Spinner

A Spinner, originally known as Ball 'n' Chain, is a spiked ball on a chain first appearing in Super Mario World. They are usually found in castles, and are indestructible. In most games, Mario can safely pass through the chain unharmed.

Super Mario World
Spinners first appear in Super Mario World, in castles and fortresses. Also, using a Spin Jump will allow Mario/Luigi to harmlessly bounce off the spiked ball. The only way this obstacle can be defeated is using a star, but its sprite will change into a defeated Bony Beetle, as it was never programmed to be destroyed.

New Super Mario Bros.
Spinners reappear in New Super Mario Bros.. These obstacles are very rare, with their only appearence in the World 7-Castle. The blocks are still there, and one even has a Star Coin. As an added feature, they rotate wildly on the end of the chain as well as spinning on the block; however, this does not affect their attack.

New Super Mario Bros. Wii
Spinners reappear in New Super Mario Bros. Wii once, in Lemmy's Fortress and in a secret area of Wendy's Castle. However, like in Super Mario World, they can be defeated using a Super Star.

Super Mario 3D Land
In Super Mario 3D Land, Spinners appear in purple with yellow spikes and chain. This time they are not linked to shackles, like in Super Mario World. Instead of spinning, they only make pendulum movements. They can be destroyed by making contact with them as Statue Mario.

New Super Mario Bros U
In New Super Mario Bros. U, regular and giant Spinners appear, swinging in a pendulum-like manner as they do in Super Princess Peach and Super Mario 3D Land. Unlike other iterations, however, these Spinners cannot be avoided by passing through the chains, as they have been spiked too.

Super Mario World television series
A Spinner makes a brief appearance in the Super Mario World animated series episode "Send in the Clown". Mario, while traveling through Neon Castle, narrowly avoids being hit by a Spinner that drops from the ceiling as he traverses over some lava.

Super Mario World 2: Yoshi's Island
Spinners reappear in Super Mario World 2: Yoshi's Island. They are colored red instead of black, they are usually found in fortresses. This is the first game which they have spikes on their chains.

Yoshi's Story
Spinners reappear in Yoshi's Story where they either swing in a manner similar to pendulums or quickly drop down to the floor and then slowly rise again. They only appear in the levels Tall Tower and Magma Castle.

Yoshi's Island DS
Spinners reappear in Yoshi's Island DS. Their behavior remains unchanged.

Yoshi's New Island
Spinners reappear in Yoshi's New Island. Their behavior remains unchanged.

Yoshi's Woolly World
Spinners also appear in Yoshi's Woolly World. This time, they are colored black instead of red. Their behavior remains unchanged.

Mario Kart 8
In Mario Kart 8, a single Spinner appears as an obstacle in Bowser's Castle. The obstacle acts virtually the same as the pendulums in Tick-Tock Clock. Also, the Spinner moves faster during the final lap of the course.

Mario Party 10
Spinners reappear in Mario Party 10 in the minigame Spiked Ball Scramble, this is also their first Mario Party appearance.

Mario & Luigi: Partners in Time
Spinners make a minor appearance in Mario & Luigi: Partners in Time only found in Bowser's Castle in the background.