Atropus

Atropus, known as the World Born Dead, is an undead planetoid whose coming was a harbinger of death and destruction.

Description
Once a great power, little remained of Atropus but a decaying, disembodied head the size of a small moon, apparently made of black stone, heavily cratered, and covered with foul amniotic fluid. It was barren and rocky, roughly spherical and with mountainous ridges, deep trenches, and sharp spikes upthrusting from the ground. Noxious tar bubbled up from the craters. Glossy black stones, each 40 miles in diameter, formed its eyes. The atropals—stillborn gods—were said to be cast-off detritus from Atropus's substance. Undead conjured from nightmares also inhabited the world, and the master of them all was a headless, alien humanoid that was the focus of Atropus's incomprehensible intellect.