You create a suit of armor around your body which is made of bone. This armor is not normal as is completely made of bone, the users skeleton comes out of their body and then covers their outside layers while a second skeleton regrows inside their body. The users ripcage and chest protect their body as the skull covers and protects the head the the other bones protect their other parts. It is extremely durable being able to take multiple shots from people with Chakra Enhanced Strength with no damage or effect being done to the user. Fire and Lightning Release have almost no effect on the person being protected by the bones. A second ability this armor has is that with everytime someone hits it, it slowly absorbs the marrow from their body making their bones more brittle and easier to break