Sceaduinar

Sceaduinars are a strange species of outsider native to the Negative Energy Plane and the dominant native species of that realm. Unlike virtually all other living creatures, they are based on negative energy rather than positive energy. Essentially alone in the multiverse and unable to truly create anything, they hate almost all other life forms.

Description
As outsiders, sceaduinars consist of the essence of their home plane, and their body and soul are one unit. Their life force - such as it is - consists of negative energy instead of positive energy, a trait they share with no other living creature except for a few related species. Because of this, they are immune to the lethal effects of the Negative Energy Plane but are harmed by positive energy, which heals more conventional life forms.

Anatomy & Physiology
Sceaduinars' bodies are entirely made of purple-black crystal. They resemble emaciated four-limbed gargoyles in general shape. Their forelimbs are wide, batlike wings, while their legs end in single points rather than digits or feet. Their heads resemble those of bats, and their mouth are filled with small, sharp teeth. These teeth serve mostly as weapons, since sceaduinars do not need to eat. Sceaduinars are about 7 feet tall and weigh around 100 pounds.

Diet
Sceaduinars do not appear to need food and are most likely self-sustaining as other outsiders are, fueled by the energy of their home plane - negative energy, in their case. They can drain the positive energy life force of normal creatures with their bite, but do not seem to actually need to in order to survive.

Reproduction & Life Cycle
Sceaduinars form spontaneously from crystallized entropy formations that congeal within the depths of the Negative Energy Plane. Fruit-like growths on these formations grow into fully fledged sceaduinars or related creatures. Sometimes this process occurs on its own, but it is often guided by other sceaduinars. Sometimes a developing growth fails to split into individual sceaduinars, creating a conjoined monster called a splinter twin. Splinter twins are larger and stronger than their regular kin.

Sceaduinars are immortal and live forever unless slain. Their negative energy souls make them almost impossible to resurrect.

Powers & Abilities
Sceaduinars wield the killing power of negative energy. They can manifest it as a variety of offensive magical effects. Additionally, their very flesh is essentially solid negative energy, which is harmful to the touch for living creatures. This also allows to strike intangible creatures and objects.

Sceaduinars also have other magical abilities. They can teleport themselves, dispel magical effects, and create zones of darkness. Curiously, it is very difficult for undead to observe sceaduinars.

Homeworld
Sceaduinars hail from the Negative Energy Plane, a dimension of pure entropy, and are one of the few creatures truly native to the plane. The Negative Energy Plane is a lightless void roughly the size of the material universe, bounded by massive cliffs that slowly fragment into the void. The entropic void is actively hostile to life and matter, rapidly killing living creatures and breaking down all but the largest objects in a matter of days. Only the entropic crystals and the creatures they spawn are immune to this effect, as are undead. Before they are broken down and replaced, cliff fragments glow a faint silver and resemble stars from a distance - these are the only natural light sources anywhere on the plane.

Sceaduinars usually live on the crystal formations that spawn them, but sometimes they settle on other solid objects or spend long stretches of time flying through the emptiness. While adapted to the Negative Energy Plane, they can survive elsewhere with little trouble, though they generally do not like it. When away from home, they prefer to spend time in deep space, the closest Material Plane environment to their native realm.

Society & Culture
Sceaduinars are driven to see entropy triumph over the cosmos and wipe out all other life. They harbor a deep cultural resentment over their inability to create and the dominance of positive energy life, which they blame on the jyoti - their positive energy counterparts - and the gods. They hate living creatures and undead alike, viewing the latter as parasites of negative energy. They do not care about outsiders of the Outer Planes as much, but still dislike them. The sceaduinar never worship gods of any kind, though some worship the Negative Energy Plane itself.

Sceaduinar settle in vast cities grown out of negative energy crystal formations. Since they cannot truly create, they must borrow architectural styles from other races, which further stokes their resentment and hate. They also gather in huge flocks away from any structure. Both kinds of gatherings are ruled by old and powerful sceaduinars. Sceaduinars also tend to spend large stretches of time alone.

Following the Gap, sceaduinars became less overtly murderous and more likely to make alliances, though they still retained their apocalyptic goals. Most notably, they have become the religious patrons of the draelik race, whose racial faith venerates entropy and the gradual ending of all things. The draeliks do not truly worship the sceaduinars, but they do venerate them as ideal forms of life and embodiments of entropy.