Transformation: Adamantine Staff

This is a unique version of the Transformation Technique used by Monkey King: Enma.

Overview
Enma transforms himself into a staff that is as hard as a diamond. Taking advantage of this, Enma can clone himself to create a cage around his summoner in order to defend against attacks. Despite its hardness, Enma stated that he could still suffer pain from the Kusanagi wielded by Orochimaru. The hardness of the diamond also translates into destructive power, as it was powerful enough to effortlessly destroy Hashirama's wooden structures and, when extended, forcefully move Kurama to the borders of Konoha.

While transformed as the staff, Enma can have his claws or fangs protrude from it, adding an element of surprise and irregularity. Forged in the fire of battle, its at-will transformation-based attack and defence go beyond the scope of proficiency to attain the realm of shinobi "godhood".

Trivia

 * The concept of an extendible staff is based on the story of Sun Wukong/Son Gokū and his Ruyi Jingu Bang (lit. Compliant Gold Rim Pole; read in Japanese on'yomi as the "Nyoi Kinko Bō"). Like the original staff and many versions based off of it, it shares its golden-shaft ends.
 * A nyoi (lit. compliance), which can be translated as priest's staff but literally means as one (a person) wishes, is an auspicious decorative object associated with Chinese Buddhist rituals. It was made from bone or jade, with a head shaped either as a cloud or as a lingzhi mushroom, and had a slightly curved handle, but the production and use of these objects declined after the Tang Dynasty.
 * Vajra, which is in Japanese, is a mythical material that is said to be able to cut through any substance, but cannot be cut itself. In Japanese, the term is also synonymous with adamantine and diamond, while in other contexts, it is known as the thunderbolt of the Hindu Vedic deity, Indra.
 * This also references the original staff itself being known for its heavy weight and durability which can only be managed by the original Wukong/Gokū's strength (due to other weapons being wielded by him ending up broken beforehand), as the staff itself was made of a rare form of "black crow iron" as its base.