A flat wall, not the child, is the real sculptor here. From a single courtyard lamp, light rays spread in straight lines, so any body placed between lamp and wall becomes a crude projector that throws a magnified contour into view.
The strange part is scale, not shape. Because of basic projection geometry, when the child stands closer to the lamp than to the wall, small shifts in posture produce large changes in the outline where the light is blocked. Arms lifted and slightly bent form two sharp occluding edges; on the wall, those edges stretch upward into exaggerated “horns”, a textbook example of umbra expansion with distance from the light source.
The monster quality is finished by the observer, not the physics. Viewed at a shallow angle, the elongated shadow suffers foreshortening, while low illuminance outside the beam leaves the background in near-darkness. In that sparse field of cues, the brain’s shape-from-silhouette process and pareidolia happily upgrade a child’s ordinary stance, plus one courtyard lamp, into something towering and horned.
