Cape Feather

Cape Feathers are a type of feather that transforms Mario and Luigi into Cape Mario and Cape Luigi in Super Mario World. As their caped selves, they can hover in the air and fly, similar to the Super Leaf's effect in Super Mario Bros. 3.

The Cape Feather also appeared in the Super Mario World TV series, in episodes such as "King Scoopa Koopa" and "The Night Before Cave Christmas." Mario seemed to be the only one to don the cape in the series.

The Cape Feather (although referred to as "Feather") was also used in Super Mario Kart for the Super Nintendo as an item a driver could collect from item boxes throughout the race courses. The Feather's effect was the ability to hop roughly double the height the drivers are normally able to, as well as cause them to spin when they do jump. This would be useful for jumping over barriers, as a quick and easy shortcut, and as well as for jumping over enemy projectiles.

In Super Mario 64 DS the Feather reappeared. However, this time if Mario obtained one he would be transformed into Wing Mario instead of Cape Mario.

Additionally, the Cape Feather was also made available as a secret item in Super Mario Advance 4: Super Mario Bros. 3. By scanning in the appropriate card on the e-Reader, the player could upload a Cape Feather into their inventory to use in the game. Cape Mario plays just like he does in Super Mario World, and can even defeat Dry Bones.

Trivia
In the beta version of Mario Kart 64 a Cape Feather was one of the items in the game.