The Iron Worm was a gargantuan worm-like anaxim with an articulated metallic body that stretched over a hundred feet (300 meters) in length. Its metallic scales were mostly rusted and worn out but were several feet thick and constantly sparked with small lightning discharges. Although the Iron Worm didn't seemed to possess eyes, ears, a mouth, or any other method to interact with and sense the world, it moved with uncanny precision both in the surface or burrowing underground.
It was believed that the Iron Worm possessed the ability to communicate psychically with those it deemed worthy, although such individuals were very rare. The Iron Worm was usually innocuous, but it crushed any creature that attempted to block its movement or that attacked it, even other anaxims.