴース卜族. 赤い玉の上はどんなときも安全地帯なので、ここでタイミングをはかって抜けていこう.

 Roto-Disc  Tribe: Ghost clan Disposition: Too serious Game appearances: 3 ' Let's take a breather in the safe zone ''Fire ghosts that spin around a ball. The top of the red ball is a safe zone at all times, so use this area to get out of the way at the right time.''

Trivia

 * In Wario's Woods for the SNES, activating a combo causes an energy orb to appear and refill Birdo's time gauge. The sprite used for the orb is the same as the Roto-Discs, only with a different palette.
 * A sign bearing "ROTO DISC" can be found in the 1993 Super Mario Bros. film. According to production designer, the Rotodiscs were imagined as the energy-conversion engines used in the electric Dinohattan cars.