Nirmia was a small Eldar crafworld that was infected by the disease known as Rust in the later years of M.41. This resulted in their near destruction by the Necron Kharnakept dynasty . It is thought by the craftworlds healers and elders that the disease first appeared after the Eldar fought Chaos forces. Nevertheless, the Eldar were almost wiped out when the Kharnakept dynasty awoke to recliam their worlds. The Necrons fought the Eldar on their craftworld, destroying many Eldar. The craftworld was saved after the farseer Althran sacrificed himself to save the craftworld from the Necrons, but not from the disease. The craftworld itself is slowly dying as the infection slowly kills them.