One of the swiftest land animals on Tatooine, the rill is a reptilian predator that hunts womp rats and other large mammals. Fiercely territorial, an individual rill (or a rill and its young) stakes out a patch of desert and defends it vigorously against all intruders. To sleep and protect itself from Tatooine's blistering heat, the rill burrows into the sand several meters below the surface.
These nests are also where rills lay their eggs, burying the eggs under sand to hide them from scavengers. The first task of a newly hatched rill is to successfully dig its way back up to the surface, or else be abandoned by its mother and broodmates.