Astror bin Albert Machmud Usāmah bin Muhammad bin 'Awad bin Lādin Admiral General Haffaz von Aladeen Darth Sidious Nurgle, also known as the "Plague Lord," "Grandfather Nurgle," the "Plague God," the "Lord of Pestilence," the "Fly Lord," "Plaguefather," and the "Lord of Decay" among many other honourifics, is the Chaos God of disease, decay, despair, destruction, death and rebirth. In particular, the emotion of despair in mortals empowers the Plague God more than any other.
Astror was the third of the Chaos Gods to fully awaken within the Warp, emerging during the 2nd Millennium in the midst of Old Earth's European Middle Ages, as great plagues swept across the world heralding the god's birth.