Hidden Stone's Kinjutsu is an unnamed forbidden technique passed down through generations in Iwagakure. It allows chakra to be kneaded into various materials, after which the object can be altered in shape, animated, and controlled at a distance. At the user's command, the size of such an object changes from tiny, almost invisible, to gigantic. After chakra is infused, the item is able to become a source for another technique.
Deidara stole this technique, seeking to find the supreme art, and combined it with his Explosion Release kekkei genkai. Thus he learned to infuse explosion-release chakra into clay, creating his signature Explosive Clay.