A qworlth skaal, sometimes called a dread weapon, existed as a bio-engineered, worm-shaped entity projecting outward from the front of a Yuuzhan Vong warship or worldship. This creature had the capacity to bore into the outer layers of an opposing ship or space station, draining all life forms within. As another option, this dread weapon possessed the ability to pierce the crust of a planet, which was demonstrated on Helska IV during the landing of the first Yuuzhan Vong worldship.