Nurgle

Nurgle is the name given to a malevolent, demonic alien-being in the Warhammer 40,000 universe - he is one of many chaos-gods and alongside his "brother" entities Slaneesh, Khorne and Tzeentch makes up the four primal gods of Chaos, who are considered the most powerful of all the many chaos deities: these alien beings are, unsurprisingly, the object of worship by the forces of Chaos and seek to destroy the mortal universe and replace it with their own twisted version of reality.

Nurgle is the chaos god of death and destruction as well as stagnation - most famous for his legions of diseased followers and minor-demons, which are shaped in his image and are known as Nurglings - an army loyal to Nurgle is a disgusting sight with his followers taking their horrible conditions as a twisted "blessing" and despite his evil nature Nurgle is often considered the most paternal of the chaos gods who watches over his followers like children: though like all chaos deities he is a twisted god whose blessings are hazardous at best and downright sadistic at worst.