The Walker is a giant, skeleton-like creature with blue flames surrounding its face.
The Walker appears at the end of the normal mission's path of Cryptic Castle in Shadow the Hedgehog. It is immune to damage and cannot be killed. It chases Shadow down a set of three grind rails. In order to escape from it, Shadow must perform 180s or use the Dash Rings to stay ahead of the monster. The first Dash Ring is located on the left rail and the second is on the right rail. However, if the Walker catches up to and touches Shadow, he falls off the rails and the player will lose a life.
- The Walker appears to be of mysterious origin, as neither Eggman nor Amy seem to know what it is or why it's there.