Viska The Viska ( singular , Visk ) were winged sentients , indigenous to Rordak . Biology and appearance . The Viska ' s bodies were between two and three meters long , while their leathery wings spanned five meters . They had a pair of arms in the center of their body used for manipulation . They had long , narrow heads , with wide - set eyes and large ears . Their eyes were so widely placed that they could see all the way around themselves , even directly behind them . They also possessed infra - red vision , allowing them to see perfectly in the dark . Most prominently , they had a forty - centimeter long needle - sharp proboscis . Their circular mouth extended this proboscis - called a blossug - when feeding . It was made of several layers of strong muscles covering a hollow bone with a sharp jagged tip . This bone would be pushed into the flesh of their victim , whereupon the Visk would use muscles in their snout and skull to drain the creature ' s blood . Due to their primitive digestive tract , they were completely unable to eat meats or plants . They had to consume two liters of blood per day . Creatures from their homeworld - mostly grazing herd animals - provided the most nutrition to a Visk . They would refrain from feeding on alien creatures or sentients , as off - world blood would often physically harm them . Viska would not feed off of one another , but could use their blossug as a weapon in physical combat . Viska expended a great deal of energy in their day - to - day activities , and had to rest for at least eight hours a day . Society and culture . Their world was ruled by a caleisk , a monarch who was chosen when their predecessor died . All of the caleisk ' s children would battle to the death , with the sole survivor becoming the new monarch . This new ruler would then choose between three to six clans who would control all of the repulsorlift cities across the planet . These chosen clans were called the lurinn , whereas unempowered clans were called calsedra . Each clan was ruled by a calsk . When the calsk died , his children would also fight to the death for power , just like those of the caleisk . Power would only shift to a new family if a calsk died without any children . Each family would then choose a leader , who would battle all other chosen leaders for the calsk position . Each lurinn clan had absolute authority over particular calsedra clans , and each calsk likewise had total authority over each Visk in his clan . Individual Visk were told what tasks or occupations they could have , and had no choice in the matter . They would often excel in their professions , but as Viska society was highly merit - based , they would mostly try to move upward in society through success . Viska were always seeking more wealth , influence , and comfort , as well as a higher personal status and a higher status for their clan . In order to prevent any back - handed or stealthy methods of altering Viska power - structure , such as assassination - rather than the all - out battles that decided their leaders - any individual found guilty of participating in such a plan would be executed , if the victim was within their family . If the victim was a member of another family , the guilty party ' s entire family would be executed . The Viska lived in large repulsorlift cities . This was due to the volatile nature of Rordak ' s surface , which suffered from groundquakes and volcanic eruptions . Even before Republic scouts brought repulsorlift technology , the Viska had developed a society that stayed away from the ground . With their new technology , the Viska developed a completely aerial society . These cities were huge structures , made completely open to the air due to the Viska ' s large wingspans . Their buildings were attached to enormous repulsor columns , over 500 meters long and 100 meters in diameter . The levels of these cities would often extend thousands of meters into the air . The upper levels of their cities were reserved for the royals of the clans , while the lower workers and clans lived on the bottom levels . The middle levels were used for manufacturing , trading , and as spaceports . Due to their need for large quantities of blood , the Viska tended to enormous herds of grazing animals , such as the kessarch and the drivveb . They imported vast amounts of grain and grasses to feed these herds . It was rare for a Visk to leave Rordak . If one did , they were forced to avoid elite Viska warriors and bounty hunters their clan would send after them . Due to their diet of blood , and their well - known disregard for the sanctity of life , they were commonly referred to by off - worlders as " the great bloodsucking fiends of Rordak " . This was erroneous , however , as they very rarely fed off of other sentients . Even still , they were very intimidating to off - worlders , a trait the Viska were very proud of . History . The Viska had progressed to an atomic level of technology on their own before being contacted by other sentients . When Republic scouts arrived , the Viska eagerly embraced their space - level technology . The " bloodsucking fiends " soon became well - known throughout their home sector . By the rise of the Galactic Empire , the Viska had been part of galactic society for over three centuries . After the formation of the Empire , the Imperials immediately began to use the planet as a prison world . Behind the scenes . In " " , Viska is mistakenly used to refer to only one of the species .