A lean, pale man with tousled silver hair that falls into his eyes and a long, sharp-boned face. He favors an open, sleeveless coat over a bare chest, as if winter were an inconvenience rather than a danger. His hands are broad, dry, and roughened by years of handling ice-cut stone; the pads of his fingers are permanently ridged, like old-fashioned printer's type. He moves with loose, economical balance, never quite standing still. He smells unmistakably of pine pitch and cold ashes, a scent that clings to his clothes even after he has bathed. His unexpected detail is a tiny, meticulous collection of pressed flowers tucked into a waxed notebook.

Muro is generous with labor and stingy with reassurance. He jokes when a room is tense, yet becomes painfully direct when someone is in danger. He loves the ordinary comforts of a warm kitchen but will sleep in a snow trench rather than ask a stranger for shelter. He is proud of his skill and distrustful of anyone who calls it a gift.

Muro was born among the quarry families of a northern valley, where his mother taught him to read weather in the color of snow and his father taught him to cut stone without wasting a strike. As a young apprentice, he found a sealed chamber beneath the quarry, its walls covered in frost that did not melt. He broke the seal during a desperate attempt to shelter miners from a blizzard. The magic inside saved their lives but permanently changed his hair and awakened his gift for wizardry. Years later, a spell of his own design collapsed a glacier onto a raiding army, but the flood it caused destroyed the village of Sovo downstream. Muro has spent two decades rebuilding its homes and refusing to let its survivors call him a hero. He remains close to his former student, Peli, who now argues that the valley needs his power more than his penance. He is currently trying to stop a mining company from reopening the chamber that first changed him.