Chuk'a
this large, mollusk-like worm was bio-engineered by the Yuuzhan Vong as a waste processor. It dug through all sorts of materials, including metal and stone, with a hard, shell-like cap that contained several pincers. The chuk'a then move through rock and other material, grinding up anything it encountered and consuming it. The chuk'a then digested the material and exuded a recycled form of matter that could be used to construct buildings and structures. The looping tunnels formed as the chuk'a passed were then used to connect underground chambers. When the chuk'a was not needed, it was commanded to simply go to sleep. This sleep was very deep, and required a complex set of stimulations to rouse the chuk'a again. It was considered very dangerous to awaken a sleeping chuk'a. A number of these creatures were set loose on Coruscant, after the Yuuzhan Vong began to transform the city-world into a simulacrum of their long-lost homeworld of Yuuzhan'tar, to help destroy the deepest layers of construction below the planet's surface.