Dry Bones Shell
From the Super Mario Wiki
The Dry Bones Shell is an item in Super Mario Maker 2, available in the editor as an alternate object to Dry Bones. Unlike Buzzy Shells and Spiny Shells, Dry Bones Shells are upside down and cannot be worn on the head. Instead, they can be worn by Mario in a similar way to a Goomba's Shoe and are used to float across liquid hazards (including lava and poison), ground pound, and become invulnerable temporarily by turning into a pile of bones. Additionally, they can be kicked, though they break upon hitting a wall.
The Dry Bones Shell is the only possible means of Ground Pounding in the Super Mario World game style.
Super Mario Maker 2
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