Shikotsumyaku (屍骨脈; Literally meaning "Dead Bone Pulse", Meaning (Viz) "Corpse Bone Chain") is the kekkei genkai of the extinct Kaguya clan, which gave them the ability to manipulate their own skeletal structure (their osteoblasts and osteoclasts). By infusing their calcium with chakra, they could manipulate the growth and properties of their bones to their liking. The ability seems to be rare amongst the clan members, as there were only a few to exhibit it out of his entire clan.
Ten-Digit Drilling Bullets
Hardened bones from the fingertips are shot at the enemy, with a spinning motion added to the skeletal bullets. A direct hit will excavate skin, flesh, and bone. Since the bones of the user can be regenerated, the rate of fire from the user's arsenal is limitless. This technique is essential to Obsidian for his long distance attacks.
Dance of the Willow
To perform this dance, Obsidian grows several long bone blades from his body for use as weapons. Though he primarily uses two blades grown from the palms of his hands, he also uses several secondary bones grown from his elbows, knees, and shoulders. This dance form is incredibly acrobatic, using spins, charges, and long sweeping slashes to make the strikes more effective and to evade opponents' counter strikes. He can also extend his bones to attack his opponents without having to adjust his own movement.
Dance of the Camellia:
Obsidian performs this technique by modifying the humerus (upper arm bone) of either his right or left arm to create a short, hilt-less bone sword. Since he can increase and compress the density of his bones, he can make the sword harder than steel. He then uses the sword to fight; his style uses quick cuts and thrusts to disable opponents quickly. He is extremely proficient with this sword and can, not only deflect shuriken, but also dispatch a large number of Shadow Clones with this technique
Dance of the Clematis: Vine
Using his kekkei genkai, the Shikotsumyaku, Obsidian can modify and pull out his own spinal column to use as a flexible chain staff, regrowing a new spine to replace the removed one. The protrusions on the vertebrae are modified to make them stronger and sharper. He would follow up with Dance of the Clematis: Flower to pierce the immobilized opponent.
Dance of the Clematis: Flower
This is a follow-up to the Dance of the Clematis: Vine. Obsidian's entire forearm is encased in a giant drill made of bone to attack the trapped victim. The bone is strengthened (through compression and its plaited spiral shape) to become the hardest type of bone the body can produce. The bone resembles a flower, hence the name.
Dance of the Larch
Obsidian uses this technique to create a mass of razor-sharp bone spikes all over his body. These spines appear to be branches off his pre-existing skeletal structure rather than completely new bones. He is even able to grow these bones at an extremely rapid rate so they can stab an opponent even as they are growing. He can even use them to block or trap an opponent's strikes. In addition to being an unwelcome surprise for opponents, it makes him basically untouchable at close range. If an opponent would start to get close to him, he would start to spin rapidly slashing the foe in multiple areas of their body.
Dance of the Seedling Fern
Obsidian's final dance (presumably the strongest as a last resort), this jutsu causes a giant forest of bone spikes to burst from the ground. Kimimaro is able to emerge from any bone at will, giving him a deadly element of surprise should the opponent be able to avoid the attack.
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