Stone (move)
From the Super Mario Wiki
Stone is an attack used by Kirby in all three Super Smash Bros. games. Kirby will use this attack only if the B Button is pressed while holding the Control Stick down. Once this is done, Kirby will transform into a random heavy object. He cannot move in this state, but he can't be hurt. However, nothing stands in the way of a grab attack. The attack is best used in the air, so that Kirby can drop down on the opponent. In the original Super Smash Bros., Kirby only turned into a rock. However, in the sequel, Kirby could change into different things: a Garbage Block from Panel de Pon, a pink rock (the original Stone from Kirby's Adventure) , a 100T weight, a spiked ball (bearing a similar look to a Gordo), and even a Thwomp.
