The Killik were a sapient insectoid species native to Alderaan. They built large mound-like structures on the plains of both Alderaan and Alsakan. Long before most other species came to these worlds, the Alderaanians vanished. Their disappearance from Alderaan was depicted in Ob Khaddor's moss painting Killik Twilight.
Their societies were structured as huge nests, with individual Killiks differing wildly from each other in shape and size, some being as huge as a starship, others as small as a mite. All nest members were united by a telepathic hive mind, which could be extended to non-Killiks as well: those non-Killiks who became part of their societies were known as Joiners.