
In Frank Herbert's Dune, sandworms are colossal, territorial, and extremely aggressive creatures. They are attracted by rhythmic sounds and have the ability to burrow in and out of sand. They are nearly indestructible.
Within the novels, sandworms are responsible for the creation of spice mélange as its sole source. Spice mélange is the most valuable commodity in the universe as it is the only feasible way to make interstellar travel possible. Harvesting spice is extremely dangerous due to the presence of these sandworms.