The Killik species used a very complex language to communicate, far more sophisticated than Basic or Shyriiwook. The insects raised and lowered their abdomen, rapidly shut their mandibles and rubbed antennae together to convey their language. This language was incomprehensible to C-3PO when the Millennium Falcon first encountered the Killiks, and only the Jedi were able to communicate fluently with the alien species.
- The Old Republic
- Dark Nest I: The Joiner King (First appearance)
- Dark Nest II: The Unseen Queen
- Dark Nest III: The Swarm War
- Fate of the Jedi: Apocalypse