Vaikan were generally small and scrawny with large, long ears and large eyes. They had a short, nearly flat snout, and rows of short, sharp teeth in their mouth. Vaikan had four fingers including an opposable thumb as well as three toes. From their fingers, they could discharge jolts of electricity.
Having to adapt to the heavy radiation from their star, they evolved to have skin that varied in shades of blue. Not only could they survive this radiation, but they also metabolized it using special cells in their skin. Their large ears primarily fulfilled this function. Their ability to photosynthesize reduced their overall caloric needs which allowed them to adapt to their original desert environment.
Vaikan also had supplementary fins that could retract and extend. These fins also served as means of gathering solar energy. Overtime, these fins shrunk during their long time spent in spacefaring environments.
Vaikan had binocular eyes that allowed for depth perception and stereoscopic vision; eye color often varied between blue, purple, orange and red. Both eyes were large and oval-shaped, being taller than they were wide. They had two sets of eyelids - the outer ones blinked horizontally and the inner ones blinked vertically. Although they lacked trichromatic vision, they could see deeply into the ultraviolet spectrum. As such, they perceived their surroundings in shades of blue and purple with amounts of vibrancy and brightness denoting subtle color transitions.
Vaikan, as well as other species native to Ucharpli, had a unique brain chemistry with their own set of hormones. Because of this different chemistry, adrenaline from an outside source could induce powerful hallucinatory effects. For much of Vaikan history, adrenaline was considered an illicit drug.
Vaikan also required a four week hibernation period once every two standard years. During this time, they would enter a deep state of sleep and experience lucid, vivid dreams. In some cultures, it was common practice to write down the events of these dreams often to interpret for self-reflection or as prophecies for the next two standard years to come.
Vaikan have the ability to discharge electricity from their fingertips. Running down from their brain to their arms was a series of electrical cells. Upon activation via a brain signal, a reversal of charges occurred in the air. This shock could send enough volts upon the target to stun them for a few moments. An organ dedicated to holding electrical charges existed near their two hearts and sternum which could be charged through a combination of both caloric intake and periods of sleep.
The stun mechanism was an evolutionary leftover from their more primitive ancestors who used electric shocks to ward off their enemies. When Vaikan evolved to become predatory creatures, they learned how to use their electrical abilities in conjunction with weapons such as copper spears.
Vaikan metabolized most often from their ability to absorb UV radiation. However, in order to survive cave environments as well as Ucharpli's lengthy periods of nighttime, they needed to directly be able to ingest food as well. Thus, their teeth were designed to be able to extract liquids from their meals, but they were capable of swallowing solid food as well. As they lacked a direct equivalent to a stomach, their esophagus connected straight to their small intestine which then processed the food throughout the rest of the digestive system. The small intestine was particularly elastic and could expand, unravel or otherwise rearrange itself to hold extra food if it became necessary. This would most often occur during the winter when Vaikan would ingest more food than usual to prepare for their four week hibernation period.
Once enough nutrients had been extracted, uric acid was excreted through their cloaca as a means of conserving water and removing toxins from the body.
Vaikan naturally lived to approximately 160 standard years. Although Vaikan possessed object permanence upon hatching, they had an otherwise fairly slow aging process when it came to cognitive development. They did not gain the ability to self-recognize until age ten standard years. Males and females looked nearly identical until puberty. The main reliable way to tell young Vaikan apart from one another was their size. Males would on average grow much taller and develop much larger ears and solar fins.
After approximately age 20, their sexual dimorphism would become much more prominent. The development process would last approximately ten standard years, during which time, their hormonal growth would accelerate. The development process would last until approximately age thirty. As such, across many Vaikan societies, age of consent ranged from age 25 and 30.
Upon sexual maturity, their brains became fully developed, and they gained better control over their emotions and become more adept at solving mathematical and logical problems.
Vaikan were monotremes - both males and females used their cloaca for reproduction. After conception, a soft-shelled egg would develop inside the female and would be laid after seven months. Hatching would take approximately one month, and the hatchling would break open the egg from the inside via an egg tooth. The mother would then nurse the hatchling with milk.