The material is also adaptive in some unknown fashion and can learn to repair itself given enough time from nearly any form of damage, even a blast powerful enough to reduce it to its constituent molecules or atoms.

Necrodermis is a material of unknown origin and chemical or molecular structure that possesses the extraordinary ability to regenerate almost all damage instantaneously, 'flowing' back together as if it were a liquid while closing bullet holes, mending gashes and tears, or even reattaching severed pieces with little delay.

This process transformed the Necrontyr into the undying Necrons. It was later adapted to create the robotic bodies possessed by the C'tan and inhabited by the Necrontyr after they agreed to have their consciousnesses transferred from their short-lived organic forms. Necrodermis is the xenos material created over sixty million standard years ago by the Necrontyr species that is often described as 'living metal.' It was originally used by the Necrontyr to construct their massive sub-light starships that explored and settled the Milky Way Galaxy millions of standard years ago. Necron bodies are composed entirely of necrodermis.

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