Mari Mario

Mari Mario (マリマリオ) is an original transformation that only appears Super Mario-kun. Mario is turned into a ball and it's used as such in different occasions.

In chapter 1 volume 1, Luigi balls up Mario and tosses him to a Chargin' Chuck, but he tackles Mario towards a cliff.

In chapter 14 volume 2, while Mario lists all the transformations of Super Mario Bros. 3, he mentions Mari Mario, but Luigi points out that "he doesn't remember such transformation".

In chapter 8 volume 10, Mario is balled up by Roy and put into a flipper.

Trivia

 * An identical transformation would appear, without a name, in Mario Pinball Land.