Metal Assimilation (金同化, Kin Dōka) is the perfected form of the Bu-Tai technique created by Ayame. The technique is performed in three steps. First his entire skeleton had to be scanned and re-built. An shikotsumyaku indo-skeleton was created and implanted into him. The second stage converts his skin into Haganekifu. The final stage involves draining the blood from his body and replacing it with a chilled saline solution. That blood is then treated and made into Laminanium. Which is then melted down and injected back into user. The Laminanium is key once injected it forms a symbiosis which not only binds user’s soul to the metal through their aura but changes hiss biological structure as his DNA is altered to DG27. Essentially the Laminanium, Shikotsumyaku, Haganekifu and the various other trace metals alloy and assimilates his body like an aggressive virus. His whole body is composed of DG27 meaning that he is seemingly invulnerable.
The user can also manipulate their body into objects of various shape or size relative to their mass. However, this can be compensated for as when combined with the the Secret of Steel this technique allows user to absorb nearby metals and integrating it into their body, giving the user the materials they need. This absorption has an additional, more advanced aspect to it: by absorbing metals, the user gains their abilities, traits, attributes and physiologies. This allows user to turn their body into much more complex shapes and forms, and even alter the density of their body.