Luxic Biology
All people on Luxos share the same biological foundations, regardless of race or variant; they are humanoid and bipedal. Few Luxic people possess the physiological features needed to fly or breathe underwater without the use of magic. The molecular structure of a Luxic person is entwined with light, the flowing energy within everything on Luxos. As long as light is present, Luxic people can endure a great number of both physical and magical attacks without lasting effects.
Races and Variants
The races of Luxic people are denoted by specific physical characteristics determined by genetics. Besides these characteristics, the different races do not have any inherent biological/magical advantages or disadvantages. Children from a mixed race couple are classified under a "variant" derived from one of the parent races - for example, a drascus and alcerian couple may bear a drascus child without wings, known as an "apterous drascus." This terminology is mainly used in medical contexts or in official documentation, and has little bearing outside of such contexts.
Lumien
Lumiens have no extra appendages compared to other races. Their ears are relatively short (compared to an alcerian's), and may be rounded or pointed and upturned. Additionally, lumiens may or may not also have a pair of fanged teeth. Both pointed ears and fangs are more likely to be present in individuals with alcerian or drascus lineage, but are not necessarily traits indicative of a separate variant altogether.
Alcerian
Alcerians are most clearly characterized by a pair of smooth horns protruding from the front of the head. They may grow in any size or direction, but will only sprout from the forehead. Alcerians also have a thin tail that may or may not end in a point, which may or may not have hair or fur along the surface. The exterior of both an alcerian's horns and tail is a hardened skin tissue akin to cartilage. Like other body parts supported by cartilage, they have nerves that can register touch and pain, and will bleed/bruise upon injury. A severed horn or tail will never regrow.
There are two variants of alcerians - true and amalgam. True alcerians are of a lineage purely made up of lumien or other alcerians. Their horns and tail are the same color and texture as their skin. Amalgam alcerians possess drascus or munkin ancestry, resulting in horns and tail that are different in color to their skin. In addition, these appendages feel slightly tougher and more reinforced than regular skin.
Drascus
Like alcerians, drasci possess a pair of horns - however, they only protrude from the top, sides or back of head (and never from the front/forehead) and are composed of hard bone tissue, similar to teeth. A drascus' horns may or may not be ribbed (like a drill) or scaled (like a pinecone). Drasci may also have a tail, though thicker than an alcerian's and may be covered in fur or scales, and may have fins, spines or other appendages. The presence of both bone tissue horns and a thick tail are the key traits of a drascus. Drasci will always have at least one pair of fanged teeth (though typically have more).
Drasci present in one of two variants - alate and apterous. Alate drasci, usually from a lineage of winged munkin or other alate drasci, possess wings. These wings may be any size, and may either be membranous, webbed or feathered. Conversely, apterous drasci do not have visible wings, but may have some other organ or appendage, such as gills. This unusual genetic mutation occurred as an adaptation to the environment, and are typically associated with a certain region.
Munkin
Munkin are humanoids that possess traits similar to other lifeforms on Luxos. These features present themselves as modified ears or tail(s), but may also include extra appendages (such as wings). Munkin do not have horns, even if the lifeform they resemble does. There are no variant classifications of munkin.