Dark Elf

Dark elves... As beautiful as they are deadly. Throughout their history they have followed some of the most evil individuals in history, from Morthos the ancient demon-lord known as the Silver Tongued Demon, to Althos, first in his capacity as an evil god of darkness, poison, and magic, and then in his capacity as a demon lord of darkness, hunger, and the void. Some of Althos' most distinct servants and fanatical cultists are dark elves. He appeals to their innate wickedness and extremism. Truly a combination made in the deepest pits of the Heart of Darkness.

-A high elf historian, commenting on the link between Althos and dark elves.

Dark elves are a powerful subspecies of elves that are commonly found in evil dimensions and in worlds beneath worlds. They are innately a darker race, with regards to cultural attitudes and practices and are fond of something akin to demon worship as well as magics that involve demons. 
Along with ogres and undead beings, dark elves were some of the first evil worshipers of Althos and in the world of Torus, many of them swiftly became passionate althonites. 
Author's Note: This is a living article, and as such over time it will be updated for both the sake of clarity and to reflect new information shared in the story. 

Trivia:

• Dark elves are thus far the only example of a humanoid race having at least one known race they can transcend into, with dark elves being known to very rarely transcend into driders a race that could be described as half-drow and half-giant-spider. Despite this, it is known that all humanoid races can transcend into various other races.
• The first demon lord to be named in the story was mentioned in reference to dark elves, Morthos, also known as the Silver Tongued Demon. Morthos is himself a reference to a character the author played in a long D&D campaign with the same name, who was a bard, a tiefling, a non-violent quasi-pacifist, and had a nemesis who was a dark elf.
• The first family in the story to serve as a sort of mini-set of recurring antagonists were a dark elven family, the Ardors, who since being dealt with have become some of the strongest necromancers and in some cases undead beings in the story.
• The first naturally occurring portal in the story was discovered in the dark elven city of Aronms, beneath the Morothian Mansion. 
• Dark elves and humans are the two races thus far with characters that are explicitly stated to be hybrids. Lilith Silverstone is a half-demon, and Isadora Santiago is a half-angel. 

Basic Information

Anatomy

True dark elves, as in those who aren't hybrids with one demonic parent and one dark elf parent, have the same basic anatomical structure as humans which is the norm for humanoid species. They have two lithe but powerful arms, two skinny but deceptively well-muscled legs, and their bodies are, on purely physical levels anyway, superior to those of high elves. Dark elves are well known for being incredibly attractive, and for being as cruel as they are pretty or handsome. 
Dark elves have skin and muscles harder than iron and are quite difficult to injure. The unusualness of their skin and muscle density strongly suggests that somewhere, early in their existence as a distinct subspecies of elf, a deity of at least intermediate-level strength took in an interest in them and blessed them so powerfully that their species retained the blessing since then. 
Half demon dark elves possess anatomies that are dependent, in part, on what kind of parent their demonic parent is.

Genetics and Reproduction

Dark elves, like all elves but forest elves, undergo much longer pregnancies than humans do. Their pregnancies last fifteen months, and are difficult on their bodies unless they are half-demon children of succubi, or blessed by a deity such as Althos. They reproduce through sex, and agnostic and atheistic dark elves are far less likely to reproduce successfully than Althonite and Althonian dark elves, which demonstrates the favor felt by dark elves who devote themselves to Althos.
Althos is a deity of fertility in many people's and civilizations' eyes and so this makes some level of sense.

Growth Rate & Stages

Dark elves are considered infants for the first four years of their lives and what passes for their childhoods and adolescences takes roughly sixty years, though physically they reach adulthood as early as their mid-twenties. Dark elves, even unblessed, can live up to two thousand years before dying of natural causes, though blessed dark elves can live up to sixty thousand years before perishing of natural causes. This is speculated to be because of a lingering component of their distant fey ancestry, and it is known that many dark elves have extremely powerful vestigial traits, which can be seen in the rare few who've managed to unlock and reawaken their vestigial traits.

Ecology and Habitats

Dark elves favor life underground. Their anatomies are uniquely suited to be able to do well underground, despite the fragility of their appearances. They like lightless environments where their ability to see regardless of light levels provided there's even a single shred of light somewhere grants them an advantage over their enemies and victims. 
Dark elves, and their slaves or servants, are capable of tremendously influencing their environment on a scale often unthinkable to races such as humans. Dark elves are capable of exhaustion, but the most skilled or blessed groups of them have servants that are not. Althonian dark elves are extremely fond of necromancy but a particularly blessed dark elven family or even an individual may be lucky enough to have elemental servants and a dark elf with an element servant or two is capable of rapidly shifting the environment of wherever they settle.

Dietary Needs and Habits

Dark elves are natural omnivores and have traits routinely found in them such as the distinctive teeth of such creatures. Dark elves or their servants, or slaves in non-Althonian settlements, grow fungi for food, but they also practice both cannibalism and the consumption of different types of humanoids.

Biological Cycle

Dark elves are a powerful, ancient race, and like many powerful, ancient races they grow more powerful as they age. This trait makes ancient dark elves extremely dangerous creatures, though cities like Aronms, where Althos first encountered dark elves, are run by fairly young members of their race. 
As dark elves age their skin begins to harden and the oldest unblessed dark elves need assistance with moving but are incredibly wise creatures and in many cases can spread their unusual petrification to others with a touch. That said one way around that is to be impregnated by a demon, and another is to receive the blessing of a god. Both are powerful ways around an annoying condition. 
Curiously the odd condition that occurs to the oldest non-blessed dark elves strongly suggests that they were either loved or hated by an incredibly powerful elemental overlord and if it's the latter then it is not clear why they feel so comfortable dwelling underground.

Additional Information

Social Structure

Dark elves are extremely social and their cities can be massive, housing tens or even hundreds of thousands of them. There is a persistent myth about dark elves that suggests that their societies are inherently matriarchal, but that is not necessarily true. This myth's origin is due to the popularity of the worship of Morthos, the Silver Tongued Demon, among dark elves. 
Morthos hatred dark elves and one way he took out his rage on them that was by rearranging dark elven societies so that the cruelest dark elven priestesses rose to the top of dark elven society and encouraged cruelty among their lessers to make life as bad as possible. He was also responsible for the strange habit of mating with demons that many dark elves, both male and female, continue to practice to this day. Morthos was able to achieve this due to his unbelievable charisma and his burning hatred for dark elves, which was such a powerful combination that its effects still color dark elven society, over half a million years after Morthos' death. 
The truth is that barring demonic influence dark elven society is surprisingly egalitarian. Numerous dark elven cities are led by male dark elves and most dark elven cities in the Althonite empire are actually led by pretty evenly representative councils of dark elves, who are often historians or other sorts of sages.

Facial characteristics

Dark elves have eye colors that are impossible for humans, such as jet black, purple, scarlet, electric yellow, and pink.

Geographic Origin and Distribution

Dark elves gravitate towards subterranean places and can be found, theoretically, in any world with elves and an abundance of underground ecosystems for them to inhabit. They are also, very rarely, capable of not being evil, but those dark elves are likely to be hunted by other dark elves, in some cases purposefully at the commands of creatures like Althos or sufficiently powerful and influential demons, and so in the rare cases where a dark elf isn't evil they may just flee to the surface and seek refuge among surface-dwelling races. Another instance that may cause dark elves to go to the surface of their homeworlds might be a divine command or worse yet, exile. 
That said there are a handful of worlds, both in and out of the Althonite Empire, where dark elves have taken control of the surface of the world. Typically that is because of post-apocalyptic conditions on the surface that benefit the dark elf, such as in one actual case a devastating and purposeful redirection of solar energy that caused much of the world's surface to begin to die until that world's dark elven population revealed themselves and demanded control of the world in exchange for giving surface dwellers a chance to survive. Those dark elves were althonites, and the world gave into them. That planet's supreme leader is a level 20 cleric of Althos' and has both demonic and devilish servants.

Average Intelligence

Dark elves are naturally extremely intelligent, having retained the ancient blessings that gave primordial elves their intelligence while evolving a propensity towards cruelty and creativity in maliciousness.

Perception and Sensory Capabilities

Dark elves have extremely delicate senses and are capable of manifesting extrasensory perceptions. One example of that latter trait is the Ardor family having a few members capable of telepathic communication. Dark elves, especially half-demon dark elves, are also commonly capable of infrared vision, which is extraordinarily useful in the most common habitat that they can be found: subterranean environments. 
Dark elves also possess the full suite of senses available to most other humanoid races, touch, hearing, smell, taste, and sight.

Genetic Ancestor(s)

• High Elf

Origin/Ancestry

Corrupted offshoot of high elves, the first and oldest elf species

Lifespan

2,000 years old

Average Height

Unblessed dark elves tend to be somewhere in the 1.8 meter to the 2.1 meter height range.
Blessed dark elves are much taller, standing between 2.7 meters tall to 3.2 meters tall.

Average Physique

Dark elves are surprisingly strong but more than that have an astounding natural dexterity. That dexterity is what allows them to be successful in fighting enemies off underground and also use an array of weapons skillfully.

Body Tint, Colouring and Marking

Dark elves tend to have darker colorations and their skin tends to be various shades of purple, black, or even gray.