From WiKirby, your independent source of Kirby knowledge.
Stone-Spark is a Power Combo in Kirby 64: The Crystal Shards that combines the Stone and Spark abilities. With the ability, Kirby can spit out a rock, which is connected to him by a stream of electricity.
While the stone is out, it flies about the stage, generally following a rotating pattern around Kirby. It will bounce and ricochet off walls and other obstacles and, along with the spark leash, will damage any enemy it touches. Kirby cannot hover while the stone is out, but the stone will eventually move in and make contact with Kirby, breaking in the process. Kirby can also make the stone explode prematurely, damaging enemies caught in the blast.
Like the other abilities in Kirby 64: The Crystal Shards, this ability does not change Kirby's physical appearance in any way.