Sprocket is a compact rock gnome with copper-brown hair tied into a short topknot and a neatly braided beard threaded with tiny brass rings. He wears reinforced scale mail beneath a soot-darkened leather apron, with a shield marked by a painted spiral gear. His most noticeable habit is the constant adjustment of a small brass monocle-like lens mounted on his forehead. Within moments of meeting someone, his eyes have usually traveled from their face to their hands, belt, boots, and any mechanical object nearby, cataloguing how everything works and how easily it might fail.

Sprocket is observant, patient, and disarmingly earnest. He treats nearly every conversation as a collaborative investigation, asking precise questions and listening closely to the answers. He is courteous toward people who admit ignorance and quietly suspicious of anyone who pretends to understand something they have not examined. Although he prefers careful planning, he has a practical streak that sends him into danger when an experiment, mechanism, or missing person cannot wait.

Sprocket was raised in a rock gnome burrow built around an abandoned dwarven pumping station. While other children took apart clocks to see what made them tick, Sprocket listened to the pipes, measured the pressure changes, and drew diagrams of the hidden waterworks in the margins of every family ledger. His fascination eventually carried him into the study of magical engineering, where he learned to coax useful effects from simple mechanisms, careful mathematics, and a startling amount of patience. As a Sage, Sprocket spent several years copying damaged technical manuscripts for a remote academy. He became known for restoring unreadable diagrams and identifying the practical purpose of texts that other scholars dismissed as obsolete. His research ended abruptly when a senior colleague vanished after discovering references to a self-correcting arcane engine. Sprocket now travels with the colleague's final letter, seeking the missing engine and the truth behind the disappearance. He is not certain whether the device is a miracle, a weapon, or merely an elaborate mistake, but he considers finding out an obligation to both scholarship and common sense.