As a curling stone, Kirby will slide in the direction he was facing when he transformed and he'll freeze all foes in his path.[1]”
— Description • Nintendo Power (Volume #134)
Curling Stone[2] is a Power Combo Kirby gets by combining Stone with Ice, appearing in Kirby 64: The Crystal Shards. Kirby transforms into a curling stone, sliding around and bouncing off walls, as well as freezing any enemy he touches. Kirby will eventually slow down after he has slid a long distance.
In Kirby Star Allies, Curling Stone is referenced as part of a Friend Ability. When using Stone and in stone form, a friend can pass an element to transform the stone into a curling stone, carrying the given element. The handle color depends on the player (Kirby's is pink, Player 2's is yellow, Player 3's is blue, Player 4's is green), and the stone is given a silvery granite color. It has a star engraved on each side, and Kirby's face no longer has a mouth, but still retains his rose-colored blush. The Copy Abilities that can help Stone Kirby create the Curling Stone are Ice, Cleaning, and Water. Any character that can turn into a stone can become a Curling Stone; namely Stone Kirby, Rocky, Rick, and Gooey.
