Kett biology is a driving force in their expansion. The kett are capable of transferring beneficial genetic traits from other species during exaltation, modifying their genome and expressing new traits almost immediately.
Study of kett DNA shows evidence of horizontal gene transfer and the incorporation of genes from dozens of unknown species. Their cells have transfective properties normally only seen in specially engineered laboratory animals, meaning the kett are able to "custom-mutate" their genome.
All kett and their exalted have a distinctive white exoskeleton. Dissection reveals these growths contain fluid-filled sacs that capture dissolved gasses from the circulatory system, slowly releasing them if the kett is oxygen-deprived. The fluid pressure of these sacs also stabilizes the body if environmental pressure is reduced. This helps the kett survive hazardous planets or even in the vacuum of space without suits, while providing additional protection against gunshot injuries.